July 2010 Oregon Beach Ultralight DXpedition Report


Gary DeBock
 

Hello All,
 
For those interested in the rather new sport of Ultralight Radio Dxpeditions, a detailed file describing the results of a recent 7-day trip to Seaside and Lincoln City, Oregon has been prepared.
 
With unusually good South Pacific propagation continuing for almost a week, the modified Tecsun PL-380 and 3' portable loop (with a total cost of $125) went into overdrive, logging many DU's that had never managed even a trace for John Bryant or me on ULR's at Grayland, WA. The DXpedition report includes photos of the overachieving equipment, and includes links to 27 MP3's recorded at the beach (including some South Pacific stations that are fairly obscure). It has been uploaded to the ULR feature article section on DXer.Ca at http://www.dxer.ca/file-area/cat_view/87-ultra-light-radio-files-area/99-ulr-feature-articles , to the Yahoo Ultralightdx File Section under Members' DXpedition reports at
 
 
and has also been uploaded to http://www.mediafire.com/?we4r6gh50gaa4i6 .
 
 
Sincere thanks are in order for Patrick Martin, Chuck Hutton, Bruce Portzer, Guy Atkins and Walt Salmaniw, all of whom provided useful station information to help make the DXpedition successful. Thanks a bunch, guys!
 
73 and Good DX,
Gary DeBock (in Puyallup, WA)
 
      
 
 


Gary DeBock
 

Hi Richard,
 
Thanks for your kind comments on the DXpedition report, and yes, it's always far more fun to receive lots of transoceanic DX on a radio and loop that only cost about $125! Selectivity advancements in the new DSP receivers (like the PL-380) have made this bargain DXing concept possible, and once a few other DXers try chasing TA's or TP's this way, I think the idea will catch on like wildfire.
 
Here on the west coast we can't do too much about the early hour sunrise enhancement period to chase DU's, unfortunately. The worst of the sunrise time slots here is around June 21st (the earliest possible), where the DU's start fading in around 0445 local time. John Bryant and I had a joint Grayland DXpedition on July 9th last year (pretty close to the earliest sunrise), when we both got up around 0230 local time to set up everything :-)  East Coast DXers have all the luck, it seems, with convenient sunset TA fade-ins...
 
73, Gary    
 
 In a message dated 8/3/2010 3:06:57 P.M. Pacific Daylight Time, farmerik@... writes:

 

Thanks for that excellent report! You certainly did very well without spending a lot of money on the radio and antenna. It is more fun that way for me as well.

One thing I noticed is your VERY early listening time. I don't think I would get up well before dawn on my vacation.

I am planning to try for TA logging this Fall while vacationing on the coast of Maine. I hope the evening is a good time for listening. -FARMERIK

--- In ultralightdx@..., D1028Gary@... wrote:
>
> Hello All,
>
> For those interested in the rather new sport of Ultralight Radio
> Dxpeditions, a detailed file describing the results of a recent 7-day trip to
> Seaside and Lincoln City, Oregon has been prepared.
>
> With unusually good South Pacific propagation continuing for almost a
> week, the modified Tecsun PL-380 and 3' portable loop (with a total cost of
> $125) went into overdrive, logging many DU's that had never managed even a
> trace for John Bryant or me on ULR's at Grayland, WA. The DXpedition report
> includes photos of the overachieving equipment, and includes links to 27
> MP3's recorded at the beach (including some South Pacific stations that are
> fairly obscure). It has been uploaded to the ULR feature article section on
> DXer.Ca at
> _http://www.dxer.ca/file-area/cat_view/87-ultra-light-radio-files-area/99-ulr-feature-articles_
> (http://www.dxer.ca/file-area/cat_view/87-ultra-light-radio-files-area/99-ulr-feature-articles) , to the Yahoo
> Ultralightdx File Section under Members' DXpedition reports at
>
> _http://f1.grp.yahoofs.com/v1/MIZXTHnyBjpUSAhtecD4IPeopYbvPYtKsBYdo1ZALlUnLj
> DgZnT_zlQ2Md_ZmT-E8NNwUUITlwF9EJiGadRr7rCoHeN9qTc/Members%20Loggings%20%26%2
> 0DXpeditions/July%202010%20Oregon%20Beach%20Ultralight%20DXpedition.doc_
> (http://f1.grp.yahoofs.com/v1/MIZXTHnyBjpUSAhtecD4IPeopYbvPYtKsBYdo1ZALlUnLjDgZ
> nT_zlQ2Md_ZmT-E8NNwUUITlwF9EJiGadRr7rCoHeN9qTc/Members%20Loggings%20&%20DXpe
> ditions/July%202010%20Oregon%20Beach%20Ultralight%20DXpedition.doc) ,
>
> and has also been uploaded to _http://www.mediafire.com/?we4r6gh50gaa4i6_
> (http://www.mediafire.com/?we4r6gh50gaa4i6) .
>
>
> Sincere thanks are in order for Patrick Martin, Chuck Hutton, Bruce
> Portzer, Guy Atkins and Walt Salmaniw, all of whom provided useful station
> information to help make the DXpedition successful. Thanks a bunch, guys!
>
> 73 and Good DX,
> Gary DeBock (in Puyallup, WA)
>


Gary DeBock
 

Thanks Tony,
 
Your comment is appreciated, and I sure wish you could have been with me in Oregon to help sort out the Kiwi station mysteries :-)
 
603-Waatea was a solid regular every morning, along with 675-National Radio and 657-Southern Star. 648-Rhema kept me well inspired. The entire DXpedition was a total blast for the humble setup I was using, but I hope your results in the summer will be even better!
 
73, Gary
 
 In a message dated 8/3/2010 4:07:15 P.M. Pacific Daylight Time, tonyzl@... writes:

 

Great reception bites of Waatea Rhema and National Radio stations – hope next summer I get the same of stateside stations. Regards,

Tony King

Greytown NZ


Rik
 

Thanks for that excellent report! You certainly did very well without spending a lot of money on the radio and antenna. It is more fun that way for me as well.

One thing I noticed is your VERY early listening time. I don't think I would get up well before dawn on my vacation.

I am planning to try for TA logging this Fall while vacationing on the coast of Maine. I hope the evening is a good time for listening. -FARMERIK

--- In ultralightdx@..., D1028Gary@... wrote:

Hello All,

For those interested in the rather new sport of Ultralight Radio
Dxpeditions, a detailed file describing the results of a recent 7-day trip to
Seaside and Lincoln City, Oregon has been prepared.

With unusually good South Pacific propagation continuing for almost a
week, the modified Tecsun PL-380 and 3' portable loop (with a total cost of
$125) went into overdrive, logging many DU's that had never managed even a
trace for John Bryant or me on ULR's at Grayland, WA. The DXpedition report
includes photos of the overachieving equipment, and includes links to 27
MP3's recorded at the beach (including some South Pacific stations that are
fairly obscure). It has been uploaded to the ULR feature article section on
DXer.Ca at
_http://www.dxer.ca/file-area/cat_view/87-ultra-light-radio-files-area/99-ulr-feature-articles_
(http://www.dxer.ca/file-area/cat_view/87-ultra-light-radio-files-area/99-ulr-feature-articles) , to the Yahoo
Ultralightdx File Section under Members' DXpedition reports at

_http://f1.grp.yahoofs.com/v1/MIZXTHnyBjpUSAhtecD4IPeopYbvPYtKsBYdo1ZALlUnLj
DgZnT_zlQ2Md_ZmT-E8NNwUUITlwF9EJiGadRr7rCoHeN9qTc/Members%20Loggings%20%26%2
0DXpeditions/July%202010%20Oregon%20Beach%20Ultralight%20DXpedition.doc_
(http://f1.grp.yahoofs.com/v1/MIZXTHnyBjpUSAhtecD4IPeopYbvPYtKsBYdo1ZALlUnLjDgZ
nT_zlQ2Md_ZmT-E8NNwUUITlwF9EJiGadRr7rCoHeN9qTc/Members%20Loggings%20&%20DXpe
ditions/July%202010%20Oregon%20Beach%20Ultralight%20DXpedition.doc) ,

and has also been uploaded to _http://www.mediafire.com/?we4r6gh50gaa4i6_
(http://www.mediafire.com/?we4r6gh50gaa4i6) .


