Date   

Re: Measuring PL-380 Soft-Mute

sdwillingham
 

Jim,

My idea is to off-tune from the carrier, so the chip "thinks"
the SNR is constantly zero. Unless the chip finds another
carrier at the off-tuned frequency, this should engage
the soft-mute operation in a constant fashion. Constant
soft-mute attenuation should not exaggerate the beating of
two competing carriers.

I haven't checked this out extensively, so there might be
some other practical limitation I'm not thinking of.

-Scott-

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


--- In ultralightdx@..., "sdwillingham" <sdwillingham@>
wrote:


This suggests one way to defeat the effect: just off-tune
from the carrier by 1 kHz, which engages the soft-mute.
Then turn your volume knob up by 2-clicks (PL-380) or
4-clicks (PL-300). As long as you can live with the offset
filtering, this should get rid of the pumping effect. Since
you are already dealing with low-SNR signals, this technique
should not further degrade reception.
Scott,

This is true if there is only one steady signal, or at least no phase
difference between multiple signals. When two signals on the same
frequency are out of phase, when they cancel each other, the drop in
volume is quite a bit more noticeable on the G8/PL-300wt than on the
PL-380, even when tuned to the carrier frequency.

You can raise the audio floor by turning up the volume, but then the
audio ceiling is increased by the same amount, so the effect is
unchanged. This is what I would call pumping: the rapid periodic rise
and fall of audio level caused by phase shifts, due to stations either
slightly off frequency or ionospheric Doppler shift.

These effects are common on MW, especially around sunrise and sunset.
I've also observed them on SW, when ionospheric effects cause a single
signal to flutter.

73,

Jim, KR1S
http://qrp.kearman.com/ <http://qrp.kearman.com/>


Re: ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

Joseph Miller <radiodxer2000@...>
 

Congratulations Rob, I knew you could do it!!!

73 de Joe, KJ8O, Troy, MI

--- On Tue, 2/2/10, Robert S.Ross VA3SW <va3sw@...> wrote:

From: Robert S.Ross VA3SW <va3sw@...>
Subject: [ultralightdx] ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!
To: "Ultralight List" <ultralightdx@...>
Date: Tuesday, February 2, 2010, 7:12 PM
Hi Guys:

  Well...since my last report yesterday, I have logged
3 NEW Stations
for the ULR Log which were # 799, # 800 and # 801 Heard on
ULTRALIGHT
RADIOS!! Number 799 was logged last night at Bedtime....and
the other 2
bringing me over the 800 mark were logged tonight at
SUNSET. Number 799
was a CALL CHANGE for the OVERALL LOG...and 800 and
801  are NEW to the
OVERALL LOG as well.

The trek to 800 ULR Stations heard began on
JAN/01/2008.....making the
total time elapsed to hit 800 Stations on ULR ......2 Years
and 33 Days.

Nice that # 800 was a LOW POWERED 500/57 Watts Station!!

I Logged # 700 on Oct/04/2009...so it took 2 days shy of 4
Months to get
the next 100 Stations.

It has been a lot of Fun and a lot of Work to get these
last 100
Stations......but now it's done and I can move on to the
next 100 New
Ones and # 900 somewhere down the road.

Radio Used for these Loggings is......SONY SRF-T615 ULR
BAREFOOT
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

ULR LOG TOTALS are now......801 Stations heard
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

73.......ROB VA3SW

Robert S. Ross
London, Ontario CANADA

*****************************************************************
690 WIST New Orleans, LA. Feb/01/2010 2255 EST 
EE   FAIR
Sports talk @ 2255-2300 EST. ID as "The Mighty 690 Your
Home for
Sports Radio". Talk by Male DJ then another ID as "You're
Tuned to
WIST New Orleans". Into more Sports Talk.

RELOG (NEW CALLS)....But NEW ULR #
799   10/5 KW
ROSS, ONT.
******************************************************************
950 WHVW Hyde Park, NY Feb/02/2010 1743 EST  EE 
  FAIR
Old 1920's Blues Song....Billie Holiday...Ma Rainey??? @
1743-46 EST.
ID Sung Out by Females as "WHVW". Into Oldies Song "Honey
Love @ 1746-
1749 EST. Then into the mix with WWJ on top.

NEW STN.       ULR # 800 
  500 Watts/57 Watts Nights
ROSS, ONT.
*******************************************************************
960 WEAV Plattsburgh, NY Feb/02/2010 1752 EST 
EE   FAIR
ID as "THE ZONE" @ 1752. Local Ad for "South Burlington,
VERMONT".
Another Local Ad. Public Service Announcement for the
"Asian
Longhorn Beetle" @ 1754...then into the Mix.

NEW STN.     ULR #
801   5 KW
ROSS, ONT.
********************************************************************




------------------------------------

Yahoo! Groups Links


    ultralightdx-fullfeatured@...



Re: ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

robert ross
 

carl_elissa wrote:
 

Thanks on the tip on the article about barefoot ulr dxing.Since my last post ,i did a search on the SRF-T615.I found 2 apparent sources.
http://www.sony.jp/overseas/products/SRF-T615JE/index_en.html

http://www.audiocubes2.com/brand/Sony/product/Sony_SRF-T615_Pocket_Radio.html?osCsid=45f414f99ce9e9e200f1708d18bde270

Carl DeWhitt
Maryville,Tn.

