[MRCA] R-390A query

[DSP3]

Dale,

Your diagnosis was correct. One particular slug rack was NOT moving, 
indeed the one affecting the 4 thru 7 MHz bands.  The coupling is loose 
(hence no coil rack movement) but the cam is moving around correctly.  
In reading the TM, it says to set the cam follower so that it is not 
quire bottomed out on the cam at the lower frequency of the given band.  
I'm trying to divine which side of the cam "bottom" is the correct one 
and exactly where "up" on the can is the point "not quite bottomed 
out"?  I'm going to read the books again and see if I can glean the 
process better.  I can certainly gain access to everything necessary to 
affect the setup.  Its just knowing the exact point as to where on the 
cam I need to be.  Looks like this issue is indeed fixable!  The S-meter 
issue is progressing.

Jeep - K3HVG

On 4/27/2016 5:28 PM, Dale Gagnon wrote:
> Jeep.
> One thing you can do is operate the band switch on the bands that are 
> a problem and confirm that some cores are moving in and out of some of 
> the coil forms.  If you don’t see a rack of cores moving then look at 
> the gear trains behind the front panel and see if you have gear clamp 
> that is broken.
> Dale
> *From:* DSP3 <mailto:jeepp at comcast.net>
> *Sent:* Wednesday, April 27, 2016 5:02 PM
> *To:* MRCA at mailman.qth.net <mailto:MRCA at mailman.qth.net>
> *Subject:* [MRCA] R-390A query
> Gentlemen,
>
> I just acquired an EAC R-390A.  Its condition is rather amazing, 
> physically.  Before powering up, I replaced the DC blocking cap for 
> the filters.  In firing it up, I find two defects.  First of all, the 
> S-meter is apparently bad.  Subbing a 500ua movement, I can get 
> readings indicative of varying signal levels, albeit all in the lower 
> half of the meter scale.  What is the correct movement?  The second, 
> and perhaps more difficult issue is that the 4, 5, 6, and 7 MHz bands 
> are all but inoperative.  "Working" the bandswitch does not help. All 
> other bands appear normal. The IF chain is working OK and I can hear 
> very low level level signals from the calibrator when the BFO is on.  
> Beyond that, nada.  I have not put it on the bench to characterize 
> sensitivity, etc. but though I'd ask the group about the drop of these 
> 4 bands.  I know that each band has its own het crystal, but what are 
> the chances of 4 being bad and stacked in the same area?  Any hints 
> would be appreciated.  If someone has been there and done that, no 
> need to re-invent the wheel.....Hi!!!
>
> PS  I do have the proper manual.
>
> Jeep - K3HVG
>
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