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Re: Hi from a new member with a question.
OK Steven,
Actually I sent my message before seeing Steve's responses to your original post. Steve was experimenting with FSL antennas even before I started, and we have shared ideas and resources for many years. He is one of the top experts in FSL antennas, and all of his recommendations come from many years of experience.
73, Gary
-----Original Message----- From: Steven mont633@... [ultralightdx] To: ultralightdx Sent: Sun, Jan 29, 2017 11:11 pm Subject: Re: [ultralightdx] Hi from a new member with a question. Hi Gary,
Thank you for the info and advice, thanks very much also for the offer of the foam, but I should be able to track down a suitable thickness of dielectric here somewhere.
I will report back with my findings once I re wind my coil.
Thanks again.
regards,
Steven.
Hi Steven,
<<< My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods.
At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. >>> This is Gary, one of the early FSL experimenters.
You can probably get a performance boost in your antenna by rewinding your coil over about 6mm of insulating foam, separating the coil and the ferrite rods. There was quite a bit of experimentation with this after Graham Maynard's initial ferrite sleeve article was published in 2011, and this concept was confirmed by multiple experimenters. If have any difficulty tracking down this type of foam in Scotland, I would be happy to send you a pack free of charge (it's pretty cheap).
Good Luck,
Gary DeBock, N7EKX (in Puyallup, WA, USA)
-----Original Message-----
From: mont633@... [ultralightdx] <ultralightdx@...> To: ultralightdx <ultralightdx@...> Sent: Sun, Jan 29, 2017 4:51 am Subject: [ultralightdx] Hi from a new member with a question. Hello,
I have just found your group and joined to day. I live in Scotland, UK. I found your group while googling about ferrite sleeve antennas, I am also a memeber of several other yahoo groups. I have made a few air cored loops or magnetic loop antennas and have had great results. Yesterday I made an approx 4" dia ferrite sleeve antenna with 30 off 10 mm x 140mm rods. I am pleased with the results, and checks last night showed that it is on a par with a 2 foot air cored loop I made. My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods. At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. Thanks very much in advance for any help or info. Regards, Steven. Scotland.
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Re: Hi from a new member with a question.
steven
Hi Gary, Thank you for the info and advice, thanks very much also for the offer of the foam, but I should be able to track down a suitable thickness of dielectric here somewhere. I will report back with my findings once I re wind my coil. Thanks again. regards, Steven.
On Monday, 30 January 2017, 4:33, "D1028Gary@... [ultralightdx]" wrote: Hi Steven,
<<< My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods.
At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. >>> This is Gary, one of the early FSL experimenters.
You can probably get a performance boost in your antenna by rewinding your coil over about 6mm of insulating foam, separating the coil and the ferrite rods. There was quite a bit of experimentation with this after Graham Maynard's initial ferrite sleeve article was published in 2011, and this concept was confirmed by multiple experimenters. If have any difficulty tracking down this type of foam in Scotland, I would be happy to send you a pack free of charge (it's pretty cheap).
Good Luck,
Gary DeBock, N7EKX (in Puyallup, WA, USA)
-----Original Message-----
From: mont633@... [ultralightdx] To: ultralightdx Sent: Sun, Jan 29, 2017 4:51 am Subject: [ultralightdx] Hi from a new member with a question. Hello,
I have just found your group and joined to day. I live in Scotland, UK. I found your group while googling about ferrite sleeve antennas, I am also a memeber of several other yahoo groups. I have made a few air cored loops or magnetic loop antennas and have had great results. Yesterday I made an approx 4" dia ferrite sleeve antenna with 30 off 10 mm x 140mm rods. I am pleased with the results, and checks last night showed that it is on a par with a 2 foot air cored loop I made. My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods. At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. Thanks very much in advance for any help or info. Regards, Steven. Scotland.
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Re: Hi from a new member with a question.
Hi Steven,
<<< My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods.
At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. >>> This is Gary, one of the early FSL experimenters.
You can probably get a performance boost in your antenna by rewinding your coil over about 6mm of insulating foam, separating the coil and the ferrite rods. There was quite a bit of experimentation with this after Graham Maynard's initial ferrite sleeve article was published in 2011, and this concept was confirmed by multiple experimenters. If have any difficulty tracking down this type of foam in Scotland, I would be happy to send you a pack free of charge (it's pretty cheap).
