(RHF) wrote in message m...

Good information snipped

STARMAN,

Isn't Type 43 the recommended as a Balun "Core Material" ?

Why isn't Type 61 also a 'suggested' Balun Core Material ?

NOTE: Matching Transformer = Balun = UnUn

True Story: A while back I bought a Grab Bag of Feritte Cores on eBay.
Some of them had a #20 Enameled Wire wrapped on them with 36 Turns.
They were about 1" OD x 1/2" ID x 1/2" H. So I thought, why not
try them as an Matching Transformer on an 'old' Telephone Two Wire
Service Line (pre-1950s) that runs overhead about 75 Ft from
the Power Pole to the House. Being lazy I simply wrapped a Twelve
Turn (12T) Secondary and wired it up with a #22 Magnet Wire from a
RadioShack 'three pack' Catalog # 278-1345 ($5). Well 36:12 Turns
worked good for AM/MW and up to 7 MHz but the Signal Levels fell
off after 7 MHz. So then I tried Reducing the Primary to 30
Turns and the Secondary to 10 Turns. Again the AM/MW Band was
good and the Shortwave coverage went up to 23 MHz. Not being
one to settle for 'good enough'; I then tried Reducing the Primary
to 24 Turns and the Secondary to 8 Turns. Well the AM/MW Reception
went down and the Shortwave Bands reception picked up to the CB Band.
So it seems that the 'majic' 30 Turns and 10 Turns worked the best
for my needs using this ?Core?.

RHF - it sounds like you did not know what the material for this core
was (43 vs. 61 or other) - right? Is it possible that the frequency
range is more dependent on the number of turns (inductance?) than the
actual material? This is not a trick question...

TESTING: The receiver for this Test was an Icom IC-R75.
http://www.icomamerica.com/products/receivers/r75/
My Matching Transformer "Test Standard" was an ICE 180A.
http://www.arraysolutions.com/Produc...age%20Matching
My Test Measurement were with "My Ears" and 'My Eyes' (S-Meter).
The 'old' Telephone Service Line was a Two Wire (Copper Clad
Steel?) Cable. One Wire was used for the ICE 180A and the
other Wire was used for the ?Core? Matching Transformer.

Question - what is the advantage of using the ICE 180A (1.5-30 MHz)
over the 180C (0.1 - 30 MHz)? Is the 180A inherently better suited to
SW because it does not need to be so broadbanded? Or will the other
work as well, PLUS get you MW? Do these use binocular cores? Or just
one of them?

FWIW: Reading your statement about the Binocular Cores, I
have just ordered some from Universal-Radio.Com to Test.
It is my understanding that One Turn 'counts' for Two when
You use a Binocular Core. Now Is That True ?

I would love to know this also, and also see a GOOD diagram of how to
wire a binocular core.

Also, I have a SWL 10:1 Balun that is made by "RF Junkie"
and will be testing it soon using the same test-set-up.
* Two Shortwave Listener (SWL) 10:1 Baluns for Random Wire Antennas
http://groups.yahoo.com/group/Shortw...a/message/1523

It is great to see all these fine antenna posts - becoming familiar
with the experience of others, and ultimately (hopefully) contributing
something that may help others, is the best and highest use of this
medium, I think (oh, yeah, that and name-calling over politics ;-)

Bruce Jensen