Hammarlund HQ-129-X -
Ron Ramirez - 08-28-2019
Okay, boys and girls, here we go with another exciting chapter of
Ron's Radio Rectifications (the actual byline used by
Antique Radio Classified years ago with articles I wrote for them).
This time in Handyman Corner, we have a Hammarlund HQ-129-X.
The backstory...
Earlier this summer, I had decided that this should be the year that I finally get a longwire antenna put up. It helped matters greatly that my son-in-law volunteered to do the work for me. About that time, I started thinking about what might be a really good shortwave receiver to use with the new longwire.
For some reason, Hammarlund came to mind. I really don't know why. Maybe because, in 45 years in the radio hobby, I had never owned a Hammarlund prior to this year.
I had an HQ-180 as my goal, but when the opportunity presented itself to purchase an HQ-129-X at Radiofest 2019 (Addison, Illinois) for what I thought was a very reasonable price, I did not hesitate. I brought the HQ-129-X home with me from Radiofest, although it took a side trip to Galena, Illinois and ultimately Clear Lake, Iowa before we headed home.
So...the radio as it looked when I bought it at Radiofest:
I did not care much for the non-original Dakaware knobs, and soon replaced them with knobs that looked more like the originals - not exactly the same, but closer:
These chicken head knobs have slightly rounded ends, sort of like the original knobs. The tuning and band spread knobs are like those used on the HQ-180 and similar Hammarlund sets, but still better looking than the Dakaware knobs.
Click on the image below to see a full sized image of the schematic for this radio (WARNING: 6.2 MB download).
[Image: https://philcoradio.com/images/phorum/HQ129X/HQ129X_008.jpg]
RE: Hammarlund HQ-129-X -
Ron Ramirez - 08-28-2019
Yesterday, I pulled the chassis out of the cabinet.
Turning it upside down, I wasn't sure what I would find...
As you can see, most - not all, but most - of the original paper capacitors have been replaced with new yellow film caps. The quality of the cap replacements is not quite to my liking, but I may leave most if not all of them alone.
There are some issues I will need to address, though:
I don't care for how the original twist-lock electrolytic was replaced by individual electrolytics with some masking tape wrapped around them. These will be replaced with another twist-lock unit. I considered buying a new twist-lock from AES, but have since decided to open up a twist-lock from the junkpile and restuff it with new Nichicon electrolytics.
Left side of chassis, looking at the bottom: No less than seven original paper capacitors which were not replaced. I will replace them. Since the vast majority of capacitors were replaced with yellow film and the originals discarded, I will not restuff these either.
Back of chassis under speaker terminals: Two more original paper capacitors. One of those, .05 uF, is connected between one side of the line and ground!
It will be replaced with a new .01 uF X-Y safety cap. The other will be replaced with a new .047 uF yellow film capacitor.
Additionally, I noticed that R54, which is supposed to be 4K at 5 watts, was replaced with a 10K, 10W unit. That will reduce the B+ to the screen grids of the front end tubes as well as the first and second IF amplifiers. It will be replaced with a new 4K, 10 watt resistor which I just happen to have on hand.
Also, it appears to have its original rubber power cord which is cracking. It will receive a brand new black power cord.
All of the tubes are good save two: the 6K8GT which is marginal, and the 0C3 voltage regulator tube which my tester won't test. Its base is very loose so I'll just replace it anyway.
RE: Hammarlund HQ-129-X -
rfeenstra - 08-28-2019
That looks like a nice radio to restore. Are all Hammarlunds that un-cluttered?
RE: Hammarlund HQ-129-X -
Ron Ramirez - 08-28-2019
I don't know, this is the first Hammarlund to ever cross my workbench. But I suspect they are all made in a similar manner.
RE: Hammarlund HQ-129-X -
Ron Ramirez - 09-01-2019
While I haven't posted anything on this subject in a few days, I am still working on the HQ-129-X.
All of the original paper capacitors which had not been replaced now have been.
