HQ-180A - Somewhat Deaf on Upper Bands

[KW4H]

With some of the other issues either behind me or in the process of repair, I have a question about the 15 - 30 MHz band.  When the band selector is rotated into this position, the receiver becomes very, very quiet.  Like it's put on earmuffs.  You can hear signals but you have to crank the RF gain all the way to maximum and give the AF gain some more juice.  Before I jump to conclusions and assume that an alignment touch-up is going to have to go onto the list -- just what is expected with the HQ-180A when it comes to the upper bands?  I owned one of these radios when I was a teenager (1974 - 1976) and it's been so long I have no recollection of expected upper band performance.  Tubes have been tested and swapped out where I thought it could help.

73 - Steve, KW4H

[WA2SQQ]

I suggest you check out K7PP videos on YouTube he goes through the entire alignment. His verbal commentary also offers some very good information on restoring these receivers
https://youtu.be/sGwBds7R1TY

[KW4H]

I suggest you check out K7PP videos on YouTube he goes through the entire alignment. His verbal commentary also offers some very good information on restoring these receivers
https://youtu.be/sGwBds7R1TY

Thanks, will do.

[WD5JKO]

    Steve,

   It helps to have a good signal generator with good accuracy, and a variable attenuator to vary the output amplitude.

My HQ-110 had a similar issue, and the problem was mostly alignment related. On the 110, there are a bunch of metal cans with slug tuned coils within.

I know, you know that...But I was surprised that some had two slugs inside, one for one band, and the other for another band. These were not the IF Cans. Some had blocked access on the bottom,

so the bottom slug had to be adjusted with the alignment tweaker going through the top slug such that the turning of the bottom slug did not also turn the top slug.

This requires a special alignment tool with the bottom Allen portion be larger than the round shaft leading to the Allen end. This way, you can turn the bottom slug with a minimum

of disruption in the top slug, but not zero! Most likely on my 110 a previous owner used a diddle stick in a way that caused a severe miss-alignment.

In the process of setting mine up, I screwed the pooch on at least 1 band, and did so 3 times! I needed to pay close attention.

I hope you don't have any stripped out, or cracked slugs. I had one that was driven down too far, and it was unthreaded, and cocked.Yes I did it!! I was able to remove parts underneath the

Can, and get my diddle stick inserted from the bottom, and regain the slug in the threaded coil form...I was lucky.

Jim
Wd5JKO

[KW4H]

    Steve,

   It helps to have a good signal generator with good accuracy, and a variable attenuator to vary the output amplitude.

My HQ-110 had a similar issue, and the problem was mostly alignment related. On the 110, there are a bunch of metal cans with slug tuned coils within.

I know, you know that...But I was surprised that some had two slugs inside, one for one band, and the other for another band. Some had blocked access on the bottom,

so the bottom slug had to be adjusted with the alignment tweaker going through the top slug such that the turning of the bottom slug did not also turn the top slug.

This requires a special alignment tool with the bottom Allen portion be larger than the round shaft leading to the Allen end. This way, you can turn the bottom slug with a minimum

of disruption in the top slug, but not zero! Most likely on my 110 a previous owner used a diddle stick in a way that caused a severe miss-alignment.

In the process of setting mine up, I screwed the pooch on at least 1 band, and did so 3 times! I needed to pay close attention.

Jim
Wd5JKO

Jim -- yup, the Hammarlunds have some of those cans where there are tunable slugs at the top and the bottom.  The HQ-180A has several of them.  I have the special alignment tool, but am very conservative in fooling with the alignment and tend to "circle the problem" for a bit before diving in.  The reason is that these are 50+ year-old radios and some of those slugs can be hard to turn and are known to snap.  Got plenty of signal generators here, including a SG-85B (a surplus one built like a tank).  Interesting about signal generators, though -- one of my favorites is a TinySA.  Although, the SG-85 has other features the TinySA doesn't. 

Steve, KW4H