[Hammarlund] Fw: Question about warm-up vs. signal strength-REPLY

[Mike & Coreen Smith]

Hi Guys,

As I was just typing a reply to another Hammurland list member, your various 
reply emails came through.
I am overwhelmed so I am just replying to the group now instead of 
individually.  I am not a fast typist by a long shot.

I have checked each tube on a Tube Tester and they all checked very well, 
with the exception of
2 (the 6c4 and I think a 6be6), both which I swapped out with new or used 
tubes rating 75% or higher on my borrowed tester.
I returned the tester, but have purchased 2 more online, but they are not 
here yet.

Maybe I should go through and swap out 1 tube at a time, give them each a 
10-20 minute warm-up and
see if I can find a tube that is perhaps "Weak" after warmup.

It's not a really "serious" issue, but I feel I am losing 6-12dB after 
warmup....hmm, maybe it is bordering on serious, hi

It works waaaay better now with a new "6c4" and a new "6be6", but it's still 
not "quite" up to snuff, even though all tubes are reading 75% or better.

This must have been a real rockin' rig back in the 60's !

Mike ve9aa

p.s.-Carl suggested my SS transceiver as a signal source.   I actually 
hadn't thought of that. Hmmm !
I presume 3 or 4 watts into a dummy load ought to work.

Mike, Coreen & Corey Smith
699 Rte 616 Keswick Ridge
NB
Canada
E6L 1T1
    =============================
    ----- Original Message ----- 


    Hi Gang,

    I've got my new-to-me HQ-170a running pretty fair now .  Really a very 
nice RX.  Thanks of course are due in part to the help I have rec'd from the 
FB folks on this list.

    Cleaned lots of contacts, replaced a couple tubes,. etc.  Works very 
well.  (some of the tubes in it are marked "Hammarlund", so presumed 
original) The inside underneath looks nearly new and there is almost no rust 
or other damage on the face/case whatsoever) Still a few tiny bugs to work 
out,

    One thing I have noticed is that when I first turn it on, the signal 
from the Xtal calibrator is (for example) s9 on 20m, but after the radio is 
warmed up (15-30 minutes later we'll say) the signal has dropped to perhaps 
S6 or S7)

    I notice it fairly consistently right across the spectrum.. Ie: on 6m, 
it's S3 when first turned on, holding steady back to s1 after warm up. (it 
will be rock steady @ S1 for days, so I don't think it's the onboard Xtal 
cal, but the RX itself.)

    Is this pretty much indicative of a RX ~45 years old, or are there 
components that I should be looking at swapping out?
    (ie: caps, IF tubes, etc.)  I'm quite happy with its performance the way 
it is now, but I suppose if I could make it better. . . .

    I have not yet done an alignment on it.  I am working a little on my old 
PACO signal gen to see if it will be accurate enough to use for an 
alignment, otherwise I may not actually do one until I have a better signal 
source.

    BTW, last weekend we had an opening on 6m and I had some W9's in here 
well over the s9 mark, so I was quite pleased about that. I am sure my 2x8el 
yagi antennas on the end of the coax cable didn't hurt however ;-)

    Cheers,

    Mike VE9AA

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