Sincere thanks are in order for Patrick Martin, Chuck Hutton, Bruce
Portzer, Guy Atkins and Walt Salmaniw, all of whom provided useful station
information to help make the DXpedition successful. Thanks a bunch, guys!

73 and Good DX,
Gary DeBock (in Puyallup, WA)


Gary DeBock
 

Hi Richard,
 
Yes, I also wish you could have been in Oregon to enjoy the wild DXing fun-- chasing AM stations in Australia, New Zealand and the Pacific (from the west coast) is about the only way to have much AM-DXing fun in the middle of summer. It's kind of like a head start on the Fall Season!
 
The 7.5" loopstick PL-360 would have received all the South Pacific DX at the same signal levels as the 7.5" loopstick PL-380, but with more domestic splatter in some cases (because of the fixed 3 kHz DSP selectivity in the PL-360). This wouldn't have happened in all cases, though, like in receiving 891-5AN, which had no domestic splatter anywhere nearby. The 7.5" loopstick PL-360 should be a fun radio for domestic DXing, where the selectivity requirements aren't as great as in 9 kHz-split DXing.
 
73, Gary    
 
In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time, richarda@... writes:

 

Gary:

Thanks for the report. I wish I could have been there to enjoy the DXing fun. It would have been nice to see how the PL-360/7.5" combo might have performed.

Richard.

Richard Allen
36°22'51N / 97°26'35"W


Tony King <tonyzl@...>
 

Great reception bites of Waatea Rhema and National Radio stations – hope next summer I get the same of stateside stations. Regards,

 

Tony King

Greytown NZ


bbwrwy
 

Gary:

Thanks for the report. I wish I could have been there to enjoy the DXing fun. It would have been nice to see how the PL-360/7.5" combo might have performed.

Richard.

Richard Allen
36°22'51N / 97°26'35"W


pianoplayer88key
 

So are there any tips, short of going to an alternate location, to try for international DX with my PL-380 and Select-A-Tenna? I live in a fairly RF-saturated environment, which doesn't help, and it's difficult, if not impossible, for me to travel to other locations at this time. (If I had the opportunity, I might want to try going to somewhere west of Santa Barbara, CA (on the California coast) to try for some DX, but that doesn't look like it will happen anytime in the near future.) For now, though, the maximum extent of my "DXpedition trek" would extend to my back yard on the 1/2-acre lot.
And, for "international", for purposes of this post, I'm not including Mexico - I can get several AM and FM stations 24/7, some of which peg the SNR meter, and one AM pegs the RSSI meter in the daytime as well.

Or, should I resign myself to never doing any meaningful DX from here, and sell my PL-380? I do remember Scott Willingham in a post last week or so mentioning something about 3 ways to improve selectivity, one of which was to install passive filtering in front of the DSP chip. Is doing something like that that even remotely a possibility? And, while I'm at it (if I was to attempt something like that), what about pulling the guts out of the PL-380 cabinet, substituting a separate loopstick (would have to be no longer than 3 to 4 inches long and 1/2 inch thick, assuming it takes the entire width and almost the entire thickness of the radio, as it will have to fit in my pants pocket and 4" is the absolute maximum width that would reasonably go in there - my PL-380 will go in there but it's awkward), and basically crafting my own vertically-oriented ultralight based on the PL-380's guts, or would it not even be considered in the "unlimited" category? :(

--- In ultralightdx@..., D1028Gary@... wrote:

Hi Richard,

Yes, I also wish you could have been in Oregon to enjoy the wild DXing
fun-- chasing AM stations in Australia, New Zealand and the Pacific (from the
west coast) is about the only way to have much AM-DXing fun in the middle of
summer. It's kind of like a head start on the Fall Season!

The 7.5" loopstick PL-360 would have received all the South Pacific DX at
the same signal levels as the 7.5" loopstick PL-380, but with more domestic
splatter in some cases (because of the fixed 3 kHz DSP selectivity in the
PL-360). This wouldn't have happened in all cases, though, like in
receiving 891-5AN, which had no domestic splatter anywhere nearby. The 7.5"
loopstick PL-360 should be a fun radio for domestic DXing, where the selectivity
requirements aren't as great as in 9 kHz-split DXing.

73, Gary


In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time,
richarda@... writes:




Gary:

Thanks for the report. I wish I could have been there to enjoy the DXing
fun. It would have been nice to see how the PL-360/7.5" combo might have
performed.

Richard.

Richard Allen
36°22'51N / 97°26'35"W


Tony Germanotta
 

Stephen, you  keep asking the same question in different ways, but the answer can't change. If you are in an area where your portable radio is being overwhelmed by RF splatter from other stations, it's pretty much impossible to hear the, by definition, faint signals from DX stations. It's like trying to DX under the noise of a bad fluorescent bulb. I have one in a back room that just wipes out the entire band when I forget to turn it off. 

Can you build a preselector? Sure. What will it do. Well, there are types that peak up just one narrow band of frequencies. That helps sometimes, and others that block out either everything above its designed frequency or everything below. And those can help sometimes and some that just notch out one slice of the bandwidth. Again, it can help in some conditions. 

But if your area is buried by off-frequency splatter, which seems to be the case from your various postings, then none of those will help at all because the offending frequency will be on the same frequency you are trying to DX. If you filter it out, your DX is also blocked from the receiver. The FCC in recent years has become pretty lax on keeping AM stations to their specs, I have discovered. There just aren't that many folks like us out there who get offended by the local talk station bleeds over 10KHz, since there is usually no other local station on the air there. And the days of clear channel stations designed to cover wide sections of the country are over. Those frequencies are now shared by several stations with national coverage now something ceded to the internet, satellite radios or just not deemed a national priority anymore. 

You keep searching for more sensitivity when your problem is probably too much signal already. 

Changing out the internal ferrite won't help if it makes the radio more sensitive in an area already over washed by RF. What you might want to do is cut sensitivity some. That's easy on radio's with a DX/Local switch that puts an attenuator between the antenna and the front end. You can do that yourself on shortwave or FM with your radio, but the AM circuit doesn't have that kind of outside input unless you go to the little one with the external antenna jack. On that one, you could put a variable resistor, or Pot, in line and use that to cut signal. There are better ways to do it, with resistance boxes, if you find the rough method works. With your radio, the antenna is always in line. So you can try reducing signal by putting the radio in a grounded metal can, for instance, with just a small opening for RF to get through. That might reduce the RF to below the point where it is overwhelming the chip and causing it to do weird things by going what they call non-linear.  Before you do that, though, try to borrow a radio with an attenuator on board and see if it does anything for you. Again, if the locals are broadcasting over adjacent frequencies rather than your radio just being overwhelmed and reproducing them on those frequencies, attenuation won't help. It will just reduce both the DX and the local pest equally and the DX is going to be the loser, since it is much, much weaker. If the attenuation helps, then you know it's overload causing the majority of your problems. And you can build your attenuating can. 

Of course, you won't be able to fit that in your pants pocket. Then again, DXing isn't something you do while taking a walk. Moving a couple feet inside a house can make a ton of difference in DX sometimes because of the way the radio waves are being reflected and blocked by stuff in your walls an attic.  That said, sometimes heading to the far reaches of the back yard can improve things by getting away from near field RF noise. Then again, you may just be moving closer to the neighbor with the bad bulb, aquarium heater or touch lamp that causes all sorts of problems. The first thing I would do is look for noise sources. Find a spot on the radio that just crackles with noise and try to track down the source. 

My plasma TV is a real nuisance when I try to DX. Some computers are just noise generators. The solution, shut off the problems when you start a session. One method that works is to turn off all the circuit breakers in your house and then flick them on, individually, and listen for the noise. When you find one or more that has problems, then you DF in the areas those breakers serve. You will be surprised what kinds of things can cause problems. The wall wart charger on a portable phone or cordless razor, for instance. Light dimming switches are notorious. Microwave ovens or the digital displays on appliances have been known to radiate noise if you're too close.

