Date   

Re: Calling John Bryant / Firsts and distance records

bjohnorcas@...
 

THANKS, PAUL....

I have no idea what happened to your first note. I'll be doinm a List
update when I get back to Stillwater in a few days.

John B.

Hi John,

I mailed you some time back regarding firsts and distance records, I guess
you didn't receive it so here goes again:

I have worked out that my first UL loggings from North America were as
follows.

WWZN Boston MA, USA, 1510, 2-10-08, Sony SRF-59, Barefoot
(50 kw night 2941 miles / 4732 km)
CKEC New Glasgow NS, Canada, 1320, 2-10-08, Sony SRF-59, Barefoot
(25 kw night 2468 miles / 3972 km)

As for Unlimited class first one was

WTNI Biloxi, MS, 1640, 2-10-08, Sony SRF-59, Unlimited class
(1kw night 4214 miles / 6782 km)

These will also be of interest - looks like a new record for 50 kw:
WWVA, Wheeling WV, 1170, 4-4-08, Sony SRF-59 Barefoot
3425 miles / 5512 km.

Same for 10kw:
CBI, Sydney NS, 1140, 3-24-08,Sony SRF-59 Barefoot, 2351 miles / 3783 km

Nice 5 kw catch:
WLAM, lewiston, ME, 1470, 4-3-08, SRF-59 Barefoot, 2831 miles / 4557 km

New 1 kw record? (this one does run 1kw nights - right?)
CKNB, Campbellton, NB, 950, 4-4-08, SRF-59 Barefoot, 2530 miles / 4072 km

I also have a slew of 1 kw x band loggings unlimited class mostly using a
4 foot loop with the SRF59.

1630 WRDW Augusta GA 1 05:35 30/03/2008 3788 miles 6096
km
1650 WHKT Portsmouth VA 1 05:32 30/03/2008 3399 5470
1670 WVVM Dry Branch, GA 1 05:37 30/03/2008 3887 6256
1680 WLAA Winter Garden, FL 1 05:40 30/03/2008 4019 6468
1620 WDHP Saint Croix USVI 1 06:10 02/04/2008 3931 6326
1700 WEUP Huntsville, AL 1 05:45 02/04/2008 3909 6292
1660 WFNA Charlotte NC 1 05:50 02/04/2008 3657 5885

I am fairly sure that I have had KVNS on 1700 Barefoot this would be 4794
miles but not willing to claim with no id - the station heard had oldies
and KVNS is usually dominant here on this freq - amazing when you think
they run 880 watts at night.

Hope these logs are of interest.

have you thought of a flea class for reception of 1 watters - I have one
at about 270 miles!.

regards for now

Paul Logan
Lisnaskea, N. Ireland.


bjohnorcas@rockisland.com wrote: Paul,

You might check the World Records at various transmitter powers. You
might
be setting records for 50 kW stations, for instance. In any case, a
great
set of loggings!

John Bryant








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My first image on the SRF-59

John Cereghin <jcereghin@...>
 


fanatical mega-loopstick question

sloshatron <wa1gwh@...>
 

Hi Gary;

When you measure the recycled coils on the LCR meter, are you
checking only the L or are you somehow taking into account any C
differences between the original and tranplant coils (either on or
off the ferrite bars)? This would be the distributed capacity of the
coils.

If this is working with just L measurements that would be great and
much easier for folks to duplicate.

Also, I'm still thinking about air core coils (small loop antenna
style) to replace the original ferrite loopstick. I realized that if
spider web construction was used it would be much easier to take off
turns and portions of turns and if necessary to add them back on if
the best spot was missed in the iterative alignment process. A
spider web coil form could be cut out of plastic with one spoke
extending way out to mount the form to the radio in the same way as
your ruler idea.

TNX,

Garry Nichols
near Syracuse, NY


Re: Calling John Bryant / Firsts and distance records

Dennis Gibson <wb6tnb@...>
 

Paul - is your SRF-59 stock (not tweaked for best performance)? Are
your non expanded band logs barefoot or with the loop?

