[R-390] Below 8mhz problem

[blw]

Jim,

I'm hoping you keep us up to date with what you find out. I have a EAC that
has the same problems you describe. I'm going to get to it one day and will
have to go through this too.


Barry


> Hello to the list,
> 
> As an update, I have found that E209, before the 1st mixer has low voltage.
> It should be approx -6.5 volts, and it actually is -.85.  Measured with a
> 1meg resistor it is -.76.
> 
> The other RF deck test points have good voltage.
> 
> The faint cal signal below 8mhz is the same on all bands below 8mhz.  This
> prevents me from hearing the signal generator signal needed to calibrate the
> variable IF section.  The cal signal on all bands 8mhz and above is strong
> and loud.
> 
> I have received suggestions to:
> 
> 1.  Check all the appropriate coils, switches, antenna relay, and anything
> that plugs in or wipes, before the 1st mixer v202, due to corrosion
> suspicions because of the "massacre" origion of the radio.
> 
> 2.  Check HR202 crystals, especially 17mhz.
> 
> 3.  Inspect circuitry between 1st mixer V202 and 1st crystal oscillator
> v207.
> 
> The crystal seems to be OK, because I purchased a spare HR202 with the
> radio.
> 
> I have substituted the 6c4 and 5654 tubes V202 and V207 with no change.
> 
> Thanks for the suggestions, and tomorrow I will get deeply into the above
> suggestions.  So long for now.
> 
> Regards,
> 
> Jim
> 73, KF4ICZ