HW-101 Audio Amp Questions/Problems

[Jim Flanagan]

I own two HW101s with **vastly** different audio gains, yet I have 
checked all the voltages and resistances
as well as the power amp tube, V14 and cannot find any problem ( I ended 
up changing that 22K
resistor and the 22uF cap).  I am seeing a 20dB voltage gain difference 
in the final power amp stage between
the two radios.  What I would like to know is, what is the correct audio 
gain that the system is designed for?

The triode stages of the two radios appear to have an identical gain of 
about 26-30dB (voltage gain @ 1Khz test freq)
The pentode stage of one radio is 10dB, whereas the other is about 30dB.

I am beginning to suspect the output transformer.  I did some quick 
tests and could verify that the
prim/sec  turns ratio appears to be about 40  for the low z winding.  
Does anyone know what the  specifications
should be for the output transformer?   I have a spare transformer that 
is slated to go into a SB-102 restoration and
the primary resistance shows to be about 211 ohms.  This agrees with the 
transformer from the HW101 with
the abundance of audio gain.  However, the 101 with the low gain shows 
the primary DC resistance to be 150 ohms...
The output transformer may be bad, but I am not sure.  I think I may 
need to remove the transformer for further
testing.

Anyway, your help is appreciated.  Is their any reference audio 
amplitude levels that I could check my testing with?

Thanks..
Jim

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