And remember, all of this can vary from frequency to frequency. On some, the radio may just be overloaded. On others, the local may be operating out of its assigned bandwidth. I'd do that kind of work first before trying to gut the 380 and replace anything. You have to identify the problem before you can engineer the solution, I've always found.

Good luck. And don't just give up the radio. You might find a lot of fun taking it on summer vacation trips or discover a world of DX if you and your family go camping. And it's still a great SW and FM receiver and there's lots of DX fun available on those bands as well.



On Aug 4, 2010, at 12:57 AM, Stephen wrote:

 

So are there any tips, short of going to an alternate location, to try for international DX with my PL-380 and Select-A-Tenna? I live in a fairly RF-saturated environment, which doesn't help, and it's difficult, if not impossible, for me to travel to other locations at this time. (If I had the opportunity, I might want to try going to somewhere west of Santa Barbara, CA (on the California coast) to try for some DX, but that doesn't look like it will happen anytime in the near future.) For now, though, the maximum extent of my "DXpedition trek" would extend to my back yard on the 1/2-acre lot.
And, for "international", for purposes of this post, I'm not including Mexico - I can get several AM and FM stations 24/7, some of which peg the SNR meter, and one AM pegs the RSSI meter in the daytime as well.

Or, should I resign myself to never doing any meaningful DX from here, and sell my PL-380? I do remember Scott Willingham in a post last week or so mentioning something about 3 ways to improve selectivity, one of which was to install passive filtering in front of the DSP chip. Is doing something like that that even remotely a possibility? And, while I'm at it (if I was to attempt something like that), what about pulling the guts out of the PL-380 cabinet, substituting a separate loopstick (would have to be no longer than 3 to 4 inches long and 1/2 inch thick, assuming it takes the entire width and almost the entire thickness of the radio, as it will have to fit in my pants pocket and 4" is the absolute maximum width that would reasonably go in there - my PL-380 will go in there but it's awkward), and basically crafting my own vertically-oriented ultralight based on the PL-380's guts, or would it not even be considered in the "unlimited" category? :(

--- In ultralightdx@..., D1028Gary@... wrote:
>
> Hi Richard,
>
> Yes, I also wish you could have been in Oregon to enjoy the wild DXing
> fun-- chasing AM stations in Australia, New Zealand and the Pacific (from the
> west coast) is about the only way to have much AM-DXing fun in the middle of
> summer. It's kind of like a head start on the Fall Season!
>
> The 7.5" loopstick PL-360 would have received all the South Pacific DX at
> the same signal levels as the 7.5" loopstick PL-380, but with more domestic
> splatter in some cases (because of the fixed 3 kHz DSP selectivity in the
> PL-360). This wouldn't have happened in all cases, though, like in
> receiving 891-5AN, which had no domestic splatter anywhere nearby. The 7.5"
> loopstick PL-360 should be a fun radio for domestic DXing, where the selectivity
> requirements aren't as great as in 9 kHz-split DXing.
>
> 73, Gary
>
>
> In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time,
> richarda@... writes:
>
>
>
>
> Gary:
>
> Thanks for the report. I wish I could have been there to enjoy the DXing
> fun. It would have been nice to see how the PL-360/7.5" combo might have
> performed.
>
> Richard.
>
> Richard Allen
> 36°22'51N / 97°26'35"W
>



Gary DeBock
 

Hello Tony and Stephen,
 
Tony, that was a very profound and thorough discussion of a DXer's options in dealing with RF overload issues (certainly worthy of re-posting in our Ultralightdx file section in article form, if you are so inclined).
 
Stephen, like Tony says, if you are already having severe RF overload issues with your local pests, the last thing you should be doing is trying to boost the sensitivity of your ULR by going for larger loopsticks. Plastic-cabinet Ultralight radios lack the extensive RF shielding used in expensive communications receivers, which typically use coaxial antenna connectors and grounding posts to minimize the household RF hash coming from computers, plasma TV's, etc. Since we choose to use Ultralight radios anyway (despite this limitation), it is up to us to find solutions to RF overload problems.
 
There is a very good reason why DXpeditioners try to set up in isolated locations, far away from urban RF pests, and household RF hash. The 9 kHz-split DX signals from overseas are usually very weak in comparison to domestic pest stations, and serious domestic splatter or spurious products would be a deal-breaker. For Ultralight radio users, it is especially important to get away from these type of problems, since our radios lack the internal shielding and overload protection common in communications receivers. Frankly, Stephen, if you want better DXing results from overseas, your best option would be to "get out of Dodge," and head for an isolated ocean beach DXing location as far away as possible from urban RF blowtorches. Then you can reasonably consider mega-loopsticks, monster loops and/or beverages to boost up your weak-signal AM sensitivity.
 
Keep in mind that there is no perfect DXing location in California, or in any other state. I lived in San Diego from 1974-1975 while in the Navy, and even with many of the stations signing off at midnight, my impression was that the entire Southern California area was an RF hash zoo. We all need to do the best we can with the resources we have available, and my advice would be to just get started, and do the best you can on the AM frequencies that you have open. As long as you have reasonable expectations, you can still have plenty of DXing fun in the fall season as conditions improve.
 
73 and Good Luck,
Gary DeBock (in Puyallup, WA)                
 
 
 
In a message dated 8/4/2010 8:08:30 A.M. Pacific Daylight Time, germanotta.tony@... writes:

 

Stephen, you  keep asking the same question in different ways, but the answer can't change. If you are in an area where your portable radio is being overwhelmed by RF splatter from other stations, it's pretty much impossible to hear the, by definition, faint signals from DX stations. It's like trying to DX under the noise of a bad fluorescent bulb. I have one in a back room that just wipes out the entire band when I forget to turn it off. 


Can you build a preselector? Sure. What will it do. Well, there are types that peak up just one narrow band of frequencies. That helps sometimes, and others that block out either everything above its designed frequency or everything below. And those can help sometimes and some that just notch out one slice of the bandwidth. Again, it can help in some conditions. 

But if your area is buried by off-frequency splatter, which seems to be the case from your various postings, then none of those will help at all because the offending frequency will be on the same frequency you are trying to DX. If you filter it out, your DX is also blocked from the receiver. The FCC in recent years has become pretty lax on keeping AM stations to their specs, I have discovered. There just aren't that many folks like us out there who get offended by the local talk station bleeds over 10KHz, since there is usually no other local station on the air there. And the days of clear channel stations designed to cover wide sections of the country are over. Those frequencies are now shared by several stations with national coverage now something ceded to the internet, satellite radios or just not deemed a national priority anymore. 

You keep searching for more sensitivity when your problem is probably too much signal already. 

Changing out the internal ferrite won't help if it makes the radio more sensitive in an area already over washed by RF. What you might want to do is cut sensitivity some. That's easy on radio's with a DX/Local switch that puts an attenuator between the antenna and the front end. You can do that yourself on shortwave or FM with your radio, but the AM circuit doesn't have that kind of outside input unless you go to the little one with the external antenna jack. On that one, you could put a variable resistor, or Pot, in line and use that to cut signal. There are better ways to do it, with resistance boxes, if you find the rough method works. With your radio, the antenna is always in line. So you can try reducing signal by putting the radio in a grounded metal can, for instance, with just a small opening for RF to get through. That might reduce the RF to below the point where it is overwhelming the chip and causing it to do weird things by going what they call non-linear.  Before you do that, though, try to borrow a radio with an attenuator on board and see if it does anything for you. Again, if the locals are broadcasting over adjacent frequencies rather than your radio just being overwhelmed and reproducing them on those frequencies, attenuation won't help. It will just reduce both the DX and the local pest equally and the DX is going to be the loser, since it is much, much weaker. If the attenuation helps, then you know it's overload causing the majority of your problems. And you can build your attenuating can. 

