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Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Roy <roy.dyball@...>
 

Hi Guy

I noticed in your test that you had your radio tuned right at the bottom of the band (530Khz).

 I agree that with the same 81 turn sliding coil connected to my PL-380 that it showed an increase of about 20dbu and more importantly that the S/N had risen by some times up to 10-12db on the low frequency end of the band. These results are undeniable and improve the radio greatly

Did you get a chance to try stations at the top of the band? My coil started to drop off above 1200Khz and at the top of the band showed an increase in dbu of only about 7-10 and no increase in S/N level.

I also concur that my best results have been with coils wound in the centre of the rod. Extensive testing with different coils wound at the centre of the rod and different wire size and inductance has shown me that a value of inductance in the range 0f 330-350µH works the best over the entire band.

I found that a coil of 70 turn (110mm) 660 Litz wire wound at the centre performed the best overall and had the least amount of noise. When the varactor values are read from the Si4734 chip with it tuned to 1710 Khz it reports a value of around 10pf indicating the chip has not run out of capacitance at the top of the band. The inductance could be increased if you dont want to work the top end of the band.

The Welbrook range of gear looks like good gear and I hope your DX expedition goes well.

Cheers Roy.

--- In ultralightdx@..., Guy Atkins wrote:
>
> Hi Roy,
>
> I really appreciate the clear fashion in which you (and Scott) explain the
> SiLabs chip's operation! You are correct; I did not realize that the chip
> tunes for proper inductance after it detects a change of frequency; I
> thought it "senses" the inductance continuously, and displays any signal
> strength changes during the "refresh" cycle of the RSSI indicator.
>
> I'd forgotten about the maxim of best "Q" with a centered coil. After so
> many years of seeing stock loopsticks with factory coils positioned so far
> from center, I've not given it much thought. I like Scott's idea of starting
> coil winding right at the center, and seeing if there's any difference
> between a 330 uH and 550 uH coil.
>
> The purpose of the black arrow marker in my video was simply to show the
> positioning of the coil for which I had previously found to give the best
> reception. With that precise point in mind it was easier to see and hear the
> signal fall-off when the coil was shifted. However, I agree that by not
> retuning the receiver after each shift it becomes a moot point.
>
> Despite the flaws in the method, it still remains that I'm seeing a greater
> than 20 dB improvement over the stock loopstick, and that's excellent. If
> performance increases further with a coil at the rod's exact center, that
> will be even better.
>
> I'm knee-deep in finalizing Wellbrook arrays and QDFA phased array
> antennas plus other preparations for a coastal DXpedition later this month,
> so I won't be able to return to ULR radio experimentation for a while.
> However, I'm sure Gary and others will be able to follow up on your and
> Scott's suggestions soon. I look forward to reading about these experiments
> of others.
>
> 73,
>
> Guy Atkins
> Puyallup, WA USA
> http://fivebelow.squarespace.com
>
>
>
> On Tue, Feb 2, 2010 at 2:13 AM, ultralightdx@... wrote:
>
> > Ultralight DX
> >
> >
> >
>
>
> > 13e. Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick
> > Posted
> > by: "Roy" roy.dyball@...
> > roy.dyball@...?Subject=+Re%3A%20Guy%20Atkin%27s%20Independent%20Testing%20of%20PL-380%207%2E5%22%20Loopstick>
> > roy.dyball <http://profiles.yahoo.com/roy.dyball> Tue Feb 2, 2010 12:56 am
> > (PST)
> >
> >
> >
> > Hi Garry
> >
> > Looking at the video of the coil being moved indicates that the all that
> > is happening is that you are moving the coil away from a peak that has
> > already been established from a previous tuning operation that has set
> > the varactors capacitance to tune the loopstick at the black mark for
> > the coils inductance at that position on the rod. It appears to me that
> > the coil was originally tuned at the black mark then moved off peak
> > before the video started.
> >
> > You cannot expect the Si4734 to track while moving the coil because it
> > does not know the coil has moved and keeps the capacitance unchanged,
> > but you have changed the inductance by moving the coil and of course the
> > signal will rises and fall when you move the loopstick.
> >
> > Had the radio been retuned each time the coil was moved the Si4734 would
> > have returned its varactor capacitance for the new inductance brought
> > about by the movement and really the signal would not have changed by
> > much more than about 3dbu across the rod.
> >
> > The only time the Si4734 changes its capacitance to match the loopsticks
> > inductance is during a tuning operation and this was not done in the
> > video. The capacitance does not change automatically when you slide the
> > coil. The whole idea of the Si4734 is it is self aligning. And that is
> > why you must step off and step back on frequency every time you move the
> > loopstick.
> >
> > It would be very interesting to see the video redone showing the method
> > described above because every time the coil was moved and the frequency
> > retuned the audio and the signal levels (within about 3dbu) would have
> > come back up.
> >
> > We must understand how this chip works and use this chip as it is
> > designed and not copy old methods from completely different technology
> > without applying them to this new technology correctly.
> >
> > I think there has been a misunderstanding as to the correct operation of
> > how the Si4734 works and I now that criticism can be taken the wrong way
> > especially when someone has put a lot of work into their results and
> > presented them sincerely.
> >
> > I really believe that the video showing a peak signal on the rod is
> > incorrectly presented and had the radio been retuned between movements
> > it would have only shown how cleaver the Si4734 really is at realigning
> > itself and not a signal dropping off from an established peak.
> >
> > Cheers Roy.
> >
> > Create New Topic
> > |
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Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Gary DeBock
 

Hello Roy and Guy,
 
Thanks for your comments in this discussion, and thanks once again to Guy for his independent testing of my PL-380 7.5" loopstick design (and strong confirmation of the great AM sensitivity boost obtained with it, an aspect which seems to be overlooked in this marathon discussion, although it is the primary objective of the vast majority of our group).
 
