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View Full Version : Started fixing the Cheyenne



W1GUH
01-26-2012, 08:34 PM
And the results are very encouraging. All the tubes light up and get hot, and no magic smoke was seen or smelled. In fact, at first the scent that emanated from it was that of "New Heathkit". Very healthy sign, at least for the radio!

I can hear the VFO working good in a receiver with a probe by the driver tube; probably indicates that up to the driver all's cool. But I can't peak the signal with the driver tune control, nor does it work about 80. Visual inspection shows lots and lots of crud on the bandswitch, so de-oxit is called for. BUT, despite putting both bottes that I have in a "safe" place last time I straitened up, do you think I can find either? Nope!!!! "Putting it in a safe place" can so often translate to "Safe from me ever seeing it aging!" Argh!!! Well, gotta go on a searchin' safari (with apologies to the Beach Boys.)

There are only a small handful of mic caps to change and no paper caps (Damn! Heathkit really put good stuff in their radios) so that'll be easy. And the few that there are are in the final tank circuit so would have no effect on driver tuning. My money's on de-oxit getting that baby working. THEN I can get on the window with REAL AM!

The PS remains solid. The final pulls 175 ma and the PS doesn't complain at all. (Sure glad that's a 6146!) So...soon's I get this lack of drive fixed it's goin' on the road.

Looking ahead...

The G-76 is not far behind. I've picked up the DC supply for the Eico 753 and that is a prime candidate to power the G-76. Voltages are very compatible, and there's lots of room in that for the necessary modifications. The main one is a relay to switch the B+. Already have the relay & it should be a very simple job to put that in.

Pix later. Oh, yea...what's the best way to get crud off the chassis? There's lots of it and it'd be nice to get it purtied up to match the pretty exterior, which is in very good shape.

w2amr
01-30-2012, 06:17 AM
And the results are very encouraging. All the tubes light up and get hot, and no magic smoke was seen or smelled. In fact, at first the scent that emanated from it was that of "New Heathkit". Very healthy sign, at least for the radio!

I can hear the VFO working good in a receiver with a probe by the driver tube; probably indicates that up to the driver all's cool. But I can't peak the signal with the driver tune control, nor does it work about 80. Visual inspection shows lots and lots of crud on the bandswitch, so de-oxit is called for. BUT, despite putting both bottes that I have in a "safe" place last time I straitened up, do you think I can find either? Nope!!!! "Putting it in a safe place" can so often translate to "Safe from me ever seeing it aging!" Argh!!! Well, gotta go on a searchin' safari (with apologies to the Beach Boys.)

There are only a small handful of mic caps to change and no paper caps (Damn! Heathkit really put good stuff in their radios) so that'll be easy. And the few that there are are in the final tank circuit so would have no effect on driver tuning. My money's on de-oxit getting that baby working. THEN I can get on the window with REAL AM!

The PS remains solid. The final pulls 175 ma and the PS doesn't complain at all. (Sure glad that's a 6146!) So...soon's I get this lack of drive fixed it's goin' on the road.

Looking ahead...

The G-76 is not far behind. I've picked up the DC supply for the Eico 753 and that is a prime candidate to power the G-76. Voltages are very compatible, and there's lots of room in that for the necessary modifications. The main one is a relay to switch the B+. Already have the relay & it should be a very simple job to put that in.

Pix later. Oh, yea...what's the best way to get crud off the chassis? There's lots of it and it'd be nice to get it purtied up to match the pretty exterior, which is in very good shape. 409 or spray 9 should remove the chassis crud. Be careful , don't get it on any painted surfaces.

K7SGJ
01-30-2012, 07:17 AM
A guy I used to work with restored Collins stuff. He removed anything delicate, covered the chassis with Murphy's, let it sit awhile, swished it around with a paint brush, hosed it off, and let it dry in the sun. Then he would go ahead restore the radio; and when finished they looked showroom great. I never saw any signs of rust or any other negative effects. I think if it were me I'd hit it a lick with the air hose after the water rinse.

W1GUH
01-30-2012, 08:06 AM
A guy I used to work with restored Collins stuff. He removed anything delicate, covered the chassis with Murphy's, let it sit awhile, swished it around with a paint brush, hosed it off, and let it dry in the sun. Then he would go ahead restore the radio; and when finished they looked showroom great. I never saw any signs of rust or any other negative effects. I think if it were me I'd hit it a lick with the air hose after the water rinse.

Murphy's what?

W1GUH
01-30-2012, 08:06 AM
409 or spray 9 should remove the chassis crud. Be careful , don't get it on any painted surfaces.

I'll give it a try.

K7SGJ
01-30-2012, 08:46 AM
Murphy's what?

Murphys oil soap. http://www.colgate.com/MurphyOilSoap/products/original-formula

W1GUH
01-30-2012, 11:01 AM
Are these two suggestions for crud, pitting, or both? The chassis is heavily pitted.

K7SGJ
01-30-2012, 02:32 PM
I don't think there is much to help the pitting. The Murphys cleans up the chassis very nicely. Perhaps the pits won't be as noticeable once the crud is cleaned out. If not, well, ......you know.............that's the pits.

W1GUH
01-30-2012, 03:19 PM
Thanks. 409...Murphy's....elbow grease --

N8YX
02-07-2012, 05:13 PM
Thanks. 409...Murphy's....elbow grease --

How goes the project?

W3WN
02-10-2012, 08:55 AM
Murphy's what?
I'd guess Murphy's Oil Soap. (No relation to Murphy's Law.)

K7SGJ
02-10-2012, 10:43 AM
I'd guess Murphy's Oil Soap. (No relation to Murphy's Law.)

Yep. Just lather that bad boy up, scrub, rinse, dry, and spit (shine, that is). Guaranteed to clean your chasis, so to speak.

W1GUH
02-10-2012, 12:52 PM
Thanks for the nudge...that project has languished on account of a higher-priority transcription project. That's done now...I'll have that bad boy transmitting soon!

So...409 or Murphy's to clean it -- usually use 409 here -- & as for pitting...learn to love it?

W1GUH
02-19-2012, 08:25 PM
Finally got through the higher-priority tasks and took a good look at the Cheyenne today, What I found was a mod that doesn't seem to make a lot of sense, Somebody thought that an 0A2 wasn't good enough for VR, so the added 3 105v zener diodes; One each for the screens of the VFO tube, the buffer & the driver. Ripped those out and now what I'm left with is a LV line that's connected somewhere where it shouldn't be. Ran out of steam looking for that, will probably pick up on this again tomorrow.

Wonder what the guy was thinking? So far I haven't found anything on the 'net about it. And the Cheyenne never really had a VFO stability problem, so I gotta wonder what that guy was thinking.

Ah, well, fixing it is a lot of fun. It's been said that restoring a vintage Heathkit is almost as much fun as building it in the first place. Sure is!!!!