Of course, you won't be able to fit that in your pants pocket. Then again, DXing isn't something you do while taking a walk. Moving a couple feet inside a house can make a ton of difference in DX sometimes because of the way the radio waves are being reflected and blocked by stuff in your walls an attic.  That said, sometimes heading to the far reaches of the back yard can improve things by getting away from near field RF noise. Then again, you may just be moving closer to the neighbor with the bad bulb, aquarium heater or touch lamp that causes all sorts of problems. The first thing I would do is look for noise sources. Find a spot on the radio that just crackles with noise and try to track down the source. 

My plasma TV is a real nuisance when I try to DX. Some computers are just noise generators. The solution, shut off the problems when you start a session. One method that works is to turn off all the circuit breakers in your house and then flick them on, individually, and listen for the noise. When you find one or more that has problems, then you DF in the areas those breakers serve. You will be surprised what kinds of things can cause problems. The wall wart charger on a portable phone or cordless razor, for instance. Light dimming switches are notorious. Microwave ovens or the digital displays on appliances have been known to radiate noise if you're too close.

And remember, all of this can vary from frequency to frequency. On some, the radio may just be overloaded. On others, the local may be operating out of its assigned bandwidth. I'd do that kind of work first before trying to gut the 380 and replace anything. You have to identify the problem before you can engineer the solution, I've always found.

Good luck. And don't just give up the radio. You might find a lot of fun taking it on summer vacation trips or discover a world of DX if you and your family go camping. And it's still a great SW and FM receiver and there's lots of DX fun available on those bands as well.



On Aug 4, 2010, at 12:57 AM, Stephen wrote:

 

So are there any tips, short of going to an alternate location, to try for international DX with my PL-380 and Select-A-Tenna? I live in a fairly RF-saturated environment, which doesn't help, and it's difficult, if not impossible, for me to travel to other locations at this time. (If I had the opportunity, I might want to try going to somewhere west of Santa Barbara, CA (on the California coast) to try for some DX, but that doesn't look like it will happen anytime in the near future.) For now, though, the maximum extent of my "DXpedition trek" would extend to my back yard on the 1/2-acre lot.
And, for "international", for purposes of this post, I'm not including Mexico - I can get several AM and FM stations 24/7, some of which peg the SNR meter, and one AM pegs the RSSI meter in the daytime as well.

Or, should I resign myself to never doing any meaningful DX from here, and sell my PL-380? I do remember Scott Willingham in a post last week or so mentioning something about 3 ways to improve selectivity, one of which was to install passive filtering in front of the DSP chip. Is doing something like that that even remotely a possibility? And, while I'm at it (if I was to attempt something like that), what about pulling the guts out of the PL-380 cabinet, substituting a separate loopstick (would have to be no longer than 3 to 4 inches long and 1/2 inch thick, assuming it takes the entire width and almost the entire thickness of the radio, as it will have to fit in my pants pocket and 4" is the absolute maximum width that would reasonably go in there - my PL-380 will go in there but it's awkward), and basically crafting my own vertically-oriented ultralight based on the PL-380's guts, or would it not even be considered in the "unlimited" category? :(

--- In ultralightdx@yahoogroups.com, D1028Gary@... wrote:
>
> Hi Richard,
>
> Yes, I also wish you could have been in Oregon to enjoy the wild DXing
> fun-- chasing AM stations in Australia, New Zealand and the Pacific (from the
> west coast) is about the only way to have much AM-DXing fun in the middle of
> summer. It's kind of like a head start on the Fall Season!
>
> The 7.5" loopstick PL-360 would have received all the South Pacific DX at
> the same signal levels as the 7.5" loopstick PL-380, but with more domestic
> splatter in some cases (because of the fixed 3 kHz DSP selectivity in the
> PL-360). This wouldn't have happened in all cases, though, like in
> receiving 891-5AN, which had no domestic splatter anywhere nearby. The 7.5"
> loopstick PL-360 should be a fun radio for domestic DXing, where the selectivity
> requirements aren't as great as in 9 kHz-split DXing.
>
> 73, Gary
>
>
> In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time,
> richarda@... writes:
>
>
>
>
> Gary:
>
> Thanks for the report. I wish I could have been there to enjoy the DXing
> fun. It would have been nice to see how the PL-360/7.5" combo might have
> performed.
>
> Richard.
>
> Richard Allen
> 3622'51N / 9726'35"W
>



Mike Mayer <mwmayer@...>
 

All,

 

Just to add to the information here, it is good to keep in mind that designing a radio is an exercise in making tradeoffs and compromises. Any one who is an engineer has had to deal with it every day. There is no perfect solution, only a compromise between competing and sometimes contradictory requirements. There is even a Wikipedia page about how engineers talk about the subject. It is the phrase Fast, Good, Cheap: pick any two:

 

http://en.wikipedia.org/wiki/Project_triangle

 

 

==========================================================
Mike Mayer
mwmayer@...


From: ultralightdx@... [mailto:ultralightdx@...] On Behalf Of D1028Gary@...
Sent: Wednesday, August 04, 2010 2:24 PM
To: ultralightdx@...
Subject: Re: [ultralightdx] Re: July 2010 Oregon Beach Ultralight DXpedition Report

 

 

Hello Tony and Stephen,

 

Tony, that was a very profound and thorough discussion of a DXer's options in dealing with RF overload issues (certainly worthy of re-posting in our Ultralightdx file section in article form, if you are so inclined).

 

Stephen, like Tony says, if you are already having severe RF overload issues with your local pests, the last thing you should be doing is trying to boost the sensitivity of your ULR by going for larger loopsticks. Plastic-cabinet Ultralight radios lack the extensive RF shielding used in expensive communications receivers, which typically use coaxial antenna connectors and grounding posts to minimize the household RF hash coming from computers, plasma TV's, etc. Since we choose to use Ultralight radios anyway (despite this limitation), it is up to us to find solutions to RF overload problems.

 

There is a very good reason why DXpeditioners try to set up in isolated locations, far away from urban RF pests, and household RF hash. The 9 kHz-split DX signals from overseas are usually very weak in comparison to domestic pest stations, and serious domestic splatter or spurious products would be a deal-breaker. For Ultralight radio users, it is especially important to get away from these type of problems, since our radios lack the internal shielding and overload protection common in communications receivers. Frankly, Stephen, if you want better DXing results from overseas, your best option would be to "get out of Dodge," and head for an isolated ocean beach DXing location as far away as possible from urban RF blowtorches. Then you can reasonably consider mega-loopsticks, monster loops and/or beverages to boost up your weak-signal AM sensitivity.

 

Keep in mind that there is no perfect DXing location in California, or in any other state. I lived in San Diego from 1974-1975 while in the Navy, and even with many of the stations signing off at midnight, my impression was that the entire Southern California area was an RF hash zoo. We all need to do the best we can with the resources we have available, and my advice would be to just get started, and do the best you can on the AM frequencies that you have open. As long as you have reasonable expectations, you can still have plenty of DXing fun in the fall season as conditions improve.

 

73 and Good Luck,

Gary DeBock (in Puyallup, WA)                

 

 

 

In a message dated 8/4/2010 8:08:30 A.M. Pacific Daylight Time, germanotta.tony@gmail.com writes:

 

Stephen, you  keep asking the same question in different ways, but the answer can't change. If you are in an area where your portable radio is being overwhelmed by RF splatter from other stations, it's pretty much impossible to hear the, by definition, faint signals from DX stations. It's like trying to DX under the noise of a bad fluorescent bulb. I have one in a back room that just wipes out the entire band when I forget to turn it off. 

 

Can you build a preselector? Sure. What will it do. Well, there are types that peak up just one narrow band of frequencies. That helps sometimes, and others that block out either everything above its designed frequency or everything below. And those can help sometimes and some that just notch out one slice of the bandwidth. Again, it can help in some conditions. 