Roy, your comments and suggestions are appreciated, as well as those form Scott. All of them will be tried here as time allows, since maximum loopstick performance is presumably our common objective, and all ideas are useful in this creative process.
 
Before delving into technical matters, however, there is one important point which I hope all of the group can understand and appreciate. Both Guy and I have used this PL-380 7.5" loopstick design to create an antenna which has already been extensively tested against the "champion" design of modified Ultralights-- the Eton E100 7.5" Slider model. This E100 Slider model has already proven highly successful as a stand-alone receiver in multiple DXpeditions, including Guy's vacation to Oregon last summer, Dr. Walt Salmaniw's travels in the South Pacific recently, and my multiple Grayland DXpeditions. After our optimal-sensitivity testing session on Saturday, Guy and I both conducted a "Shootout" between the same E100 Slider model he used in his Oregon DXpedition, and one of my new proof-tested PL-380 7.5" loopstick models. We checked stations across the MW spectrum, and we both found that the new PL-380 7.5" loopstick model could equal the performance of the E100 Slider in both selectivity AND sensitivity, without any need to tune a Slider coil. This is a tremendous improvement in transoceanic DXing convenience, especially during brief band openings (when time is critical). As such, since Guy and I have already been successful in making these new loopsticks with such impressive DXing performance, from our standpoint (as DXers, not software engineers) a great degree of success has certainly already been achieved. 
 
(Roy's comments pasted below)

"Looking at the video of the coil being moved indicates that the all that is happening is that you are moving the coil away from a peak that has already been established from a previous tuning operation that has set the varactors capacitance to tune the loopstick at the black mark for the coils inductance at that position on the rod. It appears to me that the coil was originally tuned at the black mark then moved off peak before the video started.

You cannot expect the Si4734 to track while moving the coil because it does not know the coil has moved and keeps the capacitance unchanged, but you have changed the inductance by moving the coil and of course the signal will rises and fall when you move the loopstick.

Had the radio been retuned each time the coil was moved the Si4734 would have returned its varactor capacitance for the new inductance brought about by the movement and really the signal would not have changed by much more than about 3dbu across the rod"

(my comments)

Roy,  I have run some further tests on the last remaining PL-380 7.5" test setup here, and you are  correct on this point.  Retuning the PL-380 (and starting with a new frequency each time the Slider coil is changed) is essential to understanding the Si4734 tuning operation, and how the varactor will compensate for frequency changes. As such, I think everyone is now much closer to agreement on how to optimize AM sensitivity in the final loopstick.

Following your suggestion, however, some interesting test results were obtained. As both you and Guy have noticed, the 554 uh coil inductance does not typically provide as great a sensitivity boost on the upper frequencies (X-band) as on the lower frequencies.  I set a Slider coil inductance of around 450 uh to investigate this, then retuned the PL-380 to 1680 kHz. In the 1680 kHz position, the 450 uh inductance did provide  significantly higher average RSSI and S/N readings (relative to a stock unit) than did the 554 uh inductance, but the average RSSI and S/N readings at the 530 kHz frequency were then significantly reduced. It was almost as if the greater signal boost obtained at the 450 uh inductance on 1680 kHz was gained at the loss of some signal boost at the 530 kHz frequency. As we proceed to test the operation of the PL-380 at varying coil inductances, it certainly seems that in the case of the 40/44 Litz wire Slider coil on the type 61 Amidon ferrite bar, some compromise in the final inductance will be necessary to equalize the sensitivity boost throughout the AM band.  Once such a "compromise inductance" is found, it would presumably be an easy matter to wind a coil of such inductance value in the center of the ferrite bar (as Scott suggests), and test whether this coil orientation would provide AM sensitivity superior to that of other coil locations. 

In any case, thanks again for your helpful suggestions , and especially for the continual atmosphere of discussing technical differences with mutual courtesy and respect. 

73 ,    Gary DeBock (in Puyallup, WA, USA)  

 

 

           In a message dated 2/2/2010 1:37:00 P.M. Pacific Standard Time, roy.dyball@... writes:

 

Hi Guy

I noticed in your test that you had your radio tuned right at the bottom of the band (530Khz).

 I agree that with the same 81 turn sliding coil connected to my PL-380 that it showed an increase of about 20dbu and more importantly that the S/N had risen by some times up to 10-12db on the low frequency end of the band. These results are undeniable and improve the radio greatly

Did you get a chance to try stations at the top of the band? My coil started to drop off above 1200Khz and at the top of the band showed an increase in dbu of only about 7-10 and no increase in S/N level.

I also concur that my best results have been with coils wound in the centre of the rod. Extensive testing with different coils wound at the centre of the rod and different wire size and inductance has shown me that a value of inductance in the range 0f 330-350µH works the best over the entire band.

I found that a coil of 70 turn (110mm) 660 Litz wire wound at the centre performed the best overall and had the least amount of noise. When the varactor values are read from the Si4734 chip with it tuned to 1710 Khz it reports a value of around 10pf indicating the chip has not run out of capacitance at the top of the band. The inductance could be increased if you dont want to work the top end of the band.

The Welbrook range of gear looks like good gear and I hope your DX expedition goes well.

Cheers Roy.