73

--- In ultralightdx@yahoogroups.com, Paul Logan <paulloganradio@...>
wrote:

Hi John,

I mailed you some time back regarding firsts and distance records, I
guess you didn't receive it so here goes again:

I have worked out that my first UL loggings from North America were
as follows.

WWZN Boston MA, USA, 1510, 2-10-08, Sony SRF-59, Barefoot
(50 kw night 2941 miles / 4732 km)
CKEC New Glasgow NS, Canada, 1320, 2-10-08, Sony SRF-59, Barefoot
(25 kw night 2468 miles / 3972 km)

As for Unlimited class first one was

WTNI Biloxi, MS, 1640, 2-10-08, Sony SRF-59, Unlimited class
(1kw night 4214 miles / 6782 km)

These will also be of interest - looks like a new record for 50 kw:
WWVA, Wheeling WV, 1170, 4-4-08, Sony SRF-59 Barefoot
3425 miles / 5512 km.

Same for 10kw:
CBI, Sydney NS, 1140, 3-24-08,Sony SRF-59 Barefoot, 2351 miles / 3783 km

Nice 5 kw catch:
WLAM, lewiston, ME, 1470, 4-3-08, SRF-59 Barefoot, 2831 miles / 4557 km

New 1 kw record? (this one does run 1kw nights - right?)
CKNB, Campbellton, NB, 950, 4-4-08, SRF-59 Barefoot, 2530 miles /
4072 km

I also have a slew of 1 kw x band loggings unlimited class mostly
using a 4 foot loop with the SRF59.

1630 WRDW Augusta GA 1 05:35 30/03/2008 3788 miles
6096 km
1650 WHKT Portsmouth VA 1 05:32 30/03/2008 3399 5470
1670 WVVM Dry Branch, GA 1 05:37 30/03/2008 3887 6256
1680 WLAA Winter Garden, FL 1 05:40 30/03/2008 4019 6468
1620 WDHP Saint Croix USVI 1 06:10 02/04/2008 3931
6326
1700 WEUP Huntsville, AL 1 05:45 02/04/2008 3909 6292
1660 WFNA Charlotte NC 1 05:50 02/04/2008 3657 5885

I am fairly sure that I have had KVNS on 1700 Barefoot this would be
4794 miles but not willing to claim with no id - the station heard had
oldies and KVNS is usually dominant here on this freq - amazing when
you think they run 880 watts at night.

Hope these logs are of interest.

have you thought of a flea class for reception of 1 watters - I
have one at about 270 miles!.

regards for now

Paul Logan
Lisnaskea, N. Ireland.


Calling John Bryant / Firsts and distance records

Paul Logan
 

Hi John,

I mailed you some time back regarding firsts and distance records, I guess you didn't receive it so here goes again:

I have worked out that my first UL loggings from North America were as follows.

WWZN Boston MA, USA, 1510, 2-10-08, Sony SRF-59, Barefoot
(50 kw night 2941 miles / 4732 km)
CKEC New Glasgow NS, Canada, 1320, 2-10-08, Sony SRF-59, Barefoot
(25 kw night 2468 miles / 3972 km)

As for Unlimited class first one was

WTNI Biloxi, MS, 1640, 2-10-08, Sony SRF-59, Unlimited class
(1kw night 4214 miles / 6782 km)

These will also be of interest - looks like a new record for 50 kw:
WWVA, Wheeling WV, 1170, 4-4-08, Sony SRF-59 Barefoot
3425 miles / 5512 km.

Same for 10kw:
CBI, Sydney NS, 1140, 3-24-08,Sony SRF-59 Barefoot, 2351 miles / 3783 km

Nice 5 kw catch:
WLAM, lewiston, ME, 1470, 4-3-08, SRF-59 Barefoot, 2831 miles / 4557 km

New 1 kw record? (this one does run 1kw nights - right?)
CKNB, Campbellton, NB, 950, 4-4-08, SRF-59 Barefoot, 2530 miles / 4072 km

 I also have a slew of 1 kw x band loggings unlimited class mostly using a 4 foot loop with the SRF59.