 

But if your area is buried by off-frequency splatter, which seems to be the case from your various postings, then none of those will help at all because the offending frequency will be on the same frequency you are trying to DX. If you filter it out, your DX is also blocked from the receiver. The FCC in recent years has become pretty lax on keeping AM stations to their specs, I have discovered. There just aren't that many folks like us out there who get offended by the local talk station bleeds over 10KHz, since there is usually no other local station on the air there. And the days of clear channel stations designed to cover wide sections of the country are over. Those frequencies are now shared by several stations with national coverage now something ceded to the internet, satellite radios or just not deemed a national priority anymore. 

 

You keep searching for more sensitivity when your problem is probably too much signal already. 

 

Changing out the internal ferrite won't help if it makes the radio more sensitive in an area already over washed by RF. What you might want to do is cut sensitivity some. That's easy on radio's with a DX/Local switch that puts an attenuator between the antenna and the front end. You can do that yourself on shortwave or FM with your radio, but the AM circuit doesn't have that kind of outside input unless you go to the little one with the external antenna jack. On that one, you could put a variable resistor, or Pot, in line and use that to cut signal. There are better ways to do it, with resistance boxes, if you find the rough method works. With your radio, the antenna is always in line. So you can try reducing signal by putting the radio in a grounded metal can, for instance, with just a small opening for RF to get through. That might reduce the RF to below the point where it is overwhelming the chip and causing it to do weird things by going what they call non-linear.  Before you do that, though, try to borrow a radio with an attenuator on board and see if it does anything for you. Again, if the locals are broadcasting over adjacent frequencies rather than your radio just being overwhelmed and reproducing them on those frequencies, attenuation won't help. It will just reduce both the DX and the local pest equally and the DX is going to be the loser, since it is much, much weaker. If the attenuation helps, then you know it's overload causing the majority of your problems. And you can build your attenuating can. 

 

Of course, you won't be able to fit that in your pants pocket. Then again, DXing isn't something you do while taking a walk. Moving a couple feet inside a house can make a ton of difference in DX sometimes because of the way the radio waves are being reflected and blocked by stuff in your walls an attic.  That said, sometimes heading to the far reaches of the back yard can improve things by getting away from near field RF noise. Then again, you may just be moving closer to the neighbor with the bad bulb, aquarium heater or touch lamp that causes all sorts of problems. The first thing I would do is look for noise sources. Find a spot on the radio that just crackles with noise and try to track down the source. 

 

My plasma TV is a real nuisance when I try to DX. Some computers are just noise generators. The solution, shut off the problems when you start a session. One method that works is to turn off all the circuit breakers in your house and then flick them on, individually, and listen for the noise. When you find one or more that has problems, then you DF in the areas those breakers serve. You will be surprised what kinds of things can cause problems. The wall wart charger on a portable phone or cordless razor, for instance. Light dimming switches are notorious. Microwave ovens or the digital displays on appliances have been known to radiate noise if you're too close.

 

And remember, all of this can vary from frequency to frequency. On some, the radio may just be overloaded. On others, the local may be operating out of its assigned bandwidth. I'd do that kind of work first before trying to gut the 380 and replace anything. You have to identify the problem before you can engineer the solution, I've always found.

 

Good luck. And don't just give up the radio. You might find a lot of fun taking it on summer vacation trips or discover a world of DX if you and your family go camping. And it's still a great SW and FM receiver and there's lots of DX fun available on those bands as well.

 

 

 

On Aug 4, 2010, at 12:57 AM, Stephen wrote:



 

So are there any tips, short of going to an alternate location, to try for international DX with my PL-380 and Select-A-Tenna? I live in a fairly RF-saturated environment, which doesn't help, and it's difficult, if not impossible, for me to travel to other locations at this time. (If I had the opportunity, I might want to try going to somewhere west of Santa Barbara, CA (on the California coast) to try for some DX, but that doesn't look like it will happen anytime in the near future.) For now, though, the maximum extent of my "DXpedition trek" would extend to my back yard on the 1/2-acre lot.
And, for "international", for purposes of this post, I'm not including Mexico - I can get several AM and FM stations 24/7, some of which peg the SNR meter, and one AM pegs the RSSI meter in the daytime as well.

Or, should I resign myself to never doing any meaningful DX from here, and sell my PL-380? I do remember Scott Willingham in a post last week or so mentioning something about 3 ways to improve selectivity, one of which was to install passive filtering in front of the DSP chip. Is doing something like that that even remotely a possibility? And, while I'm at it (if I was to attempt something like that), what about pulling the guts out of the PL-380 cabinet, substituting a separate loopstick (would have to be no longer than 3 to 4 inches long and 1/2 inch thick, assuming it takes the entire width and almost the entire thickness of the radio, as it will have to fit in my pants pocket and 4" is the absolute maximum width that would reasonably go in there - my PL-380 will go in there but it's awkward), and basically crafting my own vertically-oriented ultralight based on the PL-380's guts, or would it not even be considered in the "unlimited" category? :(

--- In ultralightdx@yahoogroups.com, D1028Gary@... wrote:
>
> Hi Richard,
>
> Yes, I also wish you could have been in Oregon to enjoy the wild DXing
> fun-- chasing AM stations in Australia, New Zealand and the Pacific (from the
> west coast) is about the only way to have much AM-DXing fun in the middle of
> summer. It's kind of like a head start on the Fall Season!
>
> The 7.5" loopstick PL-360 would have received all the South Pacific DX at
> the same signal levels as the 7.5" loopstick PL-380, but with more domestic
> splatter in some cases (because of the fixed 3 kHz DSP selectivity in the
> PL-360). This wouldn't have happened in all cases, though, like in
> receiving 891-5AN, which had no domestic splatter anywhere nearby. The 7.5"
> loopstick PL-360 should be a fun radio for domestic DXing, where the selectivity
> requirements aren't as great as in 9 kHz-split DXing.
>
> 73, Gary
>
>
> In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time,
> richarda@... writes:
>
>
>
>
> Gary:
>
> Thanks for the report. I wish I could have been there to enjoy the DXing
> fun. It would have been nice to see how the PL-360/7.5" combo might have
> performed.
>
> Richard.
>
> Richard Allen
> 3622'51N / 9726'35"W
>

 


pianoplayer88key
 

Hmm... yeah, the band here isn't exactly as quiet as you might have found in the middle of the Pacific Ocean before Noah's Flood. :)

My main reason for boosting sensitivity is actually not for TP or TA DX'ing, although if it's needed to pick up the TIS, part 15-equivalent, etc. signals from across the pond, I might consider it. Really, though, I would like to be able to hear more distant stations in the daytime. My Select-A-Tenna-aided reception of KALL-700 North Salt Lake City - http://cid-6bdd1917662288cb.office.live.com/self.aspx/AM%20radio%20files/PL-380%20March%202010%20%5E51%5E6/maybe%20700%20KALL%20-%20PL-380%20-%202010-03-08%203pm.mp3 - at around 2 or 3pm one day in March was a step in the right direction, but I'm still looking for other more distant stations.