Carl.......The 2nd Link above for Audio Cubes II is where I purchased mine....and I think that's where most of the North American T615 Users got theirs too!! They have Good Service and it took about 2 weeks to receive the Radio.....

73...ROB VA3SW


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

Roy <roy.dyball@...>
 

Guy

When I ordered My Amidon rods 4,6,7.5" rods I also ordered 40/46, 165/46 and 630/46 (my mistake it is not 660) wire. I set about winding coils on all of the rods with different wire. After reading Ben Tongue article I was connived that the centre of the rod was the best part to wind the coil. Also knowing the Si4734 just adapted to the coil as long as it was in the inductance range specified in the chips notes this reinforced my belief to wind my coils in the centre to have the best Q.

Every time I moved up a rod or a wire size the results got better. I did not use the 630 strand Litz on the 4 or 6" rod as there is not enough room. Just like if you built a bigger aeroplane with a longer fuselage you would not use the wings from a smaller aeroplane to lift it, so it seemed to me to be the same that the wire size should be increased with rod size.

The DC resistance of the 630 Litz coil is so low that I can't read it. The same resistance associated with the same inductance of a 40/46 coil is a few ohms. So this must improve the Q for a start. My theory is that the larger wire size enables more of the rod to be covered by the coil thus enhancing the magnetic couple I don't know if it is specifically the Litz but maybe it is just the wire size, but I really would not consider using any other wire than Litz at that diameter.

I have been using the 630 Litz coil now for many days listening to distant overland stations as the sun comes up. I just rewound the 81 turn 40/46 coil slider coil to test it again. The 630 Litz coil when judged from a listening point of view reminds me of my Sony 7600GR with a good low noise floor with the signal coming out of and returning to the noise floor gently, plus the soft mute did not seem to bug me as much. On the other hand the 40/46 coil seemed to pick up more hash from the radios display creating a buzz noticeable at some frequencies along with the polling request for the RSSI and S/N indicators. I advise all members to experiment for themselves with a bit of wire and some rods. That's what the fun of ULDXing is and I hope we can all calmly disuses our results.

This points out that for the purest; at least two separate loopstick coils should be at hand. One for the top of the band and one for the bottom of the band.

Cheers Roy.

 

--- In ultralightdx@..., "thinkdx" wrote:
>
> Hi Roy, Yes, I checked mid and high band signals too, and observed the
> average reading over one minute. Any frequency I tried showed
> improvement with the coil at the same approx. position from the end of
> the rod (about 1-5/8", where inductance was 532 or so). As you
> mentioned, the improvement is not as great when you tune up in
> frequency. I made the video with 530 kHz, because there are steady,
> weak TIS stations audible on 530 from my location. I suppose I could
> have shown the effect in the video with other frequencies besides low
> band. Thanks for the tip on the high strand count 660 Litz. When I made
> an E100 slider a couple summers ago, I used 172/44 Litz, but have never
> tried any variety approaching 660 strands. Do you feel that the number
> of strands affects the noise level, or does it have to do with the coil
> wound in the middle? 73, Guy Atkins Puyallup, WA USA
> http://fivebelow.squarespace.com
>
> --- In ultralightdx@..., "Roy" roy.dyball@ wrote:
> >
> >
> > 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.
>


Re: ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

Carl DeWhitt
 

Thanks on the tip on the article about barefoot ulr dxing.Since my last post ,i did a search on the SRF-T615.I found 2 apparent sources.
http://www.sony.jp/overseas/products/SRF-T615JE/index_en.html

http://www.audiocubes2.com/brand/Sony/product/Sony_SRF-T615_Pocket_Radio.html?osCsid=45f414f99ce9e9e200f1708d18bde270

Carl DeWhitt
Maryville,Tn.

--- In ultralightdx@..., "Robert S.Ross VA3SW" <va3sw@...> wrote:

carl_elissa wrote:


Wow ! Congratulations ,Rob, on hitting the 800 mark !
Thanks!!! It was a FUN Ride!!



Is the Sony SRF-T615 still available for purchase ?
Yes.....but ONLY from JAPAN.....and it is NOT CHEAP! Close to $200 to
bring them to CANADA Delivered. I like it sooooo much I bought a Second
One so I can have one on each floor of the House! I have about 24 ULR
Radios...pretty much everything that has come along....and the T615 is
the KING as far as I'm concerned...but what do I know eh????



How about an article on how you log all those stations barefoot ?
Again,congratulations and on to 900 !
Carl DeWhitt
Maryville,Tn.
Well Carl.....that Article has ALREADY been done. A few weeks ago John
Bryant announced an Article on Barefoot DXing Techniques which was
written by 5 of us ULR DXers. The article is in the ULR FILES SECTION
and also on the DXer.ca Webpage under the ULR Files.

Check it out and see what some of the Top Barefoot Dxers do...and how we
do it!

73.....ROB

Robert S. Ross
London, Ontario CANADA


Re: ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

robert ross
 

carl_elissa wrote:
 

Wow ! Congratulations ,Rob, on hitting the 800 mark !

Thanks!!! It was a FUN Ride!!



Is the Sony SRF-T615 still available for purchase ?

Yes.....but ONLY from JAPAN.....and it is NOT CHEAP! Close to $200 to bring them to CANADA Delivered. I like it sooooo much I bought a Second One so I can have one on each floor of the House! I have about 24 ULR Radios...pretty much everything that has come along....and the T615 is the KING as far as I'm concerned...but what do I know eh????