1630    WRDW Augusta GA     1    05:35    30/03/2008    3788 miles    6096 km
1650    WHKT Portsmouth VA      1    05:32    30/03/2008    3399    5470
1670    WVVM Dry Branch, GA    1    05:37    30/03/2008    3887    6256
1680    WLAA Winter Garden, FL  1    05:40    30/03/2008    4019    6468
1620    WDHP Saint Croix USVI    1    06:10    02/04/2008    3931    6326
1700    WEUP Huntsville, AL    1    05:45    02/04/2008    3909    6292
1660    WFNA Charlotte NC    1    05:50    02/04/2008    3657    5885

I am fairly sure that I have had KVNS on 1700 Barefoot this would be 4794 miles but not willing to claim with no id - the station heard had oldies and KVNS is usually dominant here on this freq - amazing when you think they run 880 watts at night.

Hope these logs are of interest.

have you thought of a flea class for reception of 1 watters -  I have one at about 270 miles!.

regards for now

Paul Logan
Lisnaskea, N. Ireland.


bjohnorcas@... wrote:
Paul,

You might check the World Records at various transmitter powers. You might
be setting records for 50 kW stations, for instance. In any case, a great
set of loggings!

John Bryant



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20.25" Loopstick Successfully Tansplanted into SRF-39FP

Gary DeBock
 

Hello Guys,
 
     The fanatical mega-loopstick experimentation with the SRF-39FP has reached a new level (perhaps along with the eccentricity of the experimentor).
 
     Using two 7" and one 6.25" ferrite bars tightly taped together (then reinforced by thick rubber hose), a monster 20.25" ferrite bar was created, and an LCR meter was used to precisely adjust recycled coils to match the inductances on the stock 1.75" ferrite midget bar.  After full alignment, the resulting DX monster smoked a fully-aligned ICF-2010 on all frequencies in sensitivity, providing solid copy of signals at the 2010's noise level.  A fully-aligned ICF-S5W tried but failed to compete on the lower frequencies, then got smoked on the upper frequencies.
 
     Being fully aware that this experimentation has gone well past the point of reason, I think it's time to quit for a while, before the loopsticks fail to fit through a standard doorway.  A general article describing these experiments should be finished for dxer.ca shortly, but if any tinkerer desires specific instructions on how to create one of these DX monsters, please contact me, and specify the loopstick size planned (7", 14" or 20"). It is suggested that multiple SRF-39FP's be ordered off of eBay, if you have a risk of becoming a sensitivity fanatic (like yours truly).
 
                                                                              73,  Gary      




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Re: Off topic balun question

Paul Logan
 

Hi John,

Im familiar with your excellent articles on balun fabrication and in fact have been using them as a reference for ages.

I was just wondering what cores are used in commercial rx baluns which claim to cover long wave up through HF.

Any ideas anyone?.

bjohnorcas@... wrote:
Paul,

I'm outta town for the weekend and away from references. However, from
memory, there really isn't one formulation of ferrite that will work at
OPTIMALLY at Longwave up through 30 MHz. Generally, Bill Bowers and I shot
for really good performance from 5 MHz. down. The problem tends to be at
the lower frequencies, where performance can drop off like it was shot. My
impression is that upper frequency performance is much more forgiving.

I believe that there are two impedance matcher articles on dxing.info. Be
sure that you are reading the latter one, if you only read one.

John B.,



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Re: Loggings for 4/4/08

bjohnorcas@...
 

Paul,

You might check the World Records at various transmitter powers. You might
be setting records for 50 kW stations, for instance. In any case, a great
set of loggings!

John Bryant


Hi all,

a few TA's noted here on the SRF59 barefoot this morning -

850 WEEI
920 CJCH
940 CINW
950 CKNB
1010 CFRB
1010 WINS
1130 WBBR
1170 WWVA

When coupled to a 4 and 2 foot loop around dawn these and others were
pretty easy copy.

regards



Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
Photos: http://www.flickr.com/photos/radiofotos/
Video: http://www.youtube.com/user/yogi540
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Re: Off topic balun question

bjohnorcas@...
 

