Date   

Re: fanatical mega-loopstick question

Guy Atkins
 

Hi Garry,

I had been thinking about spider coils also for an ultralight. How large of a coil form do you think would be needed to compete with a hot rodded ferrite loop? Also, do you envision concentric coils on the form separated by a distance or one continuous coil with tap points as needed?

Guy Atkins
Puyallup, WA USA
www.perseus-sdr.blogspot.com

Sent via BlackBerry from T-Mobile

-----Original Message-----
From: "sloshatron" <wa1gwh@twcny.rr.com>

Date: Sat, 05 Apr 2008 22:58:16
To:ultralightdx@yahoogroups.com
Subject: [ultralightdx] fanatical mega-loopstick question


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: Argentina on 1620

huelbe_garcia@...
 

Hi Paul,
 
can you describe what kind of programming you heard? If we can confirm that, it's a nice DX!
 
I live next to Argetina (south Brazil) and there is an station on 1620 really strong. I learnt it relays an FM and programming and is basically popular rock music from 70s to 90s. It is called "Universo".
 
This station is located in Mar Del Plata, Argentina.
 
Huelbe
Porto Alegre, Brazil
 
 

----- Original Message -----
From: Paul Logan
Sent: Saturday, April 05, 2008 11:00 PM
Subject: [ultralightdx] Argentina on 1620

Hey All,

which Argentine station on 1620 really "gets out" weak on the srf59 with a one two foot loop.


Paul Logan,
Lisnaskea, N. Ireland

Listening Homepage: http://geocities.com/yogi540/
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Video: http://www.youtube.com/user/yogi540

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Re: Argentina on 1620

Paul Logan
 

One of these days I will manage English! that was supposed to read " with a two foot loop"

Paul Logan wrote:
Hey All,

which Argentine station on 1620 really "gets out" weak on the srf59 with a one two foot loop.


Paul Logan,
Lisnaskea, N. Ireland



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Argentina on 1620

Paul Logan
 

Hey All,

which Argentine station on 1620 really "gets out" weak on the srf59 with a one two foot loop.


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: fanatical mega-loopstick question

Gary DeBock
 

Garry and Guy,
 
     All of the mega-loopsticks (7", 14" and 21") have been constructed using an LCR meter to measure inductance only, to ensure that the recycled coils (mostly salvaged from the vintage long ferrite bars) match the  SRF-39 stock coils in inductance.  The alignment procedure, in which the small coil is slid along the ferrite bar to peak a low-band (usually 600 kHz) signal,  optimizes the match between the recycled coils and the SRF-39 circuitry, making it unnecessary to measure capacitance and resistance during the construction process.  As long as the inductances match, and the 600 kHz peak is sharp, the newly recylced coils are perfect for DX reception in the SRF-59.
     As for comparison of the ferrite mega-loopsticks and  spider coils, I'm sorry that I have never experimented with spider coils, or air-core loops.  The ferrite mega-loopsticks seem to be great for DX, relatively cheap, and still quite portable.  The only drawback is that you inevitably make longer and longer ones, as you fanatically strive for the highest sensitivity level.  Eventually you need to face the reality that doorways are only 30" wide.
     Guy, if you wish to make some spider coils and compare them to the mega-loopsticks, you can borrow them at any time (Guy and I live in the same city).  As of today, all of them will still fit through a doorway  :>)
 
                                                                                           73,  Gary
    
   




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Re: Calling John Bryant / Firsts and distance records

Paul Logan
 

Hi Dennis,

I have two SRF59's one was tweaked by me - as it turns out the tweak brought radio # 2 up to the level of the other stock one in terms of sensitivity so I may have got a "dud".

However I did get the 2nd radio to tune the x- band which the stock Euro versions dont cover.

All of the TA signals outside the x band were heard completely barefoot -  x band catches were made by placing the radio inside a 4 foot loop.

Great little radio - Im also very taken with its audio - I often hear WLAA 1680 and the Mexican music sounds superb.

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

73



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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/
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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/
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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
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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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