How about an article on how you log all those stations barefoot ? Again,congratulations and on to 900 !
Carl DeWhitt
Maryville,Tn.

Well Carl.....that Article has ALREADY been done. A few weeks ago John Bryant announced an Article on Barefoot DXing Techniques which was written by 5 of us ULR DXers. The article is in the ULR FILES SECTION and also on the DXer.ca Webpage under the ULR Files.

Check it out and see what some of the Top Barefoot Dxers do...and how we do it!

73.....ROB

Robert S. Ross
London, Ontario CANADA


Re: ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

Carl DeWhitt
 

Wow ! Congratulations ,Rob, on hitting the 800 mark ! Is the Sony SRF-T615 still available for purchase ? How about an article on how you log all those stations barefoot ? Again,congratulations and on to 900 !
Carl DeWhitt
Maryville,Tn.

--- In ultralightdx@..., "Robert S.Ross VA3SW" <va3sw@...> wrote:

Hi Guys:

Well...since my last report yesterday, I have logged 3 NEW Stations
for the ULR Log which were # 799, # 800 and # 801 Heard on ULTRALIGHT
RADIOS!! Number 799 was logged last night at Bedtime....and the other 2
bringing me over the 800 mark were logged tonight at SUNSET. Number 799
was a CALL CHANGE for the OVERALL LOG...and 800 and 801 are NEW to the
OVERALL LOG as well.

The trek to 800 ULR Stations heard began on JAN/01/2008.....making the
total time elapsed to hit 800 Stations on ULR ......2 Years and 33 Days.

Nice that # 800 was a LOW POWERED 500/57 Watts Station!!

I Logged # 700 on Oct/04/2009...so it took 2 days shy of 4 Months to get
the next 100 Stations.

It has been a lot of Fun and a lot of Work to get these last 100
Stations......but now it's done and I can move on to the next 100 New
Ones and # 900 somewhere down the road.

Radio Used for these Loggings is......SONY SRF-T615 ULR BAREFOOT
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

ULR LOG TOTALS are now......801 Stations heard
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

73.......ROB VA3SW

Robert S. Ross
London, Ontario CANADA

*****************************************************************
690 WIST New Orleans, LA. Feb/01/2010 2255 EST EE FAIR
Sports talk @ 2255-2300 EST. ID as "The Mighty 690 Your Home for
Sports Radio". Talk by Male DJ then another ID as "You're Tuned to
WIST New Orleans". Into more Sports Talk.

RELOG (NEW CALLS)....But NEW ULR # 799 10/5 KW
ROSS, ONT.
******************************************************************
950 WHVW Hyde Park, NY Feb/02/2010 1743 EST EE FAIR
Old 1920's Blues Song....Billie Holiday...Ma Rainey??? @ 1743-46 EST.
ID Sung Out by Females as "WHVW". Into Oldies Song "Honey Love @ 1746-
1749 EST. Then into the mix with WWJ on top.

NEW STN. ULR # 800 500 Watts/57 Watts Nights
ROSS, ONT.
*******************************************************************
960 WEAV Plattsburgh, NY Feb/02/2010 1752 EST EE FAIR
ID as "THE ZONE" @ 1752. Local Ad for "South Burlington, VERMONT".
Another Local Ad. Public Service Announcement for the "Asian
Longhorn Beetle" @ 1754...then into the Mix.

NEW STN. ULR # 801 5 KW
ROSS, ONT.
********************************************************************


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

Gary DeBock
 

Hi Scott and Roy,
 
Thanks for your comments, especially those concerning our ULR group tradition of courtesy, and mutual respect.
 
Although our group has grown rapidly to over 500 members (with somewhat divergent interests), it has been one tradition that we have tried to maintain at all costs. It's always much more pleasant to work toward a common goal, rather than a common row :-) 
 
I'm sure that Guy and I will enjoy working together with you in trying different combinations of coils and Litz wire, to see if we can squeeze any more AM sensitivity out of the 7.5" PL-380 loopstick design. It appears that 7.5" PL-380 loopsticks could be designed to favor either the low band, high band, or even the LW band. Ironically, this was the same situation that led John, Guy and I to develop the E100 Slider models two years ago. Rather than kick off another controversy, I'll keep quiet about weird plans to test out a PL-380 7.5" Slider model to allow the optimization of all three band segments in one PL-380 hotrod model :-)    
 
73, Gary    
 
  
 
 
 
In a message dated 2/2/2010 6:49:15 P.M. Pacific Standard Time, sdwillingham@... writes:

 



To All,

I'd like to reinforce Gary's sentiment here. Since joining this
group, I've found everyone to be helpful in pursuing common
goals. And mutual respect can keep the group on-track and
useful.

I'll make a little confession. When I first watched Guy's
video, I started to type up an impatient response about how it
was done all wrong, etc. Then I thought better of it. The
Si4734 does many things entirely different from past designs,
and it's foolish to expect that one or two explanations will
reach everyone (or even be clear for that matter). So I wrote a
new post, concentrating on just one misunderstanding that I felt
I could clarify. Roy later responded with his thorough and
patient post. The resulting thread is far better than it might
have been.