Paul,

I'm outta town for the weekend and away from references. However, from
memory, there really isn't one formulation of ferrite that will work at
OPTIMALLY at Longwave up through 30 MHz. Generally, Bill Bowers and I shot
for really good performance from 5 MHz. down. The problem tends to be at
the lower frequencies, where performance can drop off like it was shot. My
impression is that upper frequency performance is much more forgiving.

I believe that there are two impedance matcher articles on dxing.info. Be
sure that you are reading the latter one, if you only read one.

John B.,



Hi Paul:


Our own John Bryant wrote the book on these! Look to
www.dxing.info/equipment/impedance_matching_bryant.doc and
www.dxing.info/equipment/impedance_transformer_bryant2.doc
for the scoop on baluns

Kevin S.
Bainbridge Island, WA



Hi all,

I know this is off topic but was wondering can anyone suggest a suitable
ferrite core for general listening from long wave up to 30 mhz - does
such
a core exist?.

I found a T 200 - 2 in my junk box but when I worked out the turns
needed
to cover 1 - 30 mhz it was something crazy. Any suggestions for
something
useful for this one?.

regards




Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
Photos: http://www.flickr.com/photos/radiofotos/
Video: http://www.youtube.com/user/yogi540
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Re: Off topic balun question

satya@...
 

Hi Paul:

Our own John Bryant wrote the book on these! Look to
www.dxing.info/equipment/impedance_matching_bryant.doc and
www.dxing.info/equipment/impedance_transformer_bryant2.doc
for the scoop on baluns

Kevin S.
Bainbridge Island, WA

Hi all,

I know this is off topic but was wondering can anyone suggest a suitable
ferrite core for general listening from long wave up to 30 mhz - does such
a core exist?.

I found a T 200 - 2 in my junk box but when I worked out the turns needed
to cover 1 - 30 mhz it was something crazy. Any suggestions for something
useful for this one?.

regards




Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
Photos: http://www.flickr.com/photos/radiofotos/
Video: http://www.youtube.com/user/yogi540
Send instant messages to your online friends
http://uk.messenger.yahoo.com


Off topic balun question

Paul Logan
 

Hi all,

I know this is off topic but was wondering can anyone suggest a suitable ferrite core for general listening from long wave up to 30 mhz - does such a core exist?.

I found a  T 200 - 2 in my junk box but when I worked out the turns needed to cover 1 - 30 mhz it was something crazy. Any suggestions for something useful for this one?.

regards




Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
Photos: http://www.flickr.com/photos/radiofotos/
Video: http://www.youtube.com/user/yogi540

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Loggings for 4/4/08

Paul Logan
 


Hi all,

a few TA's noted here on the SRF59 barefoot this morning  -

850 WEEI
920 CJCH
940 CINW
950 CKNB
1010 CFRB
1010 WINS
1130 WBBR
1170 WWVA

When coupled to a 4 and 2 foot loop around dawn these and others were pretty easy copy.

regards



Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
Photos: http://www.flickr.com/photos/radiofotos/
Video: http://www.youtube.com/user/yogi540

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Gary's SRF-39 with the big loopstick

sloshatron <wa1gwh@...>
 

Hi Folks;

Very interesting antenna transplant that Gary performed on the SRF-
39. Any special reason that the coils are way out on the ends of the
ferrite bar? I presume the original antenna and the big transplant
needed the coils separated to allow movement for alignment.

The reason I ask is that on the crystal set discussion group that I
participate in, Ben Tongue (of Blonder-Tongue fame) has pointed us to
an article of his where he examines the efficient construction of
ferrite bar inductors. He has concluded that best performance occurs
with the coil centered and occupying no more than about 1/3 of the
bar's length.

I wonder if the total inductance required for an SRF radio could be
brought about with the two coils closer together and more or less
centered? Perhaps a few turns would have to be removed from one or
the other coil in order to counter any possible increase in total
inductance by having them closer together.

