{Collins} Re: 75A-2 No Receive



It was very common to add a product detector to the A2's and 3's NBFM 
socket.
That might be it......
Check the oscillators for output and signal trace/inject to find the bad 
stage(s)

Jim


> Just picked up an A-2.   Cosmetically very good, but it does not receive.
> Someone has added another 6BA6 in the NBFM adapter socket and a 455 IF can 
> under
> the chassis.  Not sure if this is a home brew NBFM unit or not.  Could not
> find any articles with a schematic that looks like this modification. 
> Would
> appreciate any inputs/suggestions if you know of this mod.
> In any event, the receiver has some noise on all bands in CW position, but 
> no
> stations.  Same symptoms on all bands.  Hooking up/discommencting antenna
> makes no difference.  No change twisting the trimmer.  BFO seems to work 
> because
> you can hear a change in the sound.  Very little--or no--noise in AM.
>
> Deoxited it, and checked all tubes.
>
> Any thoughts on what to check out?
>
> Thanks.
>
> Buck  W0RST

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