Cheers and Respect,
Scott

--- In ultralightdx@yahoogroups.com, D1028Gary@... wrote:
> 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)


ULR DX.......# 800 Logged....and # 801 Too!!! FINALLY!!

robert ross
 

Hi Guys:

Well...since my last report yesterday, I have logged 3 NEW Stations for the ULR Log which were # 799, # 800 and # 801 Heard on ULTRALIGHT RADIOS!! Number 799 was logged last night at Bedtime....and the other 2 bringing me over the 800 mark were logged tonight at SUNSET. Number 799 was a CALL CHANGE for the OVERALL LOG...and 800 and 801 are NEW to the OVERALL LOG as well.

The trek to 800 ULR Stations heard began on JAN/01/2008.....making the total time elapsed to hit 800 Stations on ULR ......2 Years and 33 Days.

Nice that # 800 was a LOW POWERED 500/57 Watts Station!!

I Logged # 700 on Oct/04/2009...so it took 2 days shy of 4 Months to get the next 100 Stations.

It has been a lot of Fun and a lot of Work to get these last 100 Stations......but now it's done and I can move on to the next 100 New Ones and # 900 somewhere down the road.

Radio Used for these Loggings is......SONY SRF-T615 ULR BAREFOOT
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

ULR LOG TOTALS are now......801 Stations heard
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

73.......ROB VA3SW

Robert S. Ross
London, Ontario CANADA

*****************************************************************
690 WIST New Orleans, LA. Feb/01/2010 2255 EST EE FAIR
Sports talk @ 2255-2300 EST. ID as "The Mighty 690 Your Home for
Sports Radio". Talk by Male DJ then another ID as "You're Tuned to
WIST New Orleans". Into more Sports Talk.

RELOG (NEW CALLS)....But NEW ULR # 799 10/5 KW
ROSS, ONT.
******************************************************************
950 WHVW Hyde Park, NY Feb/02/2010 1743 EST EE FAIR
Old 1920's Blues Song....Billie Holiday...Ma Rainey??? @ 1743-46 EST.
ID Sung Out by Females as "WHVW". Into Oldies Song "Honey Love @ 1746-
1749 EST. Then into the mix with WWJ on top.

NEW STN. ULR # 800 500 Watts/57 Watts Nights
ROSS, ONT.
*******************************************************************
960 WEAV Plattsburgh, NY Feb/02/2010 1752 EST EE FAIR
ID as "THE ZONE" @ 1752. Local Ad for "South Burlington, VERMONT".
Another Local Ad. Public Service Announcement for the "Asian
Longhorn Beetle" @ 1754...then into the Mix.

NEW STN. ULR # 801 5 KW
ROSS, ONT.
********************************************************************


Re: Measuring PL-380 Soft-Mute

jim_kr1s <jkearman@...>
 


--- In ultralightdx@..., "sdwillingham" wrote:

>
> This suggests one way to defeat the effect: just off-tune
> from the carrier by 1 kHz, which engages the soft-mute.
> Then turn your volume knob up by 2-clicks (PL-380) or
> 4-clicks (PL-300). As long as you can live with the offset
> filtering, this should get rid of the pumping effect. Since
> you are already dealing with low-SNR signals, this technique
> should not further degrade reception.

Scott,

This is true if there is only one steady signal, or at least no phase difference between multiple signals. When two signals on the same frequency are out of phase, when they cancel each other, the drop in volume is quite a bit more noticeable on the G8/PL-300wt than on the PL-380, even when tuned to the carrier frequency.

You can raise the audio floor by turning up the volume, but then the audio ceiling is increased by the same amount, so the effect is unchanged. This is what I would call pumping: the rapid periodic rise and fall of audio level caused by phase shifts, due to stations either slightly off frequency or ionospheric Doppler shift.

These effects are common on MW, especially around sunrise and sunset.  I've also observed them on SW, when ionospheric effects cause a single signal to flutter.

73,

Jim, KR1S
http://qrp.kearman.com/ 


Re: Measuring PL-380 Soft-Mute

Tony Germanotta
 

Thanks Scott. That had been my experience with the PL-310, that the "mute" is just an drop in audio not signal, despite the SN dropping to 0 on the meter. I guess you could find a signal so weak that you run out of clicks on the volume knob, but I generally use very efficient headphones and have never had that happen. (It looks like the 310 is also a 4 clicker.) Now I won't worry when I offtune that I am somehow losing signal intelligence along with my drop in volume.  This is an amazing chip you designed, and they did an amazing job on these radios. I think I will live with the need to work my volume control rather than move to the PL-380 with its smaller, less efficient loopstick.


On Feb 2, 2010, at 6:12 PM, sdwillingham wrote:

 


Good question. It is just a volume change in the audio
processing. In the audio world, this would be called
'downward expansion'. (Well, not quite. Expansion would
just be based on the signal volume, whereas the soft-mute
is based on calculated SNR.)

This suggests one way to defeat the effect: just off-tune
from the carrier by 1 kHz, which engages the soft-mute.
Then turn your volume knob up by 2-clicks (PL-380) or
4-clicks (PL-300). As long as you can live with the offset
filtering, this should get rid of the pumping effect. Since
you are already dealing with low-SNR signals, this technique
should not further degrade reception.

