On Apr 22, 1:00*pm, "Joe L." wrote:
Hello. I've been restoring a Hammarlund HQ-145 that has been neglected
for many years. After performing the RF alignment, I noticed that the
sensitivity at 10 Mc on the 10-30 Mc range is about 10 dB worse than
when tuned to 10 Mc on the 4-10 Mc range. This was even after adjusting
the 10-30 Mc ANT and RF coils as instructed by the manual.

The sensitivity is actually much better at 30 Mc than it is at 10 Mc on
that band setting. I wonder if this was a design compromise? Or is there
still something flaky with my HQ-145?

I would appreciate it if someone else with a working HQ-145 would please
check whether theirs operates the same way. Just tune into WWV at 10 Mc
on both band settings and see if there's much difference in signal
strength. Thanks!

Tnx,
Joe K9LY

I had one of these a while back. The first thing I noticed about the
HQ-145 is the lack of real electronic components within a huge
cabinet. There is plenty of real estate there! Some of the circuits
are pretty much bare bones and this includes the conversion/
oscillators. When the second conversion oscillator "Kicks In" it makes
up for the overall gain that was lacking on the lower band which was
single conversion. The HQ-180/160 didn't P-600 so I suspect they were
the top design and all the others just had stuff taken out to cut the
overall cost of the receiver. This radio was one step up from the
single conversion HQ-100 which suffered from image rejection problems
fixed by the double conversion of the HQ-145. I think the double
conversion setup was minimal and could have been more well thought out
to balance the gain a bit better.


Tony