I can't see why an air core loop could not be used as a transplant
antenna. Except for the distributed capacity differences (and I'm
not sure how a ferrite inductor vs an air core one varies) I think
that an inductor is an inductor. The one difficulty I can think of
is how to tune the darn thing for alignment purposes. I guess you
could measure signal strength with a meter at the audio output, and
then remove turns as you go through the same alignment procedure as
with a ferrite bar. It would be a slower process and might involve
adding back fractional turns. The meter would enable the alignment
scheme to work in though you have to turn off the radio and remove
turns.

The reason I bring up air core loops is that crystal set
experimenter's have pointed out quite a bit of variability of
performance in ferrite bars. An air core loop would eliminate this
problem as well as finding a suitable bar.

I have copied Gil Stacy's idea of a variable capacitor and an
inductor as a booster antenna on my SRF-49. Except that I used a 4
1/2 inch air core coil of #21 wire basket wound (left over from a
crystal set project!). I gives a very prominent boost in
performance, so I presume one like it or bigger, of suitable
inductance, might work very well.

Comments?

Thank you,

Garry Nichols


Re: Gary's SRF-39 with the big loopstick

Gary DeBock
 

Hello Garry,
 
     Thanks for your comments on the SRF-39FP mega-antenna transplant, and welcome to the discussion.  The crystal set group and the ultralight radio group seem to have a lot in common (interest in maximum performance from minimal equipment), so we are especially happy to welcome enthusiasts from your side of the AM-DX hobby.
 
     My interest in huge transplanted loopsticks grew out of a fascination with the SRF-59's stock DX performance, with only the tiny 1.75" ferrite bar.  After receiving three TP's with this miniscule antenna, I began to seriously wonder what the amazing CXA1129 chip could do with a generous DX antenna, and whether such a combination would outperform the classic DX portables (ICF-2010, E1, ICF-S5W) in sensitivity.
 
     Alignment of about 25 SRF-59's (for myself and others) gave me a good idea of how the stock loopstick works, i.e. a fixed longer coil with a tap point, and a smaller, movable coil used for alignment.  Around February, in an experiment documented on dxer.ca., I transplanted my first 6.25" ferrite bar into an SRF-39FP "prison radio," which is basically an SRF-59 with a bigger tuning dial, and better components.  The first "Super Prison Radio" was constructed without an LCR meter, and essentially was an exact copy of the stock loopstick, although on a larger scale.  It had definite alignment peaks at 600 kHz and 1400 kHz, and had sensitivity roughly equal to the ICF-2010 (better on some frequencies, slightly worse on others).
 
     Using an accurate LCR meter, further experiments were conducted on three other (6.25" and 7") loopsticks,  using recycled coils with inductances carefully matched to the stock coils.  After careful alignment, these units had sensitivity generally superior to the ICF-2010 on all frequencies.  They deadlocked with the ICF-S5W on the lower and middle frequencies, but these "SPR2" units were more sensitive on the high end than the S5W.
 
     The recent experiment, using two 7.25" ferrite bars tightly taped together, resulted in an "SPR3" unit with a total antenna length of 14.5", and sensitivity clearly superior to any stock portable on every frequency.  Concerning the separation of the larger and smaller coils on the loopstick, Garry, this was primarily a convenience for construction, since the loopstick mounting post is attached to the center of the loopstick for secure mounting, and also the smaller coil needs about 2" of space to find the 600 KHz alignment peak, even after the optimum inductance of .598 mh is obtained across both coils. 
 
     Concerning  Ben Tongue's impression that ferrite bar loopsticks have the best performance when the coils are centered (and occupying no more than 30% of the bar's length),  I have constructed SRF-39FP loopstick transplants where the both coils were near the center, and found performance identical to the "separated" orientation.  We must remember that Sony engineered the SRF-59/39 loopstick with separated coils (presumably for alignment), and that the stock loopstick has fantastic DX performance for its size, in the "separated" orientation.  If a hobbyist wished to have both coils near the center of the bar, he would have a tricky alignment process, and would also need to construct a support framework that avoided the coils (making the support look something like a slingshot).  IMHO, such additional hassle wouldn't give any real DX improvement, Garry.  Thanks again for your interest in the mega-transplant!
 