-Scott-

--- In ultralightdx@yahoogroups.com, Richard Berler > wrote:
>
> Hi Scott
>  
> When you say that the volume is lowered by 6dB (or 12 dB on the 310), does that mean that the signal has been attenuated or that the volume alone is impacted? If volume only, would one recover the equivalent audio by adjusting the volume?
>  
> Heatwave
>
> --- On Sun, 1/31/10, sdwillingham ...> wrote:
>
>
> From: sdwillingham ...>
> Subject: [ultralightdx] Re: Measuring PL-380 Soft-Mute
> To: ultralightdx@yahoogroups.com
> Date: Sunday, January 31, 2010, 1:00 AM
>
>
>  
>
>
>
> Further info: Via my USB-equipped PL-300wt, I can read out that
> its soft-mute is configured with a threshold at SNR = 6 dB and
> the soft-mute slope is 2 dB/dB. This means that for each dB
> that the SNR reads below 6, the volume is reduced by 2 dB. At
> SNR = 0 dB, the maximum volume reduction is 12 dB.
>
> I suspect that the PL-380 simply changes the soft-mute slope
> parameter to 1 dB/dB, so it reduces the gain more gently and to
> a maximum of 6 dB. I'll have to confirm that when I get around
> to modifying my PL-380 with a USB interface.
>
> -Scott-
>
> --- In ultralightdx@ yahoogroups. com, "sdwillingham" wrote:
> >
> >
> > For comparison, my stock PL-300wt measures about 12 dB soft-mute.
> >
> > -Scott-
> >
> > --- In ultralightdx@ yahoogroups. com, "sdwillingham" wrote:
> > >
> > >
> > > Hi All,
> > >
> > > It has been debated occasionally whether the PL-380 has
> > > soft-mute. The short answer is: mine does (PL-380 2009.9 ver 1)
> > > and it's fairly easy to measure. The procedure is to tune a
> > > strong, steady station, measure its average audio level, then
> > > off-tune by 1kHz, and finally remeasure its level.
> > >
> > > To measure the average level, use a free computer recording
> > > program. I think many of you have Audacity and, while it's not
> > > my favorite, it works fine for this purpose. Here's what I did:
> > >
> > > 1) Install Audacity and launch the program.
> > > 2) Attach an audio cable from your PL-380 to the computer's
> > > mic or line input.
> > > 3) Turn the radio on, tune in a strong station with good
> > > SNR, and set the radio's volume control to 7 or 8. Also,
> > > set the IF filter to 6 kHz.
> > > 4) Back in Audacity, locate the input meter (rightmost), and
> > > click on meter to start monitoring the input. (Stretch the
> > > meter toolbar out to see the levels better.)
> > > 5) Next, you'll have to locate your system's recording mixer
> > > and adjust the recording level. I can't tell you the
> > > specifics, since this depends on your sound card. If you
> > > are using a 'mic' input, try to turn off its 'boost'
> > > setting. Adjust the mixer level until the average signal
> > > shows about -15 dB or so on the Audacity meter.
> > > 6) Now monitor the signal's running peak (a dark-red
> > > vertical line on the meter). Determine a where this peak
> > > sits for a particular talker's voice or song. For
> > > example, I'm seeing about -12 dB on my meter now.
> > > 7) Tune the radio off-carrier by 1kHz. Even for strong
> > > signals, this causes the radio to indicate and SNR of 0 dB
> > > which kicks-in the soft-mute function. Measure the peak
> > > level again. I see about -18 dB now. So my conclusion
> > > is that my radio has about 6 dB maximum soft-mute.
> > >
> > > The conclusion is, PL-380 2009.9 ver 1 radios have about 6 dB
> > > soft-mute. This probably also means that the soft-mute
> > > threshold is 6 dB, but that is not certain. We can also
> > > conclude that Tecsun is setting this deliberately, since it does
> > > not match with the Si4734 defaults (neither firmware 2.0 or
> > > 4.0). Perhaps one of you with a 'new' model can test if the
> > > settings have been changed.
> > >
> > > -Scott-
> > >
> >
>



Re: Measuring PL-380 Soft-Mute

sdwillingham
 

Good question. It is just a volume change in the audio
processing. In the audio world, this would be called
'downward expansion'. (Well, not quite. Expansion would
just be based on the signal volume, whereas the soft-mute
is based on calculated SNR.)

This suggests one way to defeat the effect: just off-tune
from the carrier by 1 kHz, which engages the soft-mute.
Then turn your volume knob up by 2-clicks (PL-380) or
4-clicks (PL-300). As long as you can live with the offset
filtering, this should get rid of the pumping effect. Since
you are already dealing with low-SNR signals, this technique
should not further degrade reception.

-Scott-

--- In ultralightdx@..., Richard Berler <lrdheat@...> wrote:

Hi Scott
 
When you say that the volume is lowered by 6dB (or 12 dB on the 310), does that mean that the signal has been attenuated or that the volume alone is impacted? If volume only, would one recover the equivalent audio by adjusting the volume?
 
Heatwave

--- On Sun, 1/31/10, sdwillingham <sdwillingham@...> wrote:


From: sdwillingham <sdwillingham@...>
Subject: [ultralightdx] Re: Measuring PL-380 Soft-Mute
To: ultralightdx@...
Date: Sunday, January 31, 2010, 1:00 AM


 



Further info: Via my USB-equipped PL-300wt, I can read out that
its soft-mute is configured with a threshold at SNR = 6 dB and
the soft-mute slope is 2 dB/dB. This means that for each dB
that the SNR reads below 6, the volume is reduced by 2 dB. At
SNR = 0 dB, the maximum volume reduction is 12 dB.