Some of the stations I'd like to be able to listen to in the daytime, either from home or from around town, include, but are not limited to:

KFYI-550 Phoenix, AZ - 289mi, 80°, 5kW ND (pest: XESURF-540 Tijuana, BCN - RSSI/SNR 45/25)
KSAZ-580 Marana, AZ - 330mi, 92°, 5kW ND
KWVE-660 Oildale, CA - 218mi, 329°, 8kW DA, 260mV/m@1km
KNBR-680 San Francisco, CA - 445mi, 319°, 50kW ND
(pest: XETRA-690 Rosarito, BCN - 32mi, 189°, 77kW DA, 4128mV/m@1km, RSSI/SNR 63/25 (my PL-380 caps both at those values))
KALL-700 North Salt Lake City, UT - 626mi, 25°, 50kW DA, 4259mV/m@1km
KDWN-720 Las Vegas, NV - 255mi, 26°, 50kW ND
KXL-750 Portland, OR - 921mi, 343°, 50kW DA, 1788mV/m@1km
(pest: KFMB-760 San Diego, CA - 7mi, 321°. 5kW ND, RSSI/SNR 63/25)
KCBC-770 Manteca, CA - 413mi, 329°, 50kW DA, 1037mV/m@1km
KAZM-780 Sedona, AZ - 328mi, 62°, 5kW ND
KGO-810 San Francisco, CA - 440mi, 320°, 50kW DA, 3442mV/m@1km (pest: XESPN-800 Tijuana, BCN - 18mi, 193°, 1kW ND, RSSI/SNR 52/25)
KXNT-840 North Las Vegas, NV - 277mi, 34°, 50kW DA, 4684mV/m@1km
KLFF-890 Arroyo Grande, CA - 263mi, 310°, 5kW ND
KPSI-920 Palm Springs, CA - 80mi, 19°, 5kW DA, 354mV/m@1km (pest: KECR-910 El Cajon, CA - 9mi, 7°, 5kW DA, 602.84mV/m@1km, RSSI/SNR 63/25)
KYNO-940 Fresno, CA - 291mi, 333°, 50kW DA, 1214mV/m@1km
(pest: XEKAM-950 Rosarito, BCN - 25mi, 200°, 20kW (ND/DA?), RSSI/SNR 51/25)
KIXW-960 Apple Valley, CA - 122mi, 353°, 5kW ND (This is receivable here: http://cid-6bdd1917662288cb.office.live.com/self.aspx/AM%20radio%20files/2010-07-20/0960%20KIXW%20Apple%20Valley%5EJ%20CA.mp3 , but extremely weak - barefoot RSSI & SNR is 30,00 or 32,00.)
KNWZ-970 Coachella, CA - 78mi, 35°, 5kW DA, 1188mV/m@1km
KFWB-980 Los Angeles, CA - 116mi, 322°, 5kW ND
KXPS-1010 Thousand Palms, CA - 81mi, 22°, 3.6kW DA, 275mV/m@1km
KFNX-1100 Cave Creek, AZ - 295mi, 75°, 50kW DA, 2016mV/m@1km (pest: XEPRS-1090 Rosarito, BCN - 26mi, 198°, 50kW ND (but probably uses DA - 954mV/m@1km, RSSI/SNR 50/25)
KDIS-1110 Pasadena, CA - 111mi, 327°, 50kW DA, 3076mV/m@1km (This is very faint here, under a reading of 41,00 or 43,00 approximately. If I could get improved reception of this station (by having a better filter in front of the Si4734 that would help reduce the desense from KSDO-1130 and KCBQ-1170), that would be nice, if I can't pull in one I'll list on 1290 that itself would have a pest.)
KNWQ-1140 Palm Springs, CA - 81mi, 20°, 10kW DA, 1232mV/m@1km (pest: KDSO-1130 San Diego, CA - 6mi, 350°, 10kW DA, 1070mV/m@1km, RSSI/SNR 63/25)
KTLK-1150 Los Angeles, CA - 106mi, 326°, 50kW DA, 498mV/m@1km
KERN-1180 Wasco-Greenacres, CA - 237mi, 326°, 50kW DA, 2704mV/m@1km (pest: KCBQ-1170 San Diego, CA - 9mi, 7°, 50kW DA, 3738mV/m@1km, RSSI/SNR 63/25)
KXO-1230 El Centro, CA - 81mi, 87°, 0.83kW ND
KGIL-1260 Beverly Hills, CA - 135mi, 320°, 20kW DA, 1050mV/m@1km (pest: XEAZ-1270 Tijuana, BCN - 16mi, 201°, 0.5kW ND, RSSI/SNR 46/25)
KKDD-1290 San Bernardino, CA - 96mi, 350°, 5kW DA, 758mV/m@1km (Unlike KDIS-1110 and KMIK-1580, this one broadcasts the full 10kHz analog bandwidth. Unfortunately, KZSB Santa Barbara could prove to provide stiff competition, as it is usually the dominant station on the frequency, in spite of being 1/10th the power and about twice the distance.)
KCLU-1340 Santa Barbara, CA - 195mi, 307°, 0.65kW ND (This one can be faintly heard barefoot - http://cid-6bdd1917662288cb.office.live.com/self.aspx/AM%20radio%20files/2010-07-20/1340%20KCLU%20Santa%20Barbara%5EJ%20CA.mp3 , but improved barefoot reception would be nice.)
KTDD-1350 San Bernardino, CA - 94mi, 348°, 5kW DA, 552mV/m@1km (pest: KLSD-1360 San Diego, CA - 8mi, 255°, 5kW ND, RSSI/SNR 63/25)
KKZZ-1400 Santa Paula, CA - 164mi, 312°, 1kW ND (pest: XEKT-1390 Tecate, BCN - 22mi, 137°, 5kW or 10kW ND, RSSI/SNR 42/25)
KWST-1430 El Centro, CA - 82mi, 87°, 1kW ND
KUHL-1440 Santa Maria, CA - 253mi, 308°, 5kW ND (although KDIF Riverside, CA may dominate the frequency instead)
KTYM-1460 Inglewood, CA - 119mi, 317°, 5kW DA, 326mV/m@1km (pest: XERCN-1470 Tijuana, BCN - 18mi, 183°, 5kW or 10kW ND, RSSI/SNR 55/25)
KSPE-1490 Santa Barbara, CA - 195mi, 307°, 1kW ND
KSPA-1510 Ontario, CA - 100mi, 338°, 10kW DA, 1338mV/m@1km
KVTA-1520 Port Hueneme, CA - 159mi, 308°, 10kW DA, 1169mV/m@1km (can be received barefoot, but is extremely faint)
KFBK-1530 Sacramento, CA - 491mi, 330°, 50kW DA, 4447mV/m@1km
KNZR-1560 Bakersfield, CA - 213mi, 326°, 25kW ND
KMIK-1580 Tempe, AZ - 300mi, 79°, 50kW ND (KBLA Santa Monica, CA, normally dominates the frequency in the daytime, though.)

I know of people who have received stations over a thousand miles distant in the middle of the day, so I would think reception of at least some of the stations on the above list should be possible, provided I have narrow enough filters in front of the Si4734 chip to reject the adjacent locals. (One example would be wanting fairly clean reception of KERN-1180, with 50kW KCBQ-1170 being only 9 miles away.) Fortunately I only have one AM IBOC local - KOGO-600. I didn't specify any stations on 590 or 610 that I want to receive (although if I had an antenna that could null KOGO's IBOC, I have logged KAVL-610 Lancaster, CA ( http://cid-6bdd1917662288cb.office.live.com/self.aspx/AM%20radio%20files/PL-380%20March%202010%20%5E52%5E6/0610%20AM%20PL-380%20%5EM%20SAT%20%5E5KAVL%5E6.mp3 ), and one on 620 that I would like (KTAR-620 Phoenix, AZ) would get swamped by a co-channel local.


As for a DX'ing location... here's a linked picture of where I would go if I went outside in my back yard (leeched from Google Maps):
http://picasaweb.google.com/PianoPlayer88Key/RadioPicsStuff?authkey=Gv1sRgCIer0efojpPg8AE#5501810777831424738
The arrow points to where I would likely attempt my DXing. Would the fact that there are several stations that peg the RSSI meter at 63dBu barefoot be a major cause for concern? (There are spots on the dial where the RSSI/SNR between channels is upwards of 35/00 to 41/00 or so.) At least I'm not trying to DX from my grandparents' place near L.A. - they're about 1/3 mile from two major pests, one of them a 50kW which according to the Zip Signal site puts a mean 3.15V/m signal in the area and is 1kHz removed from a 9kHz frequency.
As for here, the local 63/25 pests are KOGO-600 (IBOC), XETRA-690 (a little less at night though), KFMB-760, KECR-910, KSDO-1130, KCBQ-1170 (a little less at night), and KLSD-1360. Other lesser pests include XESURF-540, XESS-620, KFI-640 (IBOC), KTNN-660 night, KDWN-720 night, KBRT-740 day or KCBS-740 night (both IBOC), XESPN-800, KLAA-830, KXNT-840 night (IBOC?), XEMO-860, XEKAM-950, XESDD-1030, KURS-1040, KNX-1070 (IBOC), XEPRS-1090, KPRZ-1210, KNSN-1240, XEAZ-1270, XEC-1310, XEKT-1390, XEXX-1420, XERCN-1470, KFBK-1530 night, KNZR-1560 night, KMIK-1580 (IBOC) and KBLA-1580 night, XEUT-1630 (I think they sign off late at night though) and XEPE-1700. Off-channel RSSI is typically around 30dBu across much of the band, with some places touching 41 to 45dBu near the strongest stations. It does drop some at the band edges, though, with 520kHz being around 17dBu and 1710kHz being around 22dBu (XEPE-1700 is typically 49-50dBu). The LW and SW bands typically show 15dBu readings on frequencies where there are no stations received.