--- In ultralightdx@yahoogroups.com, Guy Atkins wrote:
>
> Hi Roy,
>
> I really appreciate the clear fashion in which you (and Scott) explain the
> SiLabs chip's operation! You are correct; I did not realize that the chip
> tunes for proper inductance after it detects a change of frequency; I
> thought it "senses" the inductance continuously, and displays any signal
> strength changes during the "refresh" cycle of the RSSI indicator.
>
> I'd forgotten about the maxim of best "Q" with a centered coil. After so
> many years of seeing stock loopsticks with factory coils positioned so far
> from center, I've not given it much thought. I like Scott's idea of starting
> coil winding right at the center, and seeing if there's any difference
> between a 330 uH and 550 uH coil.
>
> The purpose of the black arrow marker in my video was simply to show the
> positioning of the coil for which I had previously found to give the best
> reception. With that precise point in mind it was easier to see and hear the
> signal fall-off when the coil was shifted. However, I agree that by not
> retuning the receiver after each shift it becomes a moot point.
>
> Despite the flaws in the method, it still remains that I'm seeing a greater
> than 20 dB improvement over the stock loopstick, and that's excellent. If
> performance increases further with a coil at the rod's exact center, that
> will be even better.
>
> I'm knee-deep in finalizing Wellbrook arrays and QDFA phased array
> antennas plus other preparations for a coastal DXpedition later this month,
> so I won't be able to return to ULR radio experimentation for a while.
> However, I'm sure Gary and others will be able to follow up on your and
> Scott's suggestions soon. I look forward to reading about these experiments
> of others.
>
> 73,
>
> Guy Atkins
> Puyallup, WA USA
> http://fivebelow.squarespace.com
>
>
>
> On Tue, Feb 2, 2010 at 2:13 AM, ultralightdx@yahoogroups.com wrote:
>
> > Ultralight DX
> > yahoo.com/group/ultralightdx;_ylc=X3oDMTJlMmEydXJsBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDaGRyBHNsawNocGgEc3RpbWUDMTI2NTEwNTYxMA-->
> >
> >
>
>
> > 13e. Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick
> > yahoo.com/group/ultralightdx/message/7700;_ylc=X3oDMTJyOTFhazYzBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRtc2dJZAM3NzAwBHNlYwNkbXNnBHNsawN2bXNnBHN0aW1lAzEyNjUxMDU2MTA-> Posted
> > by: "Roy" roy.dyball@...
> > roy.dyball@...?Subject=+Re%3A%20Guy%20Atkin%27s%20Independent%20Testing%20of%20PL-380%207%2E5%22%20Loopstick>
> > roy.dyball yahoo.com/roy.dyball> Tue Feb 2, 2010 12:56 am
> > (PST)
> >
> >
> >
> > Hi Garry
> >
> > Looking at the video of the coil being moved indicates that the all that
> > is happening is that you are moving the coil away from a peak that has
> > already been established from a previous tuning operation that has set
> > the varactors capacitance to tune the loopstick at the black mark for
> > the coils inductance at that position on the rod. It appears to me that
> > the coil was originally tuned at the black mark then moved off peak
> > before the video started.
> >
> > You cannot expect the Si4734 to track while moving the coil because it
> > does not know the coil has moved and keeps the capacitance unchanged,
> > but you have changed the inductance by moving the coil and of course the
> > signal will rises and fall when you move the loopstick.
> >
> > Had the radio been retuned each time the coil was moved the Si4734 would
> > have returned its varactor capacitance for the new inductance brought
> > about by the movement and really the signal would not have changed by
> > much more than about 3dbu across the rod.
> >
> > The only time the Si4734 changes its capacitance to match the loopsticks
> > inductance is during a tuning operation and this was not done in the
> > video. The capacitance does not change automatically when you slide the
> > coil. The whole idea of the Si4734 is it is self aligning. And that is
> > why you must step off and step back on frequency every time you move the
> > loopstick.
> >
> > It would be very interesting to see the video redone showing the method
> > described above because every time the coil was moved and the frequency
> > retuned the audio and the signal levels (within about 3dbu) would have
> > come back up.
> >
> > We must understand how this chip works and use this chip as it is
> > designed and not copy old methods from completely different technology
> > without applying them to this new technology correctly.
> >
> > I think there has been a misunderstanding as to the correct operation of
> > how the Si4734 works and I now that criticism can be taken the wrong way
> > especially when someone has put a lot of work into their results and
> > presented them sincerely.
> >
> > I really believe that the video showing a peak signal on the rod is
> > incorrectly presented and had the radio been retuned between movements
> > it would have only shown how cleaver the Si4734 really is at realigning
> > itself and not a signal dropping off from an established peak.
> >
> > Cheers Roy.
> >
> > Create New Topic
> > yahoo.com/group/ultralightdx/post;_ylc=X3oDMTJmOGo5MnNzBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNudHBjBHN0aW1lAzEyNjUxMDU2MTA->|
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Re: Si4734 Hardware and Software Guides

gratiscomputer <gratiscomputer@...>
 

Roy schreef:

Marc

Here is a link to the Delphi code it is at the bottom of the page

http://www.elexs.de/SI4735c.html <http://www.elexs.de/SI4735c.html>

Roy

Roy,

Here is the link on how to let freepascal compile/import Delphi code:
http://wiki.freepascal.org/Delphi

Marc


Re: Si4734 Hardware and Software Guides

Roy <roy.dyball@...>
 

Marc

Here is a link to the Delphi code it is at the bottom of the page

http://www.elexs.de/SI4735c.html

Roy


--- In ultralightdx@..., gratiscomputer wrote:
>
> Roy schreef:
> >
> >
> > Hi Marc
> >
> > Yes I came across that site. They had written their code in VB6 and
> > were using the I2C interface to control the chip. They openly admitted
> > it did not work properly and someone had
> >
> I threw away my history in firefox, which was a stupid idea... Do you
> have the site??
>
> Delphi is Pascal code and is much clearer than all those VB/C++/C# samples..
> http://freepascal.org will supply a pascal compiler for all platforms...
>
>
> Marc
>


Re: OOPS! Forgot Jim Kearman!

jim_kr1s <jkearman@...>
 

Thanks again for the nice certificate, John! It took me a month to get to 15 countries, and the next 5 took another month. There is an awful lot of interference from Cuban stations here, plus a fair number of Florida stations. Some nights the path into Europe just never opens from down here. The farthest north I've been able to copy is the UK, only about 4300 miles. But copying the Mideast, >7000 miles away, on a radio that fits in my shirt pocket is lots of fun, even if the programming is mostly boring (not R Farda, though -- love the music!).