I suspect that the PL-380 simply changes the soft-mute slope
parameter to 1 dB/dB, so it reduces the gain more gently and to
a maximum of 6 dB. I'll have to confirm that when I get around
to modifying my PL-380 with a USB interface.

-Scott-

--- In ultralightdx@ yahoogroups. com, "sdwillingham" <sdwillingham@ ...> wrote:


For comparison, my stock PL-300wt measures about 12 dB soft-mute.

-Scott-

--- In ultralightdx@ yahoogroups. com, "sdwillingham" <sdwillingham@ > wrote:


Hi All,

It has been debated occasionally whether the PL-380 has
soft-mute. The short answer is: mine does (PL-380 2009.9 ver 1)
and it's fairly easy to measure. The procedure is to tune a
strong, steady station, measure its average audio level, then
off-tune by 1kHz, and finally remeasure its level.

To measure the average level, use a free computer recording
program. I think many of you have Audacity and, while it's not
my favorite, it works fine for this purpose. Here's what I did:

1) Install Audacity and launch the program.
2) Attach an audio cable from your PL-380 to the computer's
mic or line input.
3) Turn the radio on, tune in a strong station with good
SNR, and set the radio's volume control to 7 or 8. Also,
set the IF filter to 6 kHz.
4) Back in Audacity, locate the input meter (rightmost), and
click on meter to start monitoring the input. (Stretch the
meter toolbar out to see the levels better.)
5) Next, you'll have to locate your system's recording mixer
and adjust the recording level. I can't tell you the
specifics, since this depends on your sound card. If you
are using a 'mic' input, try to turn off its 'boost'
setting. Adjust the mixer level until the average signal
shows about -15 dB or so on the Audacity meter.
6) Now monitor the signal's running peak (a dark-red
vertical line on the meter). Determine a where this peak
sits for a particular talker's voice or song. For
example, I'm seeing about -12 dB on my meter now.
7) Tune the radio off-carrier by 1kHz. Even for strong
signals, this causes the radio to indicate and SNR of 0 dB
which kicks-in the soft-mute function. Measure the peak
level again. I see about -18 dB now. So my conclusion
is that my radio has about 6 dB maximum soft-mute.

The conclusion is, PL-380 2009.9 ver 1 radios have about 6 dB
soft-mute. This probably also means that the soft-mute
threshold is 6 dB, but that is not certain. We can also
conclude that Tecsun is setting this deliberately, since it does
not match with the Si4734 defaults (neither firmware 2.0 or
4.0). Perhaps one of you with a 'new' model can test if the
settings have been changed.

-Scott-


Re: Si4734 Hardware and Software Guides

sdwillingham
 

Roy,

I am using the daughterboard-only for my interface within the
radio. The base adapter, however, provides an interface for two
things: 1) Downloading programs to flash memory. 2) It has
a very slick 2-wire interface to the MCU which is used for
in-circuit debugging. With the development tools, you can
run/stop/trace your code graphically.

The daughtercards are available separately for about $10 each.
I think the base adapter is $15-20. I bought one of each.
You probably want to buy the "getting-started" kit first,
however, to get all the software tools. Just add the -F321
daughtercard separately.

I use a full version of the Keil compiler. The same compiler
is used in the Silabs kits, but is a restricted version (I think
it mainly restricts program size to 2kB). Right now, I am not
using the development-kit IDE. Instead, I use the compiler with
Gnu-make and some complex Makefiles developed by our firmware
group. (The same compiler is used for the Si47XX internal MCU
firmware.)

Regarding USB code, my interface uses the code from the
reference design Zip that I linked to earlier in this thread.
This code uses a standard HID interface to the PC, so there are
no drivers needed. Some PC-side C-code examples can be found
in that zip file too. (Just disregard the complicated
audio-streaming code and refer to the control/command code.)
I have not done any programming on the PC side, however,
because I'm able to use the Silabs standard Si47xx evaluation
GUI on that side.

On the daughtercard side, I'm sure I can help you get the basic
USB communication going, which is 90% of the code. (And the
code I'm using is barely modified from the code that's already
publically available.) Only about 10% of my code deals with
the EVB/GUI command set and communication with the radio chip.

-Scott-

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


Scott

Thank you for putting me straight about the SPI connection to the MCU.

Am I correct in assuming that you are only using the daughter board
alone and not the base board connected to the daughter board? Is the
daughter board available on its own from Mouser?

Scott what version of C are you using. Is the Si labs development
environment and tools all one would need to get an interface working
with the ability to slot in my own code? Are the PC-USB libraries
included in the development environment?

I will probably order one of these MCU boards and have a go. There goes
another life time LOL. I will look forward to your results with the new
board. I also thought it made good sense to utilise the existing USB
connector on the 380 or the 310.

Cheers Roy.--- In ultralightdx@..., "sdwillingham"
<sdwillingham@> wrote:




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_D\;
C_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: Guy Atkin's Independent Testing of PL-380 7.5" Loopstick

Guy Atkins
 

Hi Roy, Yes, I checked mid and high band signals too, and observed the average reading over one minute. Any frequency I tried showed improvement with the coil at the same approx. position from the end of the rod (about 1-5/8", where inductance was 532 or so). As you mentioned, the improvement is not as great when you tune up in frequency. I made the video with 530 kHz, because there are steady, weak TIS stations audible on 530 from my location. I suppose I could have shown the effect in the video with other frequencies besides low band. Thanks for the tip on the high strand count 660 Litz. When I made an E100 slider a couple summers ago, I used 172/44 Litz, but have never tried any variety approaching 660 strands. Do you feel that the number of strands affects the noise level, or does it have to do with the coil wound in the middle? 73, Guy Atkins Puyallup, WA USA http://fivebelow.squarespace.com 


--- In ultralightdx@..., "Roy" wrote:
>
>
> 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.