                                                                                                     73,  Gary DeBock    
 
      




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Greetings from Joe Miller, KJ8O

radiodxer2000 <radiodxer2000@...>
 

Hello everyone,

Today is the second anniversary of passing my first amateur radio exam
so I thought it would be a great day to joing this list as well. Not
too much planned for this weekend, but am going to try for the CBA
Moncton DX Test using both Sonys, the SRF-59 and the ICF-2010. Maybe
they will send 2 QSLs, hi hi hi.

Congrats on #450 Rob, that's more than what I've ever done in my noise
infected QTH with my 2010.

See you all later...

Joe


Off to see the Wizard.......with a Bag of ULR's under my arm!!

robert ross
 

Hi Guys:

Well.......I'm off to the Semi-Annual ODXA DX Camp in the
morning.........will be there til Sunday afternoon. It is held North of
Toronto....so we're a Long Way from any Ocean ....but there is a Tiny
Little Lake located at the camp.......Musselman Lake...I think it's named
after all the He-Men that go to the DX Camp!! HAHAHHAHA.......

Saul Chernos and Niel Wolfish from Toronto are also going to be in
attendance.....so we'll have good ULR DX'er Presence there.

I have a Bag of ULR's all packed and ready to go.........2 Sony SRF-39's, 2
SRF-59's, a Sony SRF-T615, and an ETON E-100........all aligned by Gary
Debock to assure Maximum DX Potential!!!

Now we just have to pray to the DX Gods for good conditions....and LOW
Noise Levels!!

I'm also taking a DRAKE R8B along......just in case .......or I decide to
do some Short Wave DX'ing.

Anyways.....I have enough ULR's to give everyone in attendance a chance to
try them out.......so we may be able to get a few more ULR ADDICTS signed
up for the 12 Step program!! HAHHAHA.....

We'll let everyone know how we do when we get back. This is always a lot of
fun....10 or 12 Crazy Buggers all squashed into a single room with a
Million Radios.........and a few Cases of Beer!!! With those
armaments.......anything should be possible....

Wish us luck!!

73.....ROB.

Robert S. Ross VA3SW
Box 1003, Stn. B.
London, Ontario
CANADA N6A5K1

Antique/Vintage Radio Enthusiast
Amateur Radio Stations VA3SW/VE3JFC

Defy Physics.....Play Table Tennis!! (Ping Pong with an Attitude)
«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»¥«¤»§«¤»¥«


SRF-59 coupled to ferrite bars

lrdheat
 

Dear folks,

Gary's mating of a large ferrite bar to the SRF-59 would be highly
desirable. Like another earlier post, I shy away from opening radios
as "disaster would be sure to follw". I am including a part of a note
that I sent to Gary describing my experience today with inductively
coupling the SRF-59 to a couple of radios with large ferrite bars.
There are some nice pluses to using a radio as opposed to tunable
ferrite bars or selectattena types(sp?)in that the tuning display of
the radio will provide an excellent indication as to what frequency
the ferrite bar is tuned to!

I found today that the coupling my SRF-59 with the antenna in either a
SANGEAN PR-D5, or with a SONY ICF-EX5 makes the SRF-59 slightly more
sensitive than either set. The PR-D5 has to be on for this coupling to
work. That is good and bad...it means that I am using the PR-D5's
batteries during a dxing session, but it also means that it is easy to
properly tune the PR-D5's antenna to the frequency that I hope to peak
on the SRF-59!. The coupling has a very sharp null, and a fairly
narrow peaking window...just offtuning 10 KHz is noticable, and an
offset of 20 KHz is quite noticable. In the case of the analog SONY
ICF-EX5, the EX-5 need not be on...tuning the sliderule indicator to
the frequency of interest results in a pronounced peaking of the
signal on the SRF-59 with about as much of a boost as produced with
the PR-D5.

