[Ron Ramirez]

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/HQ...9X_008.jpg]

[Ron Ramirez]

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.

[rfeenstra]

That looks like a nice radio to restore.  Are all Hammarlunds that un-cluttered?

[Ron Ramirez]

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.

[Ron Ramirez]

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.

[John Bartley]

Sounds like you are having fun Ron. Good on ya!

cheers

[Ron Ramirez]

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...

[Ron Ramirez]

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.

[mikethedruid]

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-fo...SwEetV7e3l

[Ron Ramirez]

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.

[Paul Philco322]

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

[mikethedruid]

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.

[Eliot Ness]

Ron, those were some pretty ugly (and possibly cold) solder joints before, nice job cleaning them up!

[EdHolland]

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) ?

[Ron Ramirez]

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...