Good Luck,
Gary DeBock, N7EKX (in Puyallup, WA, USA)
-----Original Message----- From: mont633@... [ultralightdx] To: ultralightdx <ultralightdx@...> Sent: Sun, Jan 29, 2017 4:51 am Subject: [ultralightdx] Hi from a new member with a question. Hello,
I have just found your group and joined to day. I live in Scotland, UK. I found your group while googling about ferrite sleeve antennas, I am also a memeber of several other yahoo groups. I have made a few air cored loops or magnetic loop antennas and have had great results. Yesterday I made an approx 4" dia ferrite sleeve antenna with 30 off 10 mm x 140mm rods. I am pleased with the results, and checks last night showed that it is on a par with a 2 foot air cored loop I made. My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods. At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. Thanks very much in advance for any help or info. Regards, Steven. Scotland.
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Re: Hi from a new member with a question. (coil spacing off the ferrite)
steven
Hi Steve, Thanks again for all the info, I will endeavour to get a hold of some of the appropriate Litz wire and see what improvement that makes over my stranded copper insulated wire. I have had a look at the files section and found some very interesting bed time reading, thanks for that too. Just before bed, I had a quick listen about on MW and at present I am receiving the station Carribean Beacon on 1610 AM with my FSL antenna indoors, a quick google tells me that the distance from my QTH in Scotland to Anguilla in the Carribean is 3968 miles, so I will be keen to see the difference with some Lits wire as a coil and a suitable dielectic wrapping. Thanks very much again. 73 Steven. Scotland.
On Sunday, 29 January 2017, 17:51, "Steve Ratzlaff ratzlaffsteve@... [ultralightdx]" wrote: Hi Steven,
As you note, of course air is the lowest loss spacer but it's not
very easy to wind a coil spaced over ferrite using just air.
:) Styrofoam is probably the next least-lossy dielectric, and
can often be found in sheets of varying thickness where a single
layer or maybe several layers add up to the correct coil spacing.
As for Litz, if you can obtain some, try to get as many strands of
#46 gauge as your budget allows. I would suggest that a minimum of
100 strands of Litz be used (100/46) otherwise the improvement
over using plain non-Litz wire won't be much. 175/46 and 330/46
are common sizes and are good choices, with 330/46 working better.
And then there's the "Big Litz" such as 660/46 which works even
better but which is much more expensive. Also remember the larger
Litz is larger in diameter so make sure your coil form width can
handle the extra winding width, and also that you will need
somewhat more turns for the larger size Litz you use, to tune the
same frequency range using the same variable capacitor since the
inductance for a given number of turns will decrease the larger
the wire diameter that is used.
Good luck and please keep us informed of your experiments and
results! And it must be fun to listen to Radio Caroline live;
you're fortunate to be able to receive the signal, even in
daytime.
73,
Steve AA7U
Arizona, USA
On 1/29/2017 10:17 AM, Steven
mont633@... [ultralightdx] wrote:
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Re: Hi from a new member with a question. (coil spacing off the ferrite)
Steve Ratzlaff
Hi Steven, As you note, of course air is the lowest loss spacer but it's not very easy to wind a coil spaced over ferrite using just air. :) Styrofoam is probably the next least-lossy dielectric, and can often be found in sheets of varying thickness where a single layer or maybe several layers add up to the correct coil spacing. As for Litz, if you can obtain some, try to get as many strands of #46 gauge as your budget allows. I would suggest that a minimum of 100 strands of Litz be used (100/46) otherwise the improvement over using plain non-Litz wire won't be much. 175/46 and 330/46 are common sizes and are good choices, with 330/46 working better. And then there's the "Big Litz" such as 660/46 which works even better but which is much more expensive. Also remember the larger Litz is larger in diameter so make sure your coil form width can handle the extra winding width, and also that you will need somewhat more turns for the larger size Litz you use, to tune the same frequency range using the same variable capacitor since the inductance for a given number of turns will decrease the larger the wire diameter that is used. Good luck and please keep us informed of your experiments and
results! And it must be fun to listen to Radio Caroline live;
you're fortunate to be able to receive the signal, even in
daytime. 73, Steve AA7U Arizona, USA
On 1/29/2017 10:17 AM, Steven
mont633@... [ultralightdx] wrote:
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Re: Hi from a new member with a question. (coil spacing off the ferrite)
steven
Hi, Thanks very much for all the replies to my question. I will remove the winding and add something to give the correct "air gap" to 1/4"-5/16", and see how that goes, I will also get a hold of some Litz wire as I have seen it on ebay. I have been using my ferrite sleeve antenna most of the day to listen to Radio Caroline live from the MV Ross Revenge via Manx Radio in the Isle of Man on 1368 kHz AM. I am over 100 miles from the Isle of Man, but with my ferrite sleeve antenna or one of my air core loops the ground wave signal is good readable at my location in Scotland. Thanks very much again for the help and advice. 73 Steven. Scotland.