Re: Measuring PL-380 Soft-Mute

lrdheat
 

Hi Scott
 
When you say that the volume is lowered by 6dB (or 12 dB on the 310), does that mean that the signal has been attenuated or that the volume alone is impacted? If volume only, would one recover the equivalent audio by adjusting the volume?
 
Heatwave


--- On Sun, 1/31/10, sdwillingham wrote:

From: sdwillingham Subject: [ultralightdx] Re: Measuring PL-380 Soft-Mute
To: ultralightdx@...
Date: Sunday, January 31, 2010, 1:00 AM

 
Further info: Via my USB-equipped PL-300wt, I can read out that
its soft-mute is configured with a threshold at SNR = 6 dB and
the soft-mute slope is 2 dB/dB. This means that for each dB
that the SNR reads below 6, the volume is reduced by 2 dB. At
SNR = 0 dB, the maximum volume reduction is 12 dB.

I suspect that the PL-380 simply changes the soft-mute slope
parameter to 1 dB/dB, so it reduces the gain more gently and to
a maximum of 6 dB. I'll have to confirm that when I get around
to modifying my PL-380 with a USB interface.

-Scott-

--- In ultralightdx@ yahoogroups. com, "sdwillingham" wrote:
>
>
> For comparison, my stock PL-300wt measures about 12 dB soft-mute.
>
> -Scott-
>
> --- In ultralightdx@ yahoogroups. com, "sdwillingham" wrote:
> >
> >
> > Hi All,
> >
> > It has been debated occasionally whether the PL-380 has
> > soft-mute. The short answer is: mine does (PL-380 2009.9 ver 1)
> > and it's fairly easy to measure. The procedure is to tune a
> > strong, steady station, measure its average audio level, then
> > off-tune by 1kHz, and finally remeasure its level.
> >
> > To measure the average level, use a free computer recording
> > program. I think many of you have Audacity and, while it's not
> > my favorite, it works fine for this purpose. Here's what I did:
> >
> > 1) Install Audacity and launch the program.
> > 2) Attach an audio cable from your PL-380 to the computer's
> > mic or line input.
> > 3) Turn the radio on, tune in a strong station with good
> > SNR, and set the radio's volume control to 7 or 8. Also,
> > set the IF filter to 6 kHz.
> > 4) Back in Audacity, locate the input meter (rightmost), and
> > click on meter to start monitoring the input. (Stretch the
> > meter toolbar out to see the levels better.)
> > 5) Next, you'll have to locate your system's recording mixer
> > and adjust the recording level. I can't tell you the
> > specifics, since this depends on your sound card. If you
> > are using a 'mic' input, try to turn off its 'boost'
> > setting. Adjust the mixer level until the average signal
> > shows about -15 dB or so on the Audacity meter.
> > 6) Now monitor the signal's running peak (a dark-red
> > vertical line on the meter). Determine a where this peak
> > sits for a particular talker's voice or song. For
> > example, I'm seeing about -12 dB on my meter now.
> > 7) Tune the radio off-carrier by 1kHz. Even for strong
> > signals, this causes the radio to indicate and SNR of 0 dB
> > which kicks-in the soft-mute function. Measure the peak
> > level again. I see about -18 dB now. So my conclusion
> > is that my radio has about 6 dB maximum soft-mute.
> >
> > The conclusion is, PL-380 2009.9 ver 1 radios have about 6 dB
> > soft-mute. This probably also means that the soft-mute
> > threshold is 6 dB, but that is not certain. We can also
> > conclude that Tecsun is setting this deliberately, since it does
> > not match with the Si4734 defaults (neither firmware 2.0 or
> > 4.0). Perhaps one of you with a 'new' model can test if the
> > settings have been changed.
> >
> > -Scott-
> >
>



Re: Si4734 Hardware and Software Guides

Roy <roy.dyball@...>
 

Scott

Thank you for putting me straight about the SPI connection to the MCU.

Am I correct in assuming that you are only using the daughter board alone and not the base board connected to the daughter board? Is the daughter board available on its own from Mouser?

Scott what version of C are you using. Is the Si labs development environment and tools all one would need to get an interface working with the ability to slot in my own code? Are the PC-USB libraries included in the development environment?

I will probably order one of these MCU boards and have a go. There goes another life time LOL. I will look forward to your results with the new board. I also thought it made good sense to utilise the existing USB connector on the 380 or the 310.

