Hammarlund HXL-One Amplifier modifications requested

[KI4VEO]

I recently acquired an HXL-One that is in need of restoration.  This will complete my trifecta (HQ-160 & HX-50) AM station for me.

I have seen very little in regards to mods for this amp, but a few posting on eHam elude to some.  In particular, the input tuning and parasitic suppression (darn 572B tubes).

If any of you have a link, or some information (even something scribbled on a napkin), please share it with me so I can complete this before I become an SK and my widow sells everything to Radio Mart for $100 (don't get me started!!)

[WBear2GCR]

Never heard of it, never laid eyes on one!
In fact didn't know they made an amp!

But, I'd take a look at the amp and compare it to those other 572b/811a amps and mods that are out there already. It's got to be rather similar.

The Collins, Heath and Gonset come immediately to mind.

As far as parasitics there are two main schools of thought one is the Rich Measures and the other was mentioned on here earlier this year, and may be linked either here or on Amwindow's tech pages - that one is based on making an LC supressor instead of an LR supressor. I've also seen where a large chunk of ferrite is placed adjacent to the tube, fwiw, and it is said that this works too. All of this is on the web somewhere! 

You may already be aware of this stuff...

If you happen to find a schematic and post it up here, perhaps a few will come up with some thoughts?

Hey! A jpg of the beast, inside and out might be kewl to see!

               _-_-WBear2GCR

[KI4VEO]

I already have been e-mailing Richard regarding my Yaesu FL-2100B - it also uses a pair of 572B tubes.

Hers a link to the Hammarlund HXL-One: http://www.rigpix.com/linears/hammarlund_hxlone.htm

The above link is a bit prettier than what I have coming.  As I go through mine, I'll be sure to snap some pictures.  I have attacvhed a couple of jpg's of the amp as it is now.  After all the electrical work is done, I guess I'll have to strip and repaint the front panel.  Then relabel using the Datak rub on transfer lettering - and finish it off with some clearcoat.

Ya just really gotta love boatanchors to buy one, but most that have them, really like how the amp operates.  After a few modification, of course.  I figured someone on here would own one.

Come to think of it - someone does..........ME!

I'll post a schematic on this as soon as I get the manual.  Maybe some of the members here can give me some suggestions on some mods.

[WBear2GCR]

The link you posted happens to have the a link to download the manual, in case you did not notice that. I'd have done that, but on dial-up 4 meg is about 40 mins or so... 

For better options on the presstype, go to a store that sells printing supplies, they tend to have a variety of presstypes in various sizes and fonts.

Looks like urs has non-stock knobbers.

The specs look a bit "optimistic" for the AM power at 500watts. Probably closer to 150watts of carrier is possible, 500watts PEP? But that's just a partially educated guesstimate.

Looks real similar to the SB-200 (that's the right one, I think) by Heath, just squished in more... not sure why the tubes are pushed together so close when there seems to be extra chassis space, but whatever...

Unless there are some known problems with the unit, I'd just clean it up and use it as is. But that's just my take on it.

              _-_-bear

[KI4VEO]

I already did a download of the manual zip file.  I concur with your opinion of the overly optimistic spec on the power output.

My concern is the HV filter caps.  Being so old, they may not do well.  I guess I'll just have to bring everything up very slowly on my variac and see what happens.

[KB2WIG]

   " My concern is the HV filter caps. "

Its a gud idea to  bring thigs up slow....

the  engenrs, well, I'm sure they were opperating under constraints to keep things small... them filt caps are squashed right next to the xfermer. prolly dryed out.....  klc