On Sunday, 29 January 2017, 15:07, "Steve Ratzlaff ratzlaffsteve@... [ultralightdx]" wrote: Hi Steven,
Congrats on your first FSL success. Some of us have determined,
back when FSLs were first heard about and lots of experimentation
was going on, that the coil should be spaced about 1/4" to about
5/16" off the ferrite for optimum FSL performance. Use of a low
loss material, with styrofoam being optimum, to space the coil off
the ferrite also helps. (And of course using Litz wire for the
coil helps even more, if you can obtain/afford that.)
73,
Steve
On 1/29/2017 5:50 AM,
mont633@... [ultralightdx] wrote:
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Re: Hi from a new member with a question. (coil spacing off the ferrite)
Steve Ratzlaff
Hi Steven, Congrats on your first FSL success. Some of us have determined, back when FSLs were first heard about and lots of experimentation was going on, that the coil should be spaced about 1/4" to about 5/16" off the ferrite for optimum FSL performance. Use of a low loss material, with styrofoam being optimum, to space the coil off the ferrite also helps. (And of course using Litz wire for the coil helps even more, if you can obtain/afford that.) 73, Steve
On 1/29/2017 5:50 AM,
mont633@... [ultralightdx] wrote:
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Re: Hi from a new member with a question.
bill@...
I believe that the inductance of the coil is a function of the average
toggle quoted messageShow quoted text
permeability of what occupies the interior of the coil. I do not think that location within that area makes any difference, it is certainly not in the equations.
My question is, how importaint is the "air gap" between the outer of the
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Hi from a new member with a question.
steven
Hello,
I have just found your group and joined to day. I live in Scotland, UK. I found your group while googling about ferrite sleeve antennas, I am also a memeber of several other yahoo groups. I have made a few air cored loops or magnetic loop antennas and have had great results. Yesterday I made an approx 4" dia ferrite sleeve antenna with 30 off 10 mm x 140mm rods. I am pleased with the results, and checks last night showed that it is on a par with a 2 foot air cored loop I made. My question is, how importaint is the "air gap" between the outer of the ferrite rods and the coil or winding over the top of the ferrite rods. At present I have just wound approx 20 turns of insulated wire over the top of the duct tape that is holding the ferrite rods over the cardboard loop out of a roll of wide wasking tape. Results are good, but I was wondering if reception would improve any with the 5 mm or so air gap between the ferrite rods and the winding. Thanks very much in advance for any help or info. Regards, Steven. Scotland.
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Re: [IRCA] Oklahoma TP DX 1/26/17
Nick Hall-Patch
And, for your 518kHz, Mike, how about Navtex?
http://www.nws.noaa.gov/om/marine/navtex.htm http://www.dxinfocentre.com/navtex.htm (look at NAVAREA IV (North) as most likely? ) best wishes, Nick At 14:00 26-01-17, Mike Irizarry wrote: Expert DXers, I was listening this morning here in NW Chicago on 520Khz andNick Hall-Patch Victoria, BC Canada
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Oklahoma TP DX 1/26/17
bbwrwy
JOUB-774 was heard with poor signal fading in and out from 1135 until 1252 GMT. Also heard carrier signals from JOBB-828 and V7AB-1098.
