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Old August 5th 03, 07:32 AM
Gregg
 
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Behold, Warpcore flashed in code from a keyed 4-1000A filament:

How 'bout I connect one line to the sheilding on the coax, and one line
to the center conductor of the coax - is that considered balanced, or do
i need something between the receiver and the antenna line to create a
balanced connection ?


Nope, not balanced. You should use a proper balanced line/antenna for best
results. You can use a BALUN between the coax and balanced inputs of your
RX.

TV types are 4:1 and the quality types can be used down to 5 MHz, with the
typical RS things good down to 15 MHz.

A 1:1 balun is probably your best option. You can wind your own (se ARRL
Radio Amateur's Handbooks) or purchase one called a "W2AU" balun, but
they're big. Only about $20 though. They are good from 160 to 6M.

I hope you don't mind my asking questions about these fundamentals. If
there is a website to explain in simple terms, taht would save you the
effort of typing s. I DO appreciate the response.


Typical balanced antennas are the dipole (folded full-wave [300 ohm] and
1/2 wave [72 ohm]), quad, delta and other loops. Unbalanced types are like
end-fed anything (longwires), J-poles, 1/4 wave verticals, etc.

An antenna will give proper performance if it's tuned to the lowest
frequency you expect to receive. For a 1/2 wave antenna, like a dipole,
the length should be:

Lmetres=150/fMHz

If you have limited property, you can helically wind it on a form.

For unbalanced antennas, a good ground is neccessary. Cold water pipes
are OK, but a counterpoise is better.

Balanced antennas are relatively independent of a ground, but the RX
equipment should be grounded for reduced noise and safety.

Hope this helps.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
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