The attraction of your experimental homebrews is that it does not
employ two items that need to be tuned for each frequency of interest,
and that it is much more portable, has a much smaller footprint.

I'm back...this is a neat refreshing change from the swl'ing that I
had been doing, and harkens back to my days as a youngster staying up
to all hours of the night listening to dx on a 6 transistor set using
the radiator in my room as an antenna.

What type of tips might you have for trying to catch trans Atlantic dx
from Laredo, TX?

Heatwave


Re: SRF-59 coupled to ferrite bars

Gary DeBock
 

Hello Richard,
 
     Thanks for your comments, and the information on your SRF-59 inductive coupling with the PR-D5 and ICF-EX5.  Your approach is one that's new to me, although booster bars (such as the excellent units kindly made and given by Gil Stacy and Kevin Schanilec) are heavily used here, and most of the TP's I logged on the ICF-2010 last fall were inductively coupled from the Quantum Loop 2.0+, which of course required tuning twice.
 
     The loopstick transplants, especially the latest (SPR2 7.25" and SPR3 14.5") experiments, generally boost the SRF-39FP sensitivity past the ICF-2010 stock level, but not past the 2010 + Quantum Loop level. The 2010 + Quantum Loop is a very effective combination, although it does require tuning twice. It would be like a dream to construct a stand-alone modified Ultralight, with the same sensitivity as the 2010 + QL combination.  I think it's possible, but the loopstick may not fit through a standard doorway  :>)
 
     Loopstick transplant science has had a tremendous boost because of the Ultralight phenomena, but these improvements are not limited to Ultralights.  It would now be routine to give radios like the ICF-2010 and ICF-SW7600GR larger, more effective antennas, assuming the owner could live with an external mounting system.  My own impression is that an ICF-2010 with a 14" loopstick could outperform a 2010 + QL combination, but we will never know for sure until somebody actually tries it. 
 
     Thanks again for your comments, Heatwave, and the "Super Prison Radio 2" article should be finished soon, giving everyone detailed instructions on making this DX dynamo from a commonly-available 7.25" loopstick. 
 
                                                                                                              73,  Gary  




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Re: Just Joined

John H. Bryant <bjohnorcas@...>
 

Kirk,

Welcome to ultralightdx!  You mentioned needing a comprehensive list of broadcast band stations.... I'd been meaning to write to you about that.  My favorite web site is http://topazdesigns.com/ambc/  THat is a two part site.... on the right-hand side, you can search a particular frequency for call letters (including a nice "fuzzy search" feature) or you can search a particular frequency by format of the broadcast.  On the left-hand side, you can put your home geo coordinates into the blanks (just have to enter once) and then type in the call letters.... searches every frequency for the station, gives you all sorts of info on the station and the distance from you to them, etc.

Another good one is http://www.radio-locator.com/

A third one that is a more conventional listing, and very good, is http://www.amlogbook.com/

Then you have to start looking for individual countries.  You can google Fred Cantu's site for Mexicans and Bruce Conti has an EXCELLENT Cuban list.

There may be other resources out there that other members could suggest. Perhaps we should put these things in the Links section of our website.  I know that there are some amateur radio operators interested in ultralighting and they are probably like Kirk.... relying on memories that are 20 or 30 years old, as far as BCB DXing is concerned.

Anyone else out there with suggestions?

John B.


At 08:22 PM 3/31/2008 +0000, you wrote:

Hi Everyone,

I just joined this group thanks to info from my old friend, John Bryant. I'm very new to this aspect of MW DX'ing. Also tnx to John, I'm using an SRF-59. Due to time constraints during the night and early mornings, I've only just begun, but looking forward to many more hours of fun with this. I'm an old (literally)  DX'er starting in the early 1980's but mainly on the HF bands. I've not heard any station that's considered outstanding yet. Have only hrd one XE that I could ID on 850 kHz-XEM, R. Exitos, but have heard a few domestic stations that I  don't believe I've ever logged before (but my memory for MW is rather faint.) I intend on finding a comprehensive listing of MW stations asap. Any suggestions? Greeting to all and 73!

Kirk Allen

kirk74601@...

Ponca City, OK

 

 















John B.
Stillwater, Oklahoma, USA
Rcvrs: WiNRADiO 313e, Eton e1, NRD-535(kiwa-mods)
Antennas: 700' NE/SW mini-Bev, Wellbrook Phased Array (pre-production version)


Re: "March Madness" Project-- A 14.5 inch Loopstick Transplant for the SRF-39FP

John H. Bryant <bjohnorcas@...>
 

Gary!

Great transplant operation!!!  Several questions:

1. Where did you get the Litz wire that you are using to wind the coils?  What size is it?

2. Are you following the L values from that one-page paper of the Bryant/Hall-Patch tests of the SRF-39FP ferrite antenna (in our Files section)?? If you are, are you still getting great results "right out of the box" using those "L" values to wind the coils???

3. What determines the distance between the ferrite new bar and the top of the SRF-39??

4. Have you tried running the connecting wires parallel to the bar (as they run in the stock unit) and then vertically down the ruler, rather than diagonally?  Is their a measurable loss?

A couple of suggestions for further experimentation: When Bill Bowers and I were building the 8'-0" Monster Ferrite bar antenna, Bill did a good bit of careful experimentation with the 3/4" x 12" bars from which the Monster was constructed. He found that there was a significant reduction in gain if the butt ends of the bars were not PERFECTLY flat together.  He proved that finding in the field when our 4"x 4" redwood support beam under the bundle of ferrite bars started sagging (yes!) That slight sag plus changes in temperature (the Monster was mounted outside) opened up tiny wedge-shaped spaces between the flat bar ends and there was quite a loss of gain. Bill ended up putting a cap over each end of the monster and then putting bolts in threaded holes in the caps to put each line of ferrite bars in serious compression. In your photos, it appears that the two bars are sagging a bit.  Maybe the ends that you are working with are not perfectly square and you are getting good contact, despite the apparent sag.

Another thing that Bill learned is that even with perfect contact between the ends of two bars, laying in a third bar that overlaps the joint of the first two by at least 1/3 of its length made a very measurable increase in gain.... more than could be accounted for just by the additional mass of ferrite.  So, you might want to try adding a third bar in close contact with and overlapping the first two..... sort of magnetically reinforcing that center joint.... I wonder if you would increase gain even further???

In the third bar approach, Bill said that it was as if the magnetic lines of force flowed through that third bar, bypassing the joint between the first two.... might be worth a try?

Anyway, Gary, great transplant operation.... let us know how it goes at Grayland!
 

John B.
Stillwater, Oklahoma, USA
Rcvrs: WiNRADiO 313e, Eton e1, NRD-535(kiwa-mods)
Antennas: 700' NE/SW mini-Bev, Wellbrook Phased Array (pre-production version)



At 10:25 PM 3/31/2008 -0400, you wrote:

Hello Guys,
 
     Welcome to all ultralight DX enthusiasts!  We are all especially happy to have a growing ULR fan base in Europe and South America, and feel honored to have you as part of our enthusiastic team.
 
     In search of the ultimate DX portable, a 14.5" loopstick was successfully transplanted into an SRF-39FP "Prison Radio," by use of an LCR meter, and two 7.25" ferrite bars tightly wound with heavy-duty tape.  After full alignment, the sensitivity apparently exceeds any stock portable in sight (ICF-2010, E1, ICF-S5W, etc.).
The most exciting point is that the loopstick was constructed of readily available parts, and the entire experiment cost less than $60 US.  A full article on this "Super Prison Radio 3" will be available shortly, documenting all the steps and part sources.
 
     Three photos of this DX Monster have been uploaded to the Ultralightdx Yahoo Group site, and it is rumored that this ultimate Ultralight may soon haunt the shores of Grayland, Washington.  This radio is so much DX fun, it should be illegal!
 
                                                                                        73,  Gary DeBock




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