Good DX. Richard Allen, near Perry OK USA, Skywave & FSL. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.
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The Bagpiper
Jordan Dobrikin <jjdobrikin@...>
---------- Forwarded message ---------- From: Jordan Dobrikin <jjdobrikin@...> Date: Tue, Jan 24, 2017 at 1:57 PM Subject: Re: The Bagpiper To: "poikaa3 ." <poikaarod@...> Hi Are Scot or Irish? My wife was Scot, a lowlander, no Tartan 73 de Jordan ve7jjd
On Tue, Jan 24, 2017 at 1:00 PM, poikaa3 . <poikaarod@...> wrote:
73 Jordan VE7JJD --
73 Jordan VE7JJD
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Re: Large Backyard MW Antennas
Thanks for your observations and comments, Todd.
<<< Gary might share his experiences with the relative performance of FSL and small loops versus larger antennas such as flags and beverages at more optimal coastal listening sites. Some interesting pictures have been posted of smaller portable flag antennas used at coastal DX monitoring sites. The recent Japanese / USA west coast DXpedition is one example. When different types of antennas are used on DXpeditions at the same listening site, the reception results and relative strengths indicate receiving system efficiency. Man-made noise interference is often lower at coastal listening sites compared to a home suburban backyard system. Line of sight to the horizon is desirable for all DX from LW to SHF, hence why coastal listening sites provide such impressive TP DX results when suitable signal propagation is open. >>>
During major ocean cliff DXpeditions there are usually multiple antenna and receiver combinations deployed, and of course there is a pretty long track record of the performance of the Ultralight + FSL combos against the Perseus-SDR + small broadband loop combos. The first major comparison of these was during the record-breaking July 2014 Rockwork 4 DXpedition, during which far more New Zealand stations were received (88 total) than ever before here on the North American west coast.
Because of the spectrum-capture capability Chuck's Perseus-SDR +15' x 15' broadband loop (assisted by an 11 dB preamp) received the vast majority of stations (87), but he admitted that the Tecsun PL-380 + 15" FSL combination could usually provide better signal quality on the lower MW frequency Kiwi stations. One weak (and rare) Kiwi station was received only on the ULR + FSL combination-- 585-Radio Ngati Porou. The single-optimized-frequency advantage of the tuned, High-Q FSL antennas makes them pretty tough competitors on the lower MW frequencies, signal-for-signal. Of course they can only tune one frequency at a time, though, so the total DX number of DX stations that they can receive is always much fewer than the small broadband loops can receive. One other related factor is that the $50 ULR's are nowhere near as sensitive and selective as the Perseus-SDR's, so the fact that the FSL antennas can make such a combo very competitive on the lower MW frequencies is a pretty astonishing fact. Once the FSL antennas are adapted for use with the Perseus-SDR and other communication receivers, such a combo would probably become the new "King of the Hill" on ocean cliffs, frequency-for-frequency.
73, Gary DeBock (in Puyallup, WA, USA)
-----Original Message----- From: toddemslie@... [ultralightdx] To: ultralightdx <ultralightdx@...> Sent: Thu, Jan 19, 2017 6:08 pm Subject: Re: [ultralightdx] Large Backyard MW Antennas Correct
Alex, all of the above is valid.
At
my home, a 120 ft wire backyard antenna + Icom R8500 is first checked to see if
trans-Pacific AM carriers are in from Hawaii, USA, or Mexico. Assuming the carriers
are either very weak or not present, it is not worthwhile switching on the
Tecsun ULR + 40" PVC loop. During some evenings around 2000 LT, the TP carriers are
above average in strength. This indicates it is worthwhile operating the ULR +
loop outdoors, and monitoring 1380, 1500, 1570, 1580 KHz TP channels. This is a
basic yes/no filter system for proceeding to the next level.
A
more ideal setup is a relatively large backyard flag antenna fixed towards the
USA. Higher gain antennas often produce lower noise levels by virtue of the
directional beamwidth attenuating noise from noise outside the antennas main
front forward lobe. Increased weak S/N translates to a longer DX window period. A Drake
series communications receiver and backyard low noise flag antenna should
outperform a small size FSL or loop + ULR, all other factors approximately equal. Given that
it is more convenient and cheaper to DX from home, for those with available land
space, some effort should be used to investigate higher relative gain receiving
systems for use in conjunction with smaller size and gain ULR
systems.