Cheers Roy.--- In ultralightdx@..., "sdwillingham" wrote:
>
>
>
>
> 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.
> >
>


MI LOG

wa8lcz
 

Jan 26
1260 WWMK Cleveland OH 1405 EST 10k 5k disney
1250 WLEM Emporium PA 1906 EST 2.5k 30w country
1230 WTKG Grand Rapids MI 1934 EST 1k 1k

Jan 28
1390 WMPO Middleport OH 0801 EST 5k day espn sports

Jan 29
1490 WMPX Midland MI 0830 EST 1k 1k oldies patsy cline crazy
1490 WABJ Adrian MI 0836 EST 1k 1k newstalk

Jan 31
680 WPTF Raleigh NC 0815 EST 50k 50k newstalk ant pattern SE
620 WKHB Irwin PA 0829 EST 5.5k 50w oldies ant pat NW
690 WELD Fisher WV 1835 EST 3k 14w oldies ant pat NW


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
> > |
> > Visit Your Group on the Web
> > Messages<http://groups.yahoo.com/group/ultralightdx/messages;_ylc=X3oDMTJmN24zcDRyBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNtc2dzBHN0aW1lAzEyNjUxMDU2MTA->|
> > Files|
> > Photos|
> > Links|
> > Database|
> > Polls<http://groups.yahoo.com/group/ultralightdx/polls;_ylc=X3oDMTJnajk3b21oBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNwb2xscwRzdGltZQMxMjY1MTA1NjEw>|
> > Members|
> > Calendar
> > MARKETPLACE
> >
> > Going Green: Your Yahoo! Groups resource for green living
> > [image: Yahoo! Groups]<http://groups.yahoo.com/;_ylc=X3oDMTJlMzF0MDgzBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNnZnAEc3RpbWUDMTI2NTEwNTYxMA-->
> > Change settings via the Web(Yahoo! ID required)
> > Change settings via email: Switch delivery to Individualultralightdx-normal@...?subject=Email+Delivery:+Indiviual+Email>| Switch
> > format to Traditionalultralightdx-traditional@...?subject=Change+Delivery+Format:+Traditional>
> > Visit Your Group
> > |
> > Yahoo! Groups Terms of Use | Unsubscribe
> > ultralightdx-unsubscribe@...?subject=Unsubscribe>
> >
>


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->|
> > Visit Your Group on the Webyahoo.com/group/ultralightdx;_ylc=X3oDMTJkZmlnOWJmBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNocARzdGltZQMxMjY1MTA1NjEw>
> > Messagesyahoo.com/group/ultralightdx/messages;_ylc=X3oDMTJmN24zcDRyBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNtc2dzBHN0aW1lAzEyNjUxMDU2MTA->|
> > Files<http://groups.yahoo.com/group/ultralightdx/files;_ylc=X3oDMTJnYjNxZW8yBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNmaWxlcwRzdGltZQMxMjY1MTA1NjEw>|
> > Photosyahoo.com/group/ultralightdx/photos;_ylc=X3oDMTJmbDRnN2Y5BF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNwaG90BHN0aW1lAzEyNjUxMDU2MTA->|
> > Linksyahoo.com/group/ultralightdx/links;_ylc=X3oDMTJncnZlaWc2BF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNsaW5rcwRzdGltZQMxMjY1MTA1NjEw>|
> > Databaseyahoo.com/group/ultralightdx/database;_ylc=X3oDMTJkaTRtdnVnBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNkYgRzdGltZQMxMjY1MTA1NjEw>|
> > Pollsyahoo.com/group/ultralightdx/polls;_ylc=X3oDMTJnajk3b21oBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNwb2xscwRzdGltZQMxMjY1MTA1NjEw>|
> > Membersyahoo.com/group/ultralightdx/members;_ylc=X3oDMTJmdWR2bnVwBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNtYnJzBHN0aW1lAzEyNjUxMDU2MTA->|
> > Calendar<http://groups.yahoo.com/group/ultralightdx/calendar;_ylc=X3oDMTJlaGpyZWJxBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNjYWwEc3RpbWUDMTI2NTEwNTYxMA-->
> > MARKETPLACE
> >
> > Going Green: Your Yahoo! Groups resource for green livingyahoo.com/SIG=14kb6ut8b/M=493064.13814333.13821539.13298430/D=groups/S=1706058037:MKP1/Y=YAHOO/EXP=1265112810/L=/B=zQkXCkPDhEo-/J=1265105610701560/K=cuHqeCxtv1ZQsjAX2sXl9w/A=5922843/R=0/SIG=11ckn2mo6/*http://advision.webevents.yahoo.com/green/>
> > [image: Yahoo! Groups]yahoo.com/;_ylc=X3oDMTJlMzF0MDgzBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNnZnAEc3RpbWUDMTI2NTEwNTYxMA-->
> > Change settings via the Webyahoo.com/group/ultralightdx/join;_ylc=X3oDMTJnY2Q0ZWs2BF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNzdG5ncwRzdGltZQMxMjY1MTA1NjEw>(Yahoo! ID required)
> > Change settings via email: Switch delivery to Individualultralightdx-normal@yahoogroups.com?subject=Email+Delivery:+Indiviual+Email>| Switch
> > format to Traditionalultralightdx-traditional@yahoogroups.com?subject=Change+Delivery+Format:+Traditional>
> > Visit Your Group
> > yahoo.com/group/ultralightdx;_ylc=X3oDMTJlMTZlcjZiBF9TAzk3MzU5NzE1BGdycElkAzIxNjE0MDc2BGdycHNwSWQDMTcwNjA1ODAzNwRzZWMDZnRyBHNsawNocGYEc3RpbWUDMTI2NTEwNTYxMA-->|
> > Yahoo! Groups Terms of Use yahoo.com/info/terms/>| Unsubscribe
> > ultralightdx-unsubscribe@yahoogroups.com?subject=Unsubscribe>
> >
>


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