[R-390] IF Alignment Question

[Flowertime01 at wmconnect.com]

Barry,

You are OK. PANIC NOT
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I noticed that when I switched slowly from band 0 to band 1, the diode load 
would increase a bit before clicking to the next band. 

???
This is your first clue that you need to pull the RF deck someday and do a 
visual alignment of the RF band switch.

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I noticed the rack that was moving the most at that point was the second IF.

Leaving the radio set to a BC station, I started playing with the slugs in
the IF and noticed a dramatic improvement in signal strength.  I peaked all
six coils that way and the radio seems to be a lot more sensitive.

Am I doing the alignment a disservice to peak the IF coils this way?  Does
this set them at an optimal position for one part of the band and reception
will suffer at other portions of the band?  That didn't seem to be the case
but I didn't test it all that much.

???
Barry,

I was common shop practice to align the variable IF slugs and caps by running 
a signal into the antenna inputs and catching the slugs and caps as you were 
doing the RF octaves.

1.000     use 1.100
1.250     use 1.100
1.900     use 1.900
7.250     use 7.600

Or as you are doing the RF octaves readjust the setup to the frequencies as 
given in the TM and do the variable RF alignment. Use the same signal generator 
output as you use for the RF octaves ( < 10 uv )

Your right this gives much better tracking, gain and signal to noise 
performance.
By doing the alignment this way you are dialing in the same PTO and crystal 
mixer offsets as the receiver really has.
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When I said I followed the instructions, I don't have the "Test Lead 
CX-2919/U" the instructions call for.  I was just connecting the output of the 
generator directly to the test points and using a minimum signal, did the 
adjustments.  

Is this possibly causing the circuit(s) to be loaded improperly and detuned? 
???
no and no
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 Does anyone know what's in that Test Lead?

???

yes a 0.01 cap In case you poke the lead into a point with B+. The "adapter " 
was used in a lot of places. We used a length of coax with a cap soldered on 
the center conductor. We depended on the receiver ground strap for a return 
path. We used the cap with a bare lead so we could bend a hook on it and hang 
it. Or we used the lead wire straight. Once the lead broke off to short from 
many bending we just soldered a new cap on the coax.
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By the way, I'm using a GR-1001A generator with the 50-ohm impedence adapter
and an HP-410B meter.

???

Nice bench.

Roger AI4NI