DuMont Blonde Revere Restoration
 

Hi all,

I was able to make good progress over the rainy weekend on my blonde DuMont Revere RA-113. This is the set that I picked up at the beginning of August and wrote about in this thread: http://www.videokarma.org/showthread.php?t=258995

I had the advantage of Phil Nelson's excellent write-up on the restoration of his RA-113 which was a great guide (thanks Phil)! Here's the chassis on the workbench before I started:
http://i1216.photobucket.com/albums/...ps62bc834c.jpg
http://i1216.photobucket.com/albums/...ps4ffc91a5.jpg

I decided to replace the electrolytics under the chassis instead of restuffing, since there was plenty of room. The modern replacements are so much smaller!
http://i1216.photobucket.com/albums/...ps03e73005.jpg

The flyback looks great. The new HV caps are from Just Radios in Canada:
http://i1216.photobucket.com/albums/...ps55babda5.jpg
http://i1216.photobucket.com/albums/...ps31d503cf.jpg

After restringing the dial cord (which fortunately was easier than I thought it would be) I decided to try a power up with a metered variac. No smoke or strange noises, and current draw was just under two amps.
http://i1216.photobucket.com/albums/...ps48a386c9.jpg

I got nice clear audio and a very dim raster:
http://i1216.photobucket.com/albums/...pseb85a3ae.jpg

I recalled that both HV rectifiers tested very weak, so replaced them both. Then things progressed quickly.
http://i1216.photobucket.com/albums/...psb1d3309e.jpg

Here's after adjusting the ion trap:
http://i1216.photobucket.com/albums/...ps60a05ef9.jpg

And after adjusting the horizontal frequency and the other usual stuff:
http://i1216.photobucket.com/albums/...ps7a3bc89d.jpg
http://i1216.photobucket.com/albums/...psaf23c577.jpg

I'm very pleased with the nice, bright picture! The video response is great enough that I see the color interference dots. There are still 4-5 paper caps yet to replace. The picture is somewhat canted, so I need to adjust the yoke and/or focus coil. And as some of you know, I have what I hope is a new old stock (or rebuilt) 17BP4 that I bought on eBay due to arrive on Thursday. There seems to be plenty of life left in the original 17AP4, but it will be nice to have a spare. The tuning eye tube is very dim, so I'll need to find a replacement.

This was a lot of fun and it's almost a let down at how easy it was :yes:

I'm looking forward to watching bandersen restore the one he's got!

-Clark

Nice looking set hope you get plenty of tvtime on this set a great find just as well happy veiwing...Timothy

Wow, looking good. All that in one weekend? You work faster than I do (well, I did have a couple of issues like a busted tuner gear). An original 17AP4 suggests this was a low-hours set. Maybe it led a pampered life and retired early.

That blonde cabinet should be really striking. The RA-113 is very enjoyable to watch -- big screen, great audio.

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

That's a good picture!

Hi Phil,

Actually, I had also done some work on it last weekend, too. And before that, I studied the SAMS and Riders so I knew what I was getting into. (Thanks again for scanning the SAMS folder!)

I do think it's probably a low hours set. The 1/4 amp pigtail fuse was blown and jumpered with a 2 amp fuse :sigh: At least one of the filter caps was a dead short so it may have been pushed aside quite a while ago. I'm very glad that the seller hadn't tried to power it up.

The audio on TV is still lower than it should be, although the peak for good audio corresponds well with the best picture. The volume receiving FM stations is much louder. I haven't attempted any alignment yet.

It turns out that the original focus control is OK, but I'm still glad to have a back up. Now I'm just waiting to see if this CRT I bought on eBay for $50 make it in once piece:
http://i1216.photobucket.com/albums/...ps7ed010fe.jpg

Hey, that's was quick ;) Nice job! I hope mine goes as smoothly and good luck with that VDC CRT :yes:


P.S. brianweber4 could you please edit your post so it doesn't duplicate every single photo ?

Yes, the TV volume was low until I did some tweaking, as noted in my article. The FM radio volume is still significantly louder, and I suspect that is just the nature of the beast.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Impressive.

My RA-113 has 3 15K capacitors, where I see 2 on yours.

Your entire set looks lovely.

Yah, mine has three 15KV caps: two above the platform and one below.

Phil Nelson

http://antiqueradio.org/art/DuMontRA...CageBefore.jpg

http://antiqueradio.org/art/DuMontRA-113HVCageAfter.jpg

Nice work, Clark. That sure looks like a super clean chassis. I suppose it helps that these are mounted vertical in the cabinet. Great looking picture you have too. :thmbsp:

Thanks for all the nice comments! I'm really enjoying the high quality of this set. It's the one and only DuMont that I have experienced and it has not disappointed. And mine also has three .00047 uF HV caps, I just snapped the photo before I had installed the one on top of the two 1X2s.

My next steps will be to replace the few remaining paper caