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

Send instant messages to your online friends http://uk.messenger.yahoo.com


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


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
Send instant messages to your online friends
http://uk.messenger.yahoo.com


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.,



Send instant messages to your online friends http://uk.messenger.yahoo.com