In a location like that, N7EKX, would antennas like what you can probably make out in the picture linked below help at all?
http://picasaweb.google.com/PianoPlayer88Key/RadioPicsStuff?authkey=Gv1sRgCIer0efojpPg8AE#5501810775115393474

I'm currently limping along with only a Select-A-Tenna, which isn't nearly selective enough. I seem to remember you have one local pest that gives 89/25 readings, and is 1kHz removed from a 9kHz channel. Is it possible, with the PVC antennas, to hear any DX on that channel, assuming you're NOT attempting it with the Sony SRF-M37?

Alternatively, it could be an excuse for my family and friends to make a trip to a local beach location (San Elijo State Beach near Encinitas, CA) that we haven't been to in several years. However, that's probably not exactly a perfectly quiet location, either. I remember one time I had a radio shack project kit, and built a crystal radio with it. I was able to hear a few stations using only maybe a few meters of wire as an antenna, one being KNX-1070. Would the ability to hear multiple stations on a crystal set with only a few meters of wire antenna be an indicator that the location isn't exactly prime for international DX?
If I had to travel out of the area (which wouldn't happen anytime soon), would a place on the southern California coast about 30 or so miles west of Santa Barbara, CA (approximately where US Route 101 turns north and leaves the coast for a while), be far enough from the RF Zoo that is Los Angeles & San Diego?

Basically, here, my issue isn't so much a lack of weak-signal sensitivity (although my wanting to hear several stations at least a few hundred miles away in the daytime probably would indicate otherwise), but my PL-380's lack of front-end selectivity to deal with my local pests. I won't go into detail like I have in the past, but I have a Panasonic RQ-SW20, which normally has selectivity comparable to the Sony SRF-M37, and generally inferior sensitivity to the stock PL-380. While extremely strong stations will splatter all over the band, there are several stations I have heard fairly well on the RQ-SW20 that were non-existant on the PL-380, when near strong local stations. I also have an older Zenith portable radio (not an ultralight by any stretch of the imagination) that has a tuned RF amplifier in front of the local oscillator, and based on some brief comparisons I've done, its front-end selectivity beats the Panasonic.
Also, I really would like to be able to access ALL the parameters, settings, etc. that are supported by the Si4734 chip, not to mention the fact that in my RF Zoo it really needs some good filters in front of the chip. (I do want to be able to take advantage of multiple bandwidths, though, so I don't really know what to do about that.) If there's a way I could do it in a package a comparable size to the PL-380, but in a vertical orientation (with the loopstick taking up pretty much the entire width of the case), that would be really nice.

Are there other TP frequencies I should try for when conditions improve? Many of the frequencies that are listed in the First Thrilling TP article are swamped by domestics. For example, 594 gets owned by a 5kW IBOC on 600 7 miles away, 639 is right next to KFI, 693 is too close to XEWW (or XETRA) 747 and 774 get swamped under 760, with RSSI 41dBu, SNR 0dB, 1575 gets owned by an IBOC KMIK at night, just to name a few.

In the meantime, though, I'm really interested in improving my daytime groundwave DX reception, as that's really the type of DX I'm interested in. As for the above list I posted, I don't expect to be able to hear all those stations barefoot, of course, but I would like to be able to hear most of them if I use the Select-A-Tenna, and probably all if I build one of the medium-size or larger PVC loops. For barefoot reception, though, I would like to be able to hear most of the weaker signals within 150-200 miles, and the 50kW signals within about 400-500 miles or so. Also, as for closer and more powerful signals, I would like nearby 50kW L.A. stations like KNX-1070 (111mi) and KFI-640 (99mi) to have clean, noise-free audio, so that unless you look at the RSSI meter or tune off frequency to see how wide the radio is desensitized, you can't aurally tell the difference in SNR between those and a local 50kW blowtorch like KCBQ-1170, for example, when received barefoot.

As for improving the situation IN the house, if I could quiet some of the appliances without needing to turn them off, that would be nice. I typically leave my computer on 24/7, by the way. Last time there was a power outage here, it didn't seem like the noise level got all that much lower.

And, as far as DX'ing not being something I do while on a walk... many of the stations I would like to listen to normally actually are marginal at best, and in some cases totally undetectable on my barefoot PL-380.

So, considering Scott's comments in message #10305, would one option possibly be installing some passive filter in front of the DSP chip? Also I'd be open to the idea of modifying the existing circuit to have a better dynamic range at the expense of power consumption (I would target a battery life of maybe about 4 to 5 hours), as long as I have an option to turn the extended dynamic range off.


I'm realizing that now is probably not exactly the best time of year for me to try for TP reception, and I should probably hold off till fall or winter. In the meantime, though, I would really like to improve my daytime reception, especially out from around local pests. Reducing sensitivity would be a detriment, though, as many of the stations I would like to be able to listen to (not necessarily barefoot, though), would be completely unreceivable on my barefoot PL-380 even if the nearby local pests were off the air.

Is there any hope for me for trying TA reception from here? The couple frequences I'm aware of have two of my strongest local blowtorches nearby - 1134 vs. KSDO-1130, and 756 or 765 vs. KFMB-760.

I also have yet to definitively log my first Canadian. A few nights ago, I thought I may have had reception on my barefoot PL-380 of CKWX-1130 Vancouver, BC, but the audio was marginal. I heard pieces of what sounded like a man's voice giving a newscast, based on the tone and inflection of his voice, but I think there was another station fighting with it. As I was listening to the frequency for several minutes, eventually a religious station, which I knew to be KRDU-1130 Dinuba, CA, started coming out on top, with a man's voice preaching a sermon. Of course, a while later, my local 10kW co-channel blowtorch 6 miles away, KSDO, got their transmitter back up and running. Any suggestions on how I could possibly receive CKWX, or would I have better luck with other Canadian frequences from that area? Most of the Canadian stations from the Victoria/Vancouver area have local/nearby co-channel or adjacent pests.

I will agree, though, that the FM reception on this radio is actually quite good. For example, I can consistently receive at least one FM station over 200 miles away, KVYB-103.3 Santa Barbara, CA. Just a few minutes ago, I was getting RSSI/SNR readings of 15/04.

Another note regarding AM sensitivity... I would rather have multiple stations fighting it out in the daytime, than have channels on which no daytime station is received.

--- In ultralightdx@..., D1028Gary@... wrote:

Hello Tony and Stephen,

Tony, that was a very profound and thorough discussion of a DXer's options
in dealing with RF overload issues (certainly worthy of re-posting in our
Ultralightdx file section in article form, if you are so inclined).

Stephen, like Tony says, if you are already having severe RF overload
issues with your local pests, the last thing you should be doing is trying to
boost the sensitivity of your ULR by going for larger loopsticks.
Plastic-cabinet Ultralight radios lack the extensive RF shielding used in expensive
communications receivers, which typically use coaxial antenna connectors and
grounding posts to minimize the household RF hash coming from computers,
plasma TV's, etc. Since we choose to use Ultralight radios anyway (despite
this limitation), it is up to us to find solutions to RF overload problems.