Looking toward South America, Cuba, with 191 AM stations, is right in the way. Some night I ought to take the radio outside and let the condo buildings act like a screen. Maybe that will enhance reception to the east and northeast. I'm up to 21 now, and there are a few seemingly easy Europeans left. Maybe this month I'll hit 25.

About half of the 20 were logged with a barefoot G8. I got a Terk antenna the same day as the PL-380 arrived just before Christmas, and used that for a few more. I'm sure they could have been logged barefoot but I wasn't thinking about the certificate. Had the Terk, why not use it? Then the PL-380 got the irreversible internal antenna mod, so it's Unlimited all the way, now. Guess I could use the PL-380 as a spotter and log them as Barefoot with the G8, but that's too much like work. Could try hooking up the big air loop I made for my homemade receiver, but haven't needed it so far. Sooner or later they all fade up to audibility. Also, I like being able to DX while walking around the house. The public beaches here close at sunset. Our county commissioners are obviously not MW DXers! I live a couple of miles inland.

One thing about logging foreign countries is that it's reduced my interest in logging domestics. I've become addicted to Heterodyne Hunting. :)

73,

Jim, KR1S
http://qrp.kearman.com/ 


Re: Si4734 Hardware and Software Guides

sdwillingham
 

Roy,

A clarification: the code in the reference design I linked to
is actually operating the chip in 3-wire mode. It nicely makes
use of the MCU's SPI interface hardware, but the incoming and
outgoing serial data lines are actually connected together with
a 1 kohm resistor (see the schematic in the app note).

I actually used a version of that code example in the first
version of my interface. That said, I'm back to bit-banging
with my current software.

Yesterday, one of these arrived at my house from Mouser:

http://www.silabs.com/Support%20Documents/TechnicalDocs/ToolStick_F321_DC_UG.pdf

It's quite a lot bigger than my present prototype, but should be
easier to work with in terms of solder points, etc. Last night
I determined that if I cut off the bottom third of the board
(where the potentiometer and switch are), I will be able to fit
the remainder inside my PL-380. (These Tecsuns are remarkable
in their packaging design -- very little wasted space and yet
very easy to dis- and re-assemble.) The PL-380's built-in USB
connector will make this a very stealth modification!

-Scott-

--- In ultralightdx@..., "Roy" <roy.dyball@...> wrote:

Because the Tecsun uses the 3 wire interface I feel it is best to stick
with it while they use it because I can unhook my interface, and as soon
as I switch the local MCU control lines back in it takes over without a
fuss and you can still use any changes you have made until power down
while using the radio normally.

I am really leaning toward using an MCU like you are doing and am
looking forward to seeing your final results. I noticed you have posted
more pictures and your radio with interface looks good now it is back
together.


Re: conditions last night

jim_kr1s <jkearman@...>
 


--- In ultralightdx@..., Allen Willie >
>
> Last night here in the North Atlantic produced a TA opening which was later than usual here ( about 1:30 AM Local 5:00 UTC ) Was hoping to ride the wave longer but the sandman took over .

Allen,

Strong coffee! :)  Good results there. The aurora is really kicking up, and the geomagnetic field is disturbed today.

http://sec.noaa.gov/pmap/pmapN.html


http://geomag.nrcan.gc.ca/common_apps/ssp-1-eng.php

As you're so much farther north than me I'd be interested in how things fare tonight.

Other sources of propagation info at "Propagation" tab here: http://kr1s.kearman.com/

73,

Jim, KR1S
http://qrp.kearman.com/ 


Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Guy Atkins
 



Hi Roy,
 
I really appreciate the clear fashion in which you (and Scott) explain the SiLabs chip's operation! You are correct; I did not realize that the chip tunes for proper inductance after it detects a change of frequency; I thought it "senses" the inductance continuously, and displays any signal strength changes during the "refresh" cycle of the RSSI indicator.
 
I'd forgotten about the maxim of best "Q" with a centered coil. After so many years of seeing stock loopsticks with factory coils positioned so far from center, I've not given it much thought. I like Scott's idea of starting coil winding right at the center, and seeing if there's any difference between a 330 uH and 550 uH coil.
 
The purpose of the black arrow marker in my video was simply to show the positioning of the coil for which I had previously found to give the best reception. With that precise point in mind it was easier to see and hear the signal fall-off when the coil was shifted. However, I agree that by not retuning the receiver after each shift it becomes a moot point.
 
Despite the flaws in the method, it still remains that I'm seeing a greater than 20 dB improvement over the stock loopstick, and that's excellent. If performance increases further with a coil at the rod's exact center, that will be even better.
 
I'm knee-deep in finalizing Wellbrook arrays and QDFA phased array antennas plus other preparations for a coastal DXpedition later this month, so I won't be able to return to ULR radio experimentation for a while. However, I'm sure Gary and others will be able to follow up on your and Scott's suggestions soon. I look forward to reading about these experiments of others.
 
