wrote in message
...
On Feb 2, 11:43�pm, wrote:
� � �hi guys,
� � �i am restoring an hq180a. �been a while since
i messed with tubes,
(abt 20 yrs) am in need of a little direction. �i
checked �& replaced
bad tubes, verified b+ v. �2 problems, may be related???
on top band,
very poor reception, & when u adj ant. control, u hit a
spot that
causes oscellation or motorboating. �prob #2...on top 2
bands, cw sigs
have a raspy note. �not t9 at all. �it is a high s/n
rcvr 6377. �kind
of neat, has spinner knobs, noise blanker, & 455 kc if
brought out to
rear apron. �i guess previous owner did mod, but it sure
looks
factory....solder connections, etc.
� � �would appreciate any and all guesses.
� � �tnx, pete, k2iqk

hi again, tnx for the replies..i did clean all wafer sws &
pots,
didn't clean main tuning cap..have bama prints for rx..will
try
voltage & resistance checks..full alignment sounds like a
good idea..i
have sig gen..1st & 2nd ifs would be difficult because sig
gen calib
not great..i dont think if alignment is my main prob..but
will do all
hf aligns..i'm glad to get back into tubes..its like
restoring a
classic car, but alot cheaper...hi hi. tnx agn..if u have
any more
ideas, pse email me.
73, pete

I should have added to watch out for the power supply
filter caps also. Bad caps could account for the hum and
rough CW notes plus allow some feedback through the power
supply although at RF the by-pass and decoupling caps should
prevent that. Try the power supply filter caps first.


--
---
Richard Knoppow
Los Angeles, CA, USA

Don't mess with the alignment yet! If you don't have a well
calibrated signal generator (a frequency counter to go with it would
be better) you will probably just screw up the IF alignment. It is
important to get the third if aligned to exactly 60 kHz for the
sideband selector function to work properly. You will need a sweep
generator to properly align the first (3035 kHz) IF. The IF alignment
is unlikely to be the problem with the oscillation. Only attempt the
IF alignment if you have the proper equipment and know how to use it.
If the alignment hasn't been messed with, it is probably OK.

Make sure all tube shields are in place and all the bypass capacitors
are good. The HQ-180 uses mostly ceramic caps, but as mentioned, they
can be bad. Replace the filter caps first, then go from there. --Ed