There is a very good reason why DXpeditioners try to set up in isolated
locations, far away from urban RF pests, and household RF hash. The 9
kHz-split DX signals from overseas are usually very weak in comparison to domestic
pest stations, and serious domestic splatter or spurious products would be
a deal-breaker. For Ultralight radio users, it is especially important to
get away from these type of problems, since our radios lack the internal
shielding and overload protection common in communications receivers.
Frankly, Stephen, if you want better DXing results from overseas, your best option
would be to "get out of Dodge," and head for an isolated ocean beach DXing
location as far away as possible from urban RF blowtorches. Then you can
reasonably consider mega-loopsticks, monster loops and/or beverages to boost
up your weak-signal AM sensitivity.

Keep in mind that there is no perfect DXing location in California, or in
any other state. I lived in San Diego from 1974-1975 while in the Navy, and
even with many of the stations signing off at midnight, my impression was
that the entire Southern California area was an RF hash zoo. We all need to
do the best we can with the resources we have available, and my advice
would be to just get started, and do the best you can on the AM frequencies
that you have open. As long as you have reasonable expectations, you can still
have plenty of DXing fun in the fall season as conditions improve.

73 and Good Luck,
Gary DeBock (in Puyallup, WA)




In a message dated 8/4/2010 8:08:30 A.M. Pacific Daylight Time,
germanotta.tony@... writes:




Stephen, you keep asking the same question in different ways, but the
answer can't change. If you are in an area where your portable radio is being
overwhelmed by RF splatter from other stations, it's pretty much impossible
to hear the, by definition, faint signals from DX stations. It's like
trying to DX under the noise of a bad fluorescent bulb. I have one in a back
room that just wipes out the entire band when I forget to turn it off.


Can you build a preselector? Sure. What will it do. Well, there are types
that peak up just one narrow band of frequencies. That helps sometimes, and
others that block out either everything above its designed frequency or
everything below. And those can help sometimes and some that just notch out
one slice of the bandwidth. Again, it can help in some conditions.


But if your area is buried by off-frequency splatter, which seems to be
the case from your various postings, then none of those will help at all
because the offending frequency will be on the same frequency you are trying to
DX. If you filter it out, your DX is also blocked from the receiver. The
FCC in recent years has become pretty lax on keeping AM stations to their
specs, I have discovered. There just aren't that many folks like us out there
who get offended by the local talk station bleeds over 10KHz, since there
is usually no other local station on the air there. And the days of clear
channel stations designed to cover wide sections of the country are over.
Those frequencies are now shared by several stations with national coverage
now something ceded to the internet, satellite radios or just not deemed a
national priority anymore.


You keep searching for more sensitivity when your problem is probably too
much signal already.


Changing out the internal ferrite won't help if it makes the radio more
sensitive in an area already over washed by RF. What you might want to do is
cut sensitivity some. That's easy on radio's with a DX/Local switch that
puts an attenuator between the antenna and the front end. You can do that
yourself on shortwave or FM with your radio, but the AM circuit doesn't have
that kind of outside input unless you go to the little one with the external
antenna jack. On that one, you could put a variable resistor, or Pot, in
line and use that to cut signal. There are better ways to do it, with
resistance boxes, if you find the rough method works. With your radio, the antenna
is always in line. So you can try reducing signal by putting the radio in
a grounded metal can, for instance, with just a small opening for RF to get
through. That might reduce the RF to below the point where it is
overwhelming the chip and causing it to do weird things by going what they call
non-linear. Before you do that, though, try to borrow a radio with an
attenuator on board and see if it does anything for you. Again, if the locals are
broadcasting over adjacent frequencies rather than your radio just being
overwhelmed and reproducing them on those frequencies, attenuation won't help.
It will just reduce both the DX and the local pest equally and the DX is
going to be the loser, since it is much, much weaker. If the attenuation
helps, then you know it's overload causing the majority of your problems. And
you can build your attenuating can.


Of course, you won't be able to fit that in your pants pocket. Then again,
DXing isn't something you do while taking a walk. Moving a couple feet
inside a house can make a ton of difference in DX sometimes because of the way
the radio waves are being reflected and blocked by stuff in your walls an
attic. That said, sometimes heading to the far reaches of the back yard
can improve things by getting away from near field RF noise. Then again, you
may just be moving closer to the neighbor with the bad bulb, aquarium heater
or touch lamp that causes all sorts of problems. The first thing I would
do is look for noise sources. Find a spot on the radio that just crackles
with noise and try to track down the source.


My plasma TV is a real nuisance when I try to DX. Some computers are just
noise generators. The solution, shut off the problems when you start a
session. One method that works is to turn off all the circuit breakers in your
house and then flick them on, individually, and listen for the noise. When
you find one or more that has problems, then you DF in the areas those
breakers serve. You will be surprised what kinds of things can cause problems.
The wall wart charger on a portable phone or cordless razor, for instance.
Light dimming switches are notorious. Microwave ovens or the digital
displays on appliances have been known to radiate noise if you're too close.


And remember, all of this can vary from frequency to frequency. On some,
the radio may just be overloaded. On others, the local may be operating out
of its assigned bandwidth. I'd do that kind of work first before trying to
gut the 380 and replace anything. You have to identify the problem before
you can engineer the solution, I've always found.


Good luck. And don't just give up the radio. You might find a lot of fun
taking it on summer vacation trips or discover a world of DX if you and your
family go camping. And it's still a great SW and FM receiver and there's
lots of DX fun available on those bands as well.






On Aug 4, 2010, at 12:57 AM, Stephen wrote:




So are there any tips, short of going to an alternate location, to try for
international DX with my PL-380 and Select-A-Tenna? I live in a fairly
RF-saturated environment, which doesn't help, and it's difficult, if not
impossible, for me to travel to other locations at this time. (If I had the
opportunity, I might want to try going to somewhere west of Santa Barbara, CA
(on the California coast) to try for some DX, but that doesn't look like it
will happen anytime in the near future.) For now, though, the maximum
extent of my "DXpedition trek" would extend to my back yard on the 1/2-acre lot.
And, for "international"And, for "international"<WBR>, for purposes of this
post, I'm not including Mexico - I can get several AM and FM stations
24/7, some of which peg the SNR meter, and one AM pegs the RSSI meter

Or, should I resign myself to never doing any meaningful DX from here, and
sell my PL-380? I do remember Scott Willingham in a post last week or so
mentioning something about 3 ways to improve selectivity, one of which was
to install passive filtering in front of the DSP chip. Is doing something
like that that even remotely a possibility? And, while I'm at it (if I was to
attempt something like that), what about pulling the guts out of the
PL-380 cabinet, substituting a separate loopstick (would have to be no longer
than 3 to 4 inches long and 1/2 inch thick, assuming it takes the entire
width and almost the entire thickness of the radio, as it will have to fit in
my pants pocket and 4" is the absolute maximum width that would reasonably
go in there - my PL-380 will go in there but it's awkward), and basically
crafting my own vertically-oriented ultralight based on the PL-380's guts, or
would it not even be considered in the "unlimited" category? :(

--- In _ultralightdx@ultralightdxult_ (mailto:ultralightdx@...)
, D1028Gary@,

Hi Richard,

Yes, I also wish you could have been in Oregon to enjoy the wild DXing
fun-- chasing AM stations in Australia, New Zealand and the Pacific
(from the
west coast) is about the only way to have much AM-DXing fun in the
middle of
summer. It's kind of like a head start on the Fall Season!

The 7.5" loopstick PL-360 would have received all the South Pacific DX
at
the same signal levels as the 7.5" loopstick PL-380, but with more
domestic
splatter in some cases (because of the fixed 3 kHz DSP selectivity in
the
PL-360). This wouldn't have happened in all cases, though, like in
receiving 891-5AN, which had no domestic splatter anywhere nearby. The
7.5"
loopstick PL-360 should be a fun radio for domestic DXing, where the
selectivity
requirements aren't as great as in 9 kHz-split DXing.

73, Gary


In a message dated 8/3/2010 4:41:46 P.M. Pacific Daylight Time,
richarda@ writes:




Gary:

Thanks for the report. I wish I could have been there to enjoy the DXing
fun. It would have been nice to see how the PL-360/7.5" combo might have
performed.

Richard.

Richard Allen
3622'51N / 9726'35"W