= = = (bpnjensen) wrote in message
= = = . com...
(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...

BJ,

YES - I DID NOT KNOW - I think that sometimes you just get 'lucky' )

READ: Assessing unknown Ferrite Toroids
http://www.alan.melia.btinternet.co.uk/toroids.htm

As for Me the whole "ART" and 'science' {mystery] of SWL Antennas is:
* Read & Think
* Build & Do
* Surprise & Enjoy

Afer all, I am simply a SWL and Not On A Power Trip ~ RHF
{ No Transmitter Required }
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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?


I bought the ICE 180A and it seems to work very well down through
the AM/MW Broadcast Band (500 kHz) although it's listed Coverage
is 1.5 MHz to 30 MHz. The ICE 182A Beverage Matching (Isolation)
Unit has a listed Coverage of 100 kHz to 30 MHz.
http://www.arraysolutions.com/Produc...age%20Matching

As to the Debate about what makes an ICE 180A and an ICE 182A 'different':

"IDK" - I DON'T KNOW ! {Did 'mister-know-it-all' Really Say "IDK" }
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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.

Concerning the 'topic' of Binocular Core Matching Transformers
her are a several Links/URLs to take-a-look at:
* Multi-Aperture Cores
http://partsandkits.com/binocular.html
http://www.cwsbytemark.com/CatalogSh...Files/2_34.pdf
* Wide Band RF Transformers
http://www.electronics-tutorials.com...ansformers.htm
* * What are Toroids ?
http://www.electronics-tutorials.com/basics/toroids.htm
* RF Transformer - Mini-Circuits
http://rust.lbl.gov/~gtp/DOM/dataShe.../tranfrmr.html
* Inductors: Binocular Balun Cores - Surplus Sales
http://www.surplussales.com/FerMisc/FerMisc-5.html
* Construction and Use of Broad Band Transformers - Figuer #2
http://www.oselectronics.com/downloa...ansformers.pdf
* Amidon #43 & #61 Material Two-Hole or Binocular Cores
http://www.amidoncorp.com/aai_woundbeads.htm
* Impedance Matching Transformers for Receiving Antennas
at Medium and Lower Shortwave Frequencies
Bill Bowers - John Bryant - Nick Hall-Patch [VE7DXR]
http://www.dxing.info/equipment/impe...ing_bryant.doc
http://www.dxing.info/equipment/impe...mer_bryant.doc
* Baluns - Kits & Custom - The WireMan
http://thewireman.com/baluns.html
* Baluns in Theory - RadioWorks
http://radioworks.com/nbalun.html
* Toroidal Balun Kits, Toroids and Enamelled Wire Packs - OZ-Gear
http://www.ozgear.com.au/balun/ToroidalBalunKits.htm
* Balun and Transformer Core Selection - Binocular Core Image
http://www.w8ji.com/core_selection.htm
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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


iane ~ RHF
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