HW-16 Receive problems

[Mike Souhrada]

KARL ECKERLE wrote:
>
> To all you greenies, I am referbushing an HW16 and have run into a
> problem.  The transmitt is ok, but the receive is not.  The expected
> receiver noise (with out antenna attached) is not present.  I have have
> checked the audio output stages by toughing the input grids of v6a and
> v6b.  They are ok. The heterodyne oscillator is working on all three
> bands, I can hear the oscillator a receiver tuned to each of the three
> crystal frequencies. Coils l4, l5, and l6 have all been peeked.  All
> voltages have been checked and the only voltage that dosen't agree with
> the schematic is at v3b, the v.f.o. tube.  Receive voltage at pin 8
> should be 4.5, it measures 4.9 which is ok, however at pin 9, the
> receive voltage should read a -.75, it reades same as pin 9, 4.9.  I.ve
> checked all the components associated with v3b.  l7, the v.f.o. coil
> checks ok, about 2.4 ohms.  The parts and wiring are correct.  I touched
> a screw driver to cap c66 which is a coupling cap (.005mf) form the half
> crystal latis filter to the input grid of if amplifier v4 and got a very
> week local am station.  Turning the v.f.o. dial has no effect.  Any
> suggestions?
>
>Karl
I've had 15 of those and every one is a new "challenge" HI!
That VFO tube I suspect has an error on the voltages-belive its' the
input
pin #2-never have had one right yet.

As for your problem can only suggest you look at the QSK circuit- that's
built around the NE bulb in the rear. Common problem area- also check
the
transister up front right hand side of the PCB. Believe that's also part
of the switching circuit.
Only other thought is miswired on the B/S-but you check it-right?

Guess you don't have a signal generator-that's the quickest way-go to
the
audio section and work backwords from audio to RF.

Mike
Le Claire Iowa

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