73,
 
Guy Atkins
Puyallup, WA USA
 
 
 
On Tue, Feb 2, 2010 at 2:13 AM, <ultralightdx@...> wrote:

 
13e.

Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Posted by: "Roy" roy.dyball@...   roy.dyball

Tue Feb 2, 2010 12:56 am (PST)




Hi Garry

Looking at the video of the coil being moved indicates that the all that
is happening is that you are moving the coil away from a peak that has
already been established from a previous tuning operation that has set
the varactors capacitance to tune the loopstick at the black mark for
the coils inductance at that position on the rod. It appears to me that
the coil was originally tuned at the black mark then moved off peak
before the video started.

You cannot expect the Si4734 to track while moving the coil because it
does not know the coil has moved and keeps the capacitance unchanged,
but you have changed the inductance by moving the coil and of course the
signal will rises and fall when you move the loopstick.

Had the radio been retuned each time the coil was moved the Si4734 would
have returned its varactor capacitance for the new inductance brought
about by the movement and really the signal would not have changed by
much more than about 3dbu across the rod.

The only time the Si4734 changes its capacitance to match the loopsticks
inductance is during a tuning operation and this was not done in the
video. The capacitance does not change automatically when you slide the
coil. The whole idea of the Si4734 is it is self aligning. And that is
why you must step off and step back on frequency every time you move the
loopstick.

It would be very interesting to see the video redone showing the method
described above because every time the coil was moved and the frequency
retuned the audio and the signal levels (within about 3dbu) would have
come back up.

We must understand how this chip works and use this chip as it is
designed and not copy old methods from completely different technology
without applying them to this new technology correctly.

I think there has been a misunderstanding as to the correct operation of
how the Si4734 works and I now that criticism can be taken the wrong way
especially when someone has put a lot of work into their results and
presented them sincerely.

I really believe that the video showing a peak signal on the rod is
incorrectly presented and had the radio been retuned between movements
it would have only shown how cleaver the Si4734 really is at realigning
itself and not a signal dropping off from an established peak.

Cheers Roy.



conditions last night

Allen Willie
 

 
 
Hi Guys,
 
Last night here in the North Atlantic produced a TA opening which was later than usual here ( about 1:30 AM Local 5:00 UTC ) Was hoping to ride the wave longer but the sandman took over .
 
1476 khz -  Euskadi Irratia , Biribilondo Spain  5:32 UTC 2/2/10 - News by man  in Basque or Spanish  (strongest signal I've ever heard from this one )
 
 
Other logs earlier in the evening
 
1150 khz - CHGM - Gaspe, Quebec  00:27 UTC 2/2/10 w/ french talk and many Country music tunes in English and french  (sounded like a local )
 
 720 khz - KNR - Simmutaq, Greenland   00:50 UTC 2/2/10 w/ musical selections and woman reading in Danish or Greenlandic (Great signal from this one tonight )
 
 
Good DX to All
 
Allen Willie
St. John's, Newfoundland  37:47N  52:45W
SRF-39 FP barefoot
 
 


Yahoo! Canada Toolbar : Search from anywhere on the web and bookmark your favourite sites. Download it now!


Re: I received my PL-380 today but don´t know

www-clorofila-up-to@...
 

Hi Neil,

Thanks for your return.

The merit goes to Jim and Gary because the too important photos that clarify once and for all any doubt about the identification of PL-380´s newest version.

Milton

Brasil

 

 

Re: [ultralightdx] Re: I received my PL-380 today but don´t know

Posted by: "Neil Findlay" neil.findlay52@... neil.findlay52

Tue Feb 2, 2010 4:53 am (PST)



Thanks

I had not found till I saw your Photograph

Looked an still could not see it -- opened other end that was still taped up and there it was

So mine is a 2009 version 1

Thanks again

Neil Findlay

 


Traverse City, MI Loggings, All Times UTC

Antonios Kekalos <akekalos@...>
 

2.2.10, 0529, am 1660, WQLR, Kalamazoo, MI, 175mi/281km, Sony SRF-M37V (The Fan)
2.2.10, 1350, am 1680, WPRR, Grand Rapids, MI, 127mi/204km, Sony SRF-M37V (Public Reality Radio)

--
Tony Kekalos
Traverse City, MI
SWLR-RN072
EN74es



Re: Si4734 Hardware and Software Guides

gratiscomputer <gratiscomputer@...>
 

Roy schreef:

Hi Marc

Yes I came across that site. They had written their code in VB6 and were using the I2C interface to control the chip. They openly admitted it did not work properly and someone had
I threw away my history in firefox, which was a stupid idea... Do you have the site??

Delphi is Pascal code and is much clearer than all those VB/C++/C# samples..
http://freepascal.org will supply a pascal compiler for all platforms...


Marc


Re: I received my PL-380 today but don´t know if it´s the late...

neil.findlay52
 

Thanks
 
I had not found till I saw your Photograph
 
Looked an still could not see it -- opened other end that was still taped up and there it was

So mine is a 2009 version 1
 
Thanks again
 
Neil Findlay
 


From: jim_kr1s <jkearman@...>
To: ultralightdx@...
Sent: Tue, 2 February, 2010 1:02:36 AM
Subject: [ultralightdx] Re: I received my PL-380 today but don´t know if it´s the late...

 


--- In ultralightdx@ yahoogroups. com, "Silvio" wrote:

> According Jim´s answer (which also grateful for the answer) I sniffed that he he did not know about the details of this so relevante label with this inscription.