There
are situations where a ULR + FSL or small loop will outperform a large receiving
system back home. One example is New Zealand MW signals levels into eastern
Australia. NZ MW is considerably stronger on ULR portable systems when operation
is on or near a listening site facing the Pacific Ocean. My home location is some 15
miles inland from the coast, hence New Zealand, and TP signals are highly
reduced in signal strength, mainly due to terrain blockage.
Assuming
I was DXing from home on the west coast USA, weak carrier reception would be
first checked on a communications receiver before venturing outside to turn on a
ULR + loop / FSL at ~ 0600 LT early morning.
Gary
might share his experiences with the relative performance of FSL and small loops
versus larger antennas such as flags and beverages at more optimal coastal
listening sites. Some interesting pictures have been posted of smaller portable
flag antennas used at coastal DX monitoring sites. The recent Japanese / USA
west coast DXpedition is one example. When different types of antennas are used
on DXpeditions at the same listening site, the reception results and relative
strengths indicate receiving system efficiency. Man-made noise interference is
often lower at coastal listening sites compared to a home suburban backyard
system. Line of sight to the horizon is desirable for all DX from LW to SHF,
hence why coastal listening sites provide such impressive TP DX
results when suitable signal propagation is open.
Regards,
Todd
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Re: Large Backyard MW Antennas
Todd
<I
suppose that what you are asking (or proposing) is whether a home QTH with large
high performance antenna(s) and otherwise outstanding RX performance should be
used as a early warning system as a precursor for running down to the beach with
smaller antenna(s) and poor performance portable
receivers?>
Correct
Alex, all of the above is valid.
At
my home, a 120 ft wire backyard antenna + Icom R8500 is first checked to see if
trans-Pacific AM carriers are in from Hawaii, USA, or Mexico. Assuming the carriers
are either very weak or not present, it is not worthwhile switching on the
Tecsun ULR + 40" PVC loop. During some evenings around 2000 LT, the TP carriers are
above average in strength. This indicates it is worthwhile operating the ULR +
loop outdoors, and monitoring 1380, 1500, 1570, 1580 KHz TP channels. This is a
basic yes/no filter system for proceeding to the next level.
A
more ideal setup is a relatively large backyard flag antenna fixed towards the
USA. Higher gain antennas often produce lower noise levels by virtue of the
directional beamwidth attenuating noise from noise outside the antennas main
front forward lobe. Increased weak S/N translates to a longer DX window period. A Drake
series communications receiver and backyard low noise flag antenna should
outperform a small size FSL or loop + ULR, all other factors approximately equal. Given that
it is more convenient and cheaper to DX from home, for those with available land
space, some effort should be used to investigate higher relative gain receiving
systems for use in conjunction with smaller size and gain ULR
systems.
There
are situations where a ULR + FSL or small loop will outperform a large receiving
system back home. One example is New Zealand MW signals levels into eastern
Australia. NZ MW is considerably stronger on ULR portable systems when operation
is on or near a listening site facing the Pacific Ocean. My home location is some 15
miles inland from the coast, hence New Zealand, and TP signals are highly
reduced in signal strength, mainly due to terrain blockage.
Assuming
I was DXing from home on the west coast USA, weak carrier reception would be
first checked on a communications receiver before venturing outside to turn on a
ULR + loop / FSL at ~ 0600 LT early morning.
Gary
might share his experiences with the relative performance of FSL and small loops
versus larger antennas such as flags and beverages at more optimal coastal
listening sites. Some interesting pictures have been posted of smaller portable
flag antennas used at coastal DX monitoring sites. The recent Japanese / USA
west coast DXpedition is one example. When different types of antennas are used
on DXpeditions at the same listening site, the reception results and relative
strengths indicate receiving system efficiency. Man-made noise interference is
often lower at coastal listening sites compared to a home suburban backyard
system. Line of sight to the horizon is desirable for all DX from LW to SHF,
hence why coastal listening sites provide such impressive TP DX
results when suitable signal propagation is open.