As for the yellow film caps, I know that I said (in post #2 above) that I may leave most if not all of them alone. But, being the perfectionist that I am, I could not just leave that sloppy work alone. So I'm redoing them. I have to anyway, as I am also replacing all of the resistors. I am reusing as many of the yellow film caps as I can.
I also replaced the volume control. It had been replaced before with an obvious junkbox part. It now has a brand new 250K audio taper control with switch, from Radio Daze. Now that switch snaps on and off as it should.
Photos tomorrow. There is a lot more work remaining to be done on this set, too.
RE: Hammarlund HQ-129-X -
John Bartley - 09-02-2019
Sounds like you are having fun Ron. Good on ya!
cheers
RE: Hammarlund HQ-129-X -
Ron Ramirez - 09-02-2019
Thanks John.
Progress:
I've removed and reattached most of the yellow film caps now, and have tried to do a neater job. I have also replaced most of the resistors.
New caps replacing old:
more...
RE: Hammarlund HQ-129-X -
Ron Ramirez - 09-02-2019
At the 6H6 (2nd detector) tube socket.
Before:
After (by the way, the ceramic discs are 100 pF, NP0):
New volume control with power switch, 250K, audio taper:
Now I'm waiting on a couple tubes from Bob Dobush (findatube.com) and some resistors from Mouser, so that I can hopefully wrap this up.
Work will continue after I get over the next chemo session...in about a week and a half.
RE: Hammarlund HQ-129-X -
mikethedruid - 09-02-2019
Too bad you didn't look on eBay. You can buy complete NIB tube sets for Hammarlunds on there. I have bought sets for both of mine. Here is a link to the one for yours.
https://www.ebay.com/itm/NIB-tube-set-for-Hammarlund-HQ-129X-receiver/362598053237?hash=item546c873575:g:EDcAAOSwEetV7e3l
RE: Hammarlund HQ-129-X -
Ron Ramirez - 09-02-2019
I did see those on the auction site recently.
Why do I want to spend $73 when only one tube was (possibly) bad and one marginal? So I only ordered the two I needed from Bob since the rest are still good.
RE: Hammarlund HQ-129-X -
Paul Philco322 - 09-02-2019
Dobush is a good source and easy to work with, his wife answers often and is a peach.
That underside looks real clean. You will have a fine receiver, bet you can get WBZ from Boston, AM 1030 with that one.
Paul
RE: Hammarlund HQ-129-X -
mikethedruid - 09-03-2019
I understand, Ron. I just like to have a full extra set for all of my radios. You should see the shelves full of tubes I have collected over the years, all tested and boxed. LOL ! hope when I'm gone nobody is stupid and throws them out. They could bring some money on eBay.
RE: Hammarlund HQ-129-X -
Eliot Ness - 09-03-2019
Ron, those were some pretty ugly (and possibly cold) solder joints before, nice job cleaning them up!
RE: Hammarlund HQ-129-X -
EdHolland - 09-04-2019
Looking good Ron, I am enjoying following along with your progress.
Didn't I see that you also bought a second communications receive (or am I perhaps mistaken) ?
RE: Hammarlund HQ-129-X -
Ron Ramirez - 09-14-2019
Back to work on the HQ-129-X.
Remember the mess that was the set's electrolytic capacitors? If not, here's a reminder.
Thursday evening, I returned to the workbench and decided to prepare an old twist-lock capacitor I had found in the junkbox.
I cut off the aluminum at the bottom end and carefully disassembled the unit.
Then I installed three new Nichicon 10 uF, 500V electrolytics I had bought just for this purpose.
Soon, I had it all together again:
All restuffed, reassembled and ready to go where the original electrolytic once was mounted. The original was a four section unit, also containing a 20 uF, 25V electrolytic. Since the twist-lock electrolytic can I found only has three terminals, I will install a new 20 uF electrolytic direct between the output tube cathode and ground.
more...