Hi, Milton,

My eyes are going. I found the numbers on the end of the flap. I put a photo with a ring around the version number in the Photos section of our Yahoo site, in an album titled "PL-380 Version." This link to it might work:

http://groups. yahoo.com/ group/ultralight dx/photos/ album/1244091616 /pic/list

73,

Jim, KR1S
http://qrp.kearman. com/ 



Yahoo!7: Catch-up on your favourite Channel 7 TV shows easily, legally, and for free at PLUS7. Check it out.


Re: Si4734 Hardware and Software Guides

Roy <roy.dyball@...>
 

Hi Marc

Yes I came across that site. They had written their code in VB6 and were using the I2C interface to control the chip. They openly admitted it did not work properly and someone had rewritten the program using Delphi which is what they are using now.

Cheers Roy.   

--- In ultralightdx@..., gratiscomputer wrote:
>
> Roy schreef:
> >
> >
> > Hi Scott
> >
> > Thank you for the link to the sample C code and the explanation. All
> > my code is written in VB.NET 2008. I have many years experience with
> > it from my previous business dealings before I retired and the program
> > was going before I thought too much about it. I have got the 3 wire
> > interface running really well and the 9 bit data word was a real
> > challenge especially in VB.NET, I think the hardest part was getting
> > the half clock cycle delay correct during the bus turn around.
> >
>
> Strange, but I think I saw some source code on the german site modul-bus
> ag (or so), where they sell a silabs chip on a usb-bridge.
>
> Marc
>


Re: I received my PL-380 today but don´t know if it´s the late...

Silvio <www-clorofila-up-to@...>
 

Hi Jim, Hi Gary !

Thanks both for the highly useful and enlightening photos and explantions about soft mute & SW stability !

Unfortunately my Pl-380 is old version.

Because my english is basic (many times with google´s help) i did not understand the meaning of the word "flap" and only with the box´s flap photo i could do it.

So since the soft mute did not change, I'll give it time before making a possible exchange or acquisition of a new version.

I am very grateful for clarification and follow my wishes of great 73's for everyone.

Maybe my question is that of many people because with respect to SW, I am thinking about creating a port for an external antenna to SW to pull a wire from the battery negative and another from telescopic antenna. I did this with the Tecsun R9012 that I had and the improvement was remarkable. I think there would be no problem in the case of PL-380. Although i'm more focused on Dxer in OM, i thik to do this procedure.

Milton
Brasil


In ultralightdx@..., "jim_kr1s" <jkearman@...> wrote:


--- In ultralightdx@..., "Silvio" <www-clorofila-up-to@>
wrote:

According Jim´s answer (which also grateful for the answer) I
sniffed that he he did not know about the details of this so relevante
label with this inscription.

Hi, Milton,

My eyes are going. I found the numbers on the end of the flap. I put a
photo with a ring around the version number in the Photos section of our
Yahoo site, in an album titled "PL-380 Version." This link to it might
work:

http://groups.yahoo.com/group/ultralightdx/photos/album/1244091616/pic/l\;
ist
<http://groups.yahoo.com/group/ultralightdx/photos/album/1244091616/pic/\;
list>

73,

Jim, KR1S
http://qrp.kearman.com/ <http://qrp.kearman.com/>
Re: [ultralightdx] Re: I received my PL-380 today but don´t know
Posted by: "D1028Gary@..." D1028Gary@... dxergary
Mon Feb 1, 2010 5:35 pm (PST)


Hi Milton,

Thank you for your kind comments, which are much appreciated.

My earlier photo of the Tecsun PL-380 model shipping boxes was not so
clear, so here is a better one. You can easily see the writing "2009.9 VER.2"
and "2009.9 VER.1" on the shipping box flaps in the photo below, which can
help any DXer determine whether or not the model is a "new version" or old
version" PL-380. This same photo is posted at
_http://www.mediafire.com/?nimoyajwkzj_ (http://www.mediafire.com/?nimoyajwkzj) , for those who cannot
receive the photo in their email.

Regarding the soft-mute issue, Milton, I have tested both the "new version"
and "old version" PL-380 models by tuning 1 kHz up or down (as Scott has
recommended), but I cannot detect any difference in the soft-mute function.
I think that the soft-mute function is set at the same level on both of the
PL-380 versions, but this level is significantly lower than on the PL-310,
D96L or other Si4734 models.

Milton, the SW band on the PL-380 is usually stable on all models, both new
and old version. When I was drafting the PL-380 review one of my two
review models had a defective SW section with an intermittent oscillation
problem, but this was only a problem in one out of twelve PL-380 models so far,
so it seems that this was just a rare issue. Seven other "old version"
PL-380 models have been fine on the SW band.
***


Re: Si4734 Hardware and Software Guides

gratiscomputer <gratiscomputer@...>
 

Roy schreef:

Hi Scott

Thank you for the link to the sample C code and the explanation. All my code is written in VB.NET 2008. I have many years experience with it from my previous business dealings before I retired and the program was going before I thought too much about it. I have got the 3 wire interface running really well and the 9 bit data word was a real challenge especially in VB.NET, I think the hardest part was getting the half clock cycle delay correct during the bus turn around.
Strange, but I think I saw some source code on the german site modul-bus ag (or so), where they sell a silabs chip on a usb-bridge.

Marc


Re: Si4734 Hardware and Software Guides

Roy <roy.dyball@...>
 

Hi Phil

I would gladly do that for you but my G8 with the interface has the Si4734 removed at the moment. I will be able to do it toward the end of the week when the new chip arrives and I have installed it.

When you tune a SW frequency you change the 0 high and low byte capacitance values signifying automatic tunning at MW frequencies, to a 1 in the low byte and a 0 in the high byte capacitance value signifying SW. I can't remember what it comes back with for SW frequencies but I will let you know as soon as it is running again.