Regards,
Todd
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Re: Large Backyard MW Antennas
Russ Edmunds
But one could always go to a beachfront motel, rent a room, and put up antennas on the beach, run cable in and DX in comfort. Russ Edmunds 15 mi NW Phila Grid FN20id <wb2bjh@...> AM: Modified Sony ICF2010's (4) barefoot w/whip FM: Yamaha T-80 & T-85, each w/ Conrad RDS Decoder; Onkyo T-450RDS; Tecsun PL-310 ( 4); modified Sony ICF2010's (3) w/APS9B @ 15'; modified Sony ICF2010 w/whip
On Thu, Jan 19, 2017 at 10:59 AM, winston376@... [ultralightdx] <ultralightdx@...> wrote:
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Re: Large Backyard MW Antennas
Alex P
Todd,
I suppose that what you are asking (or proposing?) is whether a home QTH with large high performance antenna(s) and otherwise outstanding RX performance should be used as a early warning system as a precursor for running down to the beach with smaller antenna(s) and poor performance portable receivers?? My thoughts are that I would prefer to be at my home QTH drinking my wine and eating warm quiche in my easy chair rather than crouching on a cold and wet bench at the beach with the wind blowing sand in my bologna sandwich. Let me know if I've misinterpreted your post. Alex
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Re: Large Backyard MW Antennas
Hi Todd,
<<< Perhaps some on this list might share positives and negatives with various types of outdoor MW antennas. While a Drake R8B, low noise RF preamplifier, and horizontal high elevation flag will often greatly excel ULR portable systems, they are nevertheless useful for early warning signal detection before MW signal propagation peaks to certain areas. It is often only during around the peak of an opening that signals are just barely strong enough for detection on a small ULR system. >>>
During major ocean cliff DXpeditions the combination of a 30-inch MW loopstick Sony ICF-2010 SSB spotting receiver (photo attached, and also posted at http://www.mediafire.com/view/6ct6za912sd2fu9/Hot-Rod-Paradise-02.jpg ) and the larger FSL antennas (15 inch and 17 inch) can usually detect the very weakest of transoceanic carrier signals, especially after the mega-FSL's provide their large inductive coupling boost to the modified Sony portable. Of course, whether or not this combination can dig out audio from such weak carriers is another matter entirely, and the Sony portable cannot measure the transmitted frequencies with the accuracy of a table receiver. The combination described above was used to detect a fairly good carrier on 1701 kHz during the July 2012 Cape Perpetua (Oregon) DXpedition, resulting in an English language recording (on a modified PL-380) that Australian DXers said was probably the Voice of Charity.
SSB reception is a huge advantage in detecting extremely weak MW signals, and SSB spotting receivers have been used with ULR's since the very beginning of the Ultralight radio boom in late 2007. The modified SSB spotting receivers (with enhanced MW loopsticks) are critical to ULR DXpedition success at the ocean cliff sites, and provide an ongoing assessment of changing propagation, transoceanic targets and unusual opportunities. Even at home sites the SSB spotting receivers can immediately assess whether transoceanic propagation is worth your DXing effort, or whether the band is in the clunker mode.
73, Gary DeBock (in Puyallup, WA, USA)
-----Original Message----- From: toddemslie@... [ultralightdx] To: ultralightdx Sent: Tue, Jan 17, 2017 4:24 pm Subject: [ultralightdx] Large Backyard MW Antennas While reading through all the ULR reports of weak
AM carrier reception from Korea, Japan, New Zealand, Australia, Polynesia, etc,
it makes sense for certain DXers to use a larger signal pickup system for early warning detection.
Before venturing outside with PVC and/or FSL antennas for use with ULR
portables, a large backyard antenna system such as a flag, sloper, EWE, or low noise
random wire antenna would usually detect weak carriers either audibly or
visually long before detection on ULR systems. A large higher gain backyard antenna system would first be
checked before venturing outside to confront good or otherwise weather
conditions. FFT spectrum analysers are capable of sub-audible carrier detection
long before the carrier can be audibly heard. When an accurate up to date
carrier list to XXX.XXX KHz accuracy, i.e. within 1 Hz, carriers such as 702 KHz ABC Sydney can often be discriminated from Asians or Europeans on the same 9 KHz channel. With this in mind, a 1 Hz precision frequency carrier list is being currently compiled for all MW receivable at my
location.
