[R-390] UnBal for R-390A

[Flowertime01 at wmconnect.com]

Tisha,

Bob, makes a good point here about what the receiver gets peaked to depending 
on how you hook the signal generator to the receiver.

Most of the time we do not really care what the signal generator level is.
We just couple the generator to the receiver and hang a meter on the output.
Then we tweak whatever for the highest meter level.

If you have some matching device out front of the receiver then we want it in 
place and we want to couple the signal generator through it to the receiver.

Use what ever signal level you need, Just hang the signal generator to the 
antenna with a small 1,000 - 100 pf CAP. Then trim up the RF input transformers 
to get the most signal into the receiver.

This will at least get you the best match between the antenna you have and 
your receiver through the coupling circuit you are using.

Roger AI4NI


> Tisha,
> 
> Stick with your un-bal methodology.  This uses the best of the input 
> circuitry.  There is ONE other aspect to consider.  When performing an 
> alignment with a sig gen, the sig gen's impedance is what you will have 
> peaked the input for.  So it "may" turn out that the 120 ohm figure is 
> not the best.  Use the balanced input, but make your un-bal to match the 
> sig gen's impedance.
> 
> My $0.02 worth, and worth every bit of it!
> 
> Bob - N0DGN
> 
> Tisha Hayes wrote:
> 


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