Drake R4B alignment question
Ian King wrote:
The sensitivity is terrible, so I'm trying to align the radio and see if it
becomes acceptable. Problem is this: I'm injecting a signal as instructed
in the alignment instructions and attempting to peak T7 and T10 - with no
results. I'm hearing a signal, but from lock to lock on the transformers,
there's no peak (or dip). I have the AVC set to 'fast' (per the manual).
Any suggestions, anyone? TIA -- Ian
Hmmm, in the manual they say it will be broad...
Here's a thought. Since both coils exhibit this symptom and the set
still works to some degree, my thought is that you're not hitting on
50kc. To align the these 50kc coils they are having you inject a 5645
kc signal further upstream. The 50kc product is reliant on the 5595
xtal oscillator plus the 5645 signal from the generator.
If your generator was in fact putting out at say 5640 it would fall out
of the design range of these adjustments but you would still hear it and
probably get a meter deflection.
I'd suggest verifying that these two freqs are correct. This is why
they are insisting in the instructions that you listen for zero beat
which again requires that the calibrator and 50kc osc be properly
aligned first if I follow their logic correctly.
They wrote the alignment instructions with the assumption that a guy
would not have a sig gen that goes as low as 50kc. Do you have access
to one? That would take some of the variables out of the process.
Also make sure the notch filter is sufficiently detuned so as not to be
a player in the process.
GL,
Bill
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