The most efficient MW antennas generally be need to
be relatively physically large, and mounted outside well away from the house RFI noise
field. Based on 160 metre (1.8 MHz) ham radio reception results, a rotatable
large horizontal flag mounted on a high tower is likely the ultimate compromise
for a backyard MW DX antenna. But a more practical antenna might be one or more
fixed vertical flag antennas. A DXer near the west U.S. coast might consider
installing a large outdoor flag antenna beaming towards
Japan/Korea/China.
The strong signal handling performance with a Drake R8 / R8A / R8B is usually sufficiently high for high gain signal input across the complete MW band, with no resulting internally generated spurious signal images from local stations. All ULRs would suffer from desensitisation and/or image/IMD when connected to high gain wideband antennas in suburban metro high signal areas.
Perhaps some on this list might share positives and
negatives with various types of outdoor MW antennas. While a Drake R8B, low
noise RF preamplifier, and horizontal high elevation flag will often greatly excel ULR portable systems,
they are nevertheless useful for early warning signal detection before MW signal
propagation peaks to certain areas. It is often only during around the peak of
an opening that signals are just barely strong enough for detection on a small
ULR system
Regards,
Todd
Sydney, AU
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Large Backyard MW Antennas
Todd
While reading through all the ULR reports of weak
AM carrier reception from Korea, Japan, New Zealand, Australia, Polynesia, etc,
it makes sense for certain DXers to use a larger signal pickup system for early warning detection.
Before venturing outside with PVC and/or FSL antennas for use with ULR
portables, a large backyard antenna system such as a flag, sloper, EWE, or low noise
random wire antenna would usually detect weak carriers either audibly or
visually long before detection on ULR systems. A large higher gain backyard antenna system would first be
checked before venturing outside to confront good or otherwise weather
conditions. FFT spectrum analysers are capable of sub-audible carrier detection
long before the carrier can be audibly heard. When an accurate up to date
carrier list to XXX.XXX KHz accuracy, i.e. within 1 Hz, carriers such as 702 KHz ABC Sydney can often be discriminated from Asians or Europeans on the same 9 KHz channel. With this in mind, a 1 Hz precision frequency carrier list is being currently compiled for all MW receivable at my
location. The most efficient MW antennas generally be need to
be relatively physically large, and mounted outside well away from the house RFI noise
field. Based on 160 metre (1.8 MHz) ham radio reception results, a rotatable
large horizontal flag mounted on a high tower is likely the ultimate compromise
for a backyard MW DX antenna. But a more practical antenna might be one or more
fixed vertical flag antennas. A DXer near the west U.S. coast might consider
installing a large outdoor flag antenna beaming towards
Japan/Korea/China. The strong signal handling performance with a Drake R8 / R8A / R8B is usually sufficiently high for high gain signal input across the complete MW band, with no resulting internally generated spurious signal images from local stations. All ULRs would suffer from desensitisation and/or image/IMD when connected to high gain wideband antennas in suburban metro high signal areas. Perhaps some on this list might share positives and
negatives with various types of outdoor MW antennas. While a Drake R8B, low
noise RF preamplifier, and horizontal high elevation flag will often greatly excel ULR portable systems,
they are nevertheless useful for early warning signal detection before MW signal
propagation peaks to certain areas. It is often only during around the peak of
an opening that signals are just barely strong enough for detection on a small
ULR system Regards, Todd
Sydney, AU
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Oklahoma TP DX 1/17/17
bbwrwy
1098 kHz V7AB? a weak carrier heard from 0621 GMT (Majuro sunset at 0638); barely audible man talking at 0703-0704.
1566 HLAZ with traces of a signal at 1326; barely audible from 1334 until close-down at 1344:30 (LSR at 1340). I was able to recognize Japanese language talk briefly. Richard Allen, near Perry OK USA, Skywave & FSL. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.
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Stealth Scanner Bag MK3 – January 2017
Paul Blundell
While this has been setup for radio scanning, the same ideas could be used for amateur handhelds and similar. Stealth Scanner Bag MK3 – January 2017
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