Roy.

--- In ultralightdx@..., "just_rtfm" wrote:
>
>
>
> Roy, thanks for your informative post! if you have time: tune your G8 to 5 MHz via the radio and then poll status via your USB interface, what is the capacitor value? how about at 10 MHz? 20 MHz?
>
> Scott, thanks for the ZIP... lots of great info in there.
>
> regards,
> phil :)
>


Re: Si4734 Hardware and Software Guides

Roy <roy.dyball@...>
 

Hi Scott

Thank you for the link to the sample C code and the explanation. All my code is written in VB.NET 2008. I have many years experience with it from my previous business dealings before I retired and the program was going before I thought too much about it. I have got the 3 wire interface running really well and the 9 bit data word was a real challenge especially in VB.NET, I think the hardest part was getting the half clock cycle delay correct during the bus turn around.

Because the Tecsun uses the 3 wire interface I feel it is best to stick with it while they use it because I can unhook my interface, and as soon as I switch the local MCU control lines back in it takes over without a fuss and you can still use any changes you have made until power down while using the radio normally.

I am really leaning toward using an MCU like you are doing and am looking forward to seeing your final results. I noticed you have posted more pictures and your radio with interface looks good now it is back together.

Cheers Roy.

--- In ultralightdx@..., "sdwillingham" wrote:
>
>
>
>
> Roy,
>
> The 9-bit control word is a bit of a pain, but although it is not
> obvious, it is not too hard to use a standard 8-bit SPI-type
> interface to communicate with the Si4734. The technique is used
> in this software:
>
> http://www.silabs.com/Support%20Documents/Software/AN264SW.zip
>
> (See the CONTROL_WRITE and CONTROL_READ macros in file
> F320_Si470x_Interface.h. Note, this code is for the Si470x parts,
> but works the same for Si473x if you change the chip-address to
> 0xA0 instead of 0x60.)
>
> The basic idea is to do a 2-byte read or write by packaging the
> 25-bit command+response or command+data in four 8-bit transactions.
> (While manually banging the SENB signal before and after the
> 32-bits.) The first 25 bits are as documented for the part. The
> last 7 bits just hang on as partial extra response or data. When
> SENB is driven high, the last partial transaction is aborted and
> the control interface state-machine is reset for a new transaction.
>
> Perhaps you can simplify your interface with this technique.
>
> Cheers,
> Scott
>
> --- In ultralightdx@..., "Roy" roy.dyball@ wrote:
> > The 3 wire (SDIO SCLK SEN) control interface opened up a big can of
> > worms because it uses a non standard nine bit control word. I then
> > discovered I could use the advanced bit banging functions of the FTDI
> > chip to construct a non standard nine bit word and get my I/O routines
> > running fast enough to produce good results. By this time it was clear
> > to me that RS-232 would not do the job.
>


Re: Si4734 Hardware and Software Guides

just_rtfm
 

Roy, thanks for your informative post! if you have time: tune your G8 to 5 MHz via the radio and then poll status via your USB interface, what is the capacitor value? how about at 10 MHz? 20 MHz?

Scott, thanks for the ZIP... lots of great info in there.

regards,
phil :)


Re: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Roy <roy.dyball@...>
 

Hi Garry

Looking at the video of the coil being moved indicates that the all that is happening is that you are moving the coil away from a peak that has already been established from a previous tuning operation that has set the varactors capacitance to tune the loopstick at the black mark for the coils inductance at that position on the rod. It appears to me that the coil was originally tuned at the black mark then moved off peak before the video started.

You cannot expect the Si4734 to track while moving the coil because it does not know the coil has moved and keeps the capacitance unchanged, but you have changed the inductance by moving the coil and of course the signal will rises and fall when you move the loopstick.

Had the radio been retuned each time the coil was moved the Si4734 would have returned its varactor capacitance for the new inductance brought about by the movement and really the signal would not have changed by much more than about 3dbu across the rod.

The only time the Si4734 changes its capacitance to match the loopsticks inductance is during a tuning operation and this was not done in the video. The capacitance does not change automatically when you slide the coil. The whole idea of the Si4734 is it is self aligning. And that is why you must step off and step back on frequency every time you move the loopstick.

It would be very interesting to see the video redone showing the method described above because every time the coil was moved and the frequency retuned the audio and the signal levels (within about 3dbu) would have come back up.

We must understand how this chip works and use this chip as it is designed and not copy old methods from completely different technology without applying them to this new technology correctly.

I think there has been a misunderstanding as to the correct operation of how the Si4734 works and I now that criticism can be taken the wrong way especially when someone has put a lot of work into their results and presented them sincerely. 

I really believe that the video showing a peak signal on the rod is incorrectly presented and had the radio been retuned between movements it would have only shown how cleaver the Si4734 really is at realigning itself and not a signal dropping off from an established peak.

Cheers Roy. 

 


--- In ultralightdx@..., D1028Gary@... wrote:
>
> Hello All,
>
> This is forwarded from Guy Atkins, who apparently had a problem getting
> this message posted to the Ultralightdx Yahoo site:
>
>
>
>
> .
>
>
> ---------- Forwarded message ----------
> From: Guy Atkins <_dx@..._ (mailto:dx@...) >
> Date: Mon, Feb 1, 2010 at 4:56 PM
> Subject: Modding the Tecsun PL-380 with an External Ferrite Antenna - My
> Experience
> To: _ultralightdx@... (mailto:ultralightdx@...)
>
>
> I've followed some of the recent discussion about modifying the PL-380
> with the Amidon type 61, 7.5" ferrite rod that is commonly used with the
> hotrodded Eton E100 receivers. Having modified Kchibo D96Ls and Eton E100s with
> this useful Amidon item, I decided that it was time to try my hand at the
> Tecsun PL-380.
>
>
> I wasn't sure what to expect regarding the optimum coil inductance and
> position of the coil on the ferrite, since there's been a good amount of
> debate on this topic. Gary DeBock claims an inductance around 554 uH is the best
> for all MW frequencies, and that there's a "sweet spot" on the rod where
> an 81 turn coil of 40/44 Litz wire provides this inductance, giving the
> strongest signals across the band with this fixed position coil.
>
>
> The SiLab Si4734 chip's datasheet indicates an acceptable 180-450 uH
> inductance range for the antenna, and the chip tunes a varactor capacitor for
> best performance on each MW frequency (resonating the LC circuit)... no
> manual adjustments at the factory are needed. For the ULR experimenter this
> means there should be NO "best" position (sweet spot) of a coil on the external
> Amidon ferrite rod, as long as the inductance is within 180-450 uH.
>
>
> I dove into the disassembly of my PL-380, very curious as to what I would
> find gives the best signal gain with an Amidon rod modified receiver. Maybe
> there's be no difference 180 to 450 uH, just as SiLabs' data implies.
>
>
> I removed the small, flat ferrite antenna from the PL-380 and found it
> measured 239 uH, clearly within the specified range.
>
>
> An 81 turn Litz wire coil (the recommended 40/44 style) with Amidon 7.5"
> type 61 rod was tried next, mounted externally with the "piece of a
> carpenters level" trick that Gary pioneered as a simple frame to support a slider
> coil antenna.
>
>
> It was quickly evident that Gary is correct--there *is* a "best"
> inductance for the PL-380, and it is far outside the range given in the SiLabs
> chip's documentation. I listened to low, mid, and high-band MW stations for an
> audible peak and kept a close watch on the RSSI signal numbers on the
> radio's display while sliding the coil left and right (and taking average
> readings over a minute or so). With the coil positioned at the ends, signals were
> barely audible, but rose quickly to maximum levels at a location about
> 1-3/4 inches from the end of the rod to the first edge of the coil. Beyond that
> distance, the RSSI values started dropping (but not as quickly as they
> rose within the 1-3/4 inches from the end of the rod.) No matter what MW
> frequency I tuned, there was one small place on the Amidon rod where signals
> were strongest.
>
>
> I taped the coil in this "best" position, disconnected the antenna leads
> from the receiver, and measured the resulting value. It was 533 uH! This
> number is very close to Gary's claimed 554 uH optimum, and obviously beyond
> the 450 uH upper limit stated by SiLabs for an AM broadcast antenna. With the
> coil moved toward the end of the Amidon rod, I measured around 300 uH (all
> but the strongest signals were inaudible with 300 uH inductance on the
> Amidon rod).
>
>
> See below for a short video (1 Mb WMV file) I made of the peaking of my
> local TIS station on 530 kHz using this PL-380 setup. It's a bit blurry, but
> the RSSI and SNR numbers can be seen changing. I placed a triangle of black
> tape on the support frame pointing to the "optimum" position of the left
> edge of the coil to help you observe and hear the signal changes left &
> right of the best spot. It is this position marked with the black arrow that
> results in a 533 uH inductance on my setup.
>
>
> _http://www.mediafire.com/?zdjhxmmmtyz_
> (http://www.mediafire.com/?zdjhxmmmtyz)
>
>
> Here are some photos and captions of different steps of this PL-380
> project: _http://tinyurl.com/ycajpex_ (http://tinyurl.com/ycajpex) Click on the
> thumbnail images and use the PicasaWeb magnifying glass tool for up-close
> views.
>
>
> This modified PL-380 is as sensitive as any slider coil E100 hotrod ULR
> radio I've built and used. I look forward to snagging some TP DX with this
> little wonder! The multiple DSP bandwidths are as useful as those on the
> Kchibo D96L, but the minimal soft mute is an excellent benefit of the PL-380. I
> also appreciate the easy frequency entry and the overall build quality of
> the Tecsun receiver.
>
>
> So what do we conclude about the "correct" inductance for the PL-380
> antenna? First of all, Gary is correct--an inductance of approximately 530-550
> uH when used with the 7.5", 61 type ferrite material from Amidon and 40/44
> Litz wire clearly provides the most sensitivity. Why this is well out of the
> SiLab-recommended range of inductance, I have no idea. Maybe it involves
> the physical size and ferrite mix of the rod, along with the Litz coil
> parameters, although this contradicts what others have said about the Si4734
> chip automatically matching any 180-450 uH coil, period.
>
>
> Whatever yet-to-be-discovered reason for the modded PL-380's behavior, I'm
> happy that fellow DXer and Puyallup, WA resident Gary DeBock has shared
> his discoveries freely with the rest of us. I'm sure he knew he'd get some
> "heat" for his unorthodox claim about modding the PL-380. I commend him for
> not keeping quiet, and for taking a risk to publicize his findings.
>
>
> As a reminder, Gary's article that details this modification to the PL-380
> is found here:
> _http://www.dxer.ca/file-area/doc_details/289-supercharging-the-tecsun-pl-38
> 0_
> (http://www.dxer.ca/file-area/doc_details/289-supercharging-the-tecsun-pl-380)
>
>
> I'm sure others will continue to debate theory vs. hands-on results with
> the PL-380 receiver, but if you'll excuse me I have some DX to snag with
> this little hotrod from Tecsun...
>
>
> 73,
>
>
> Guy Atkins
> Puyallup, WA
> _http://fivebelow.squarespace.com_ (http://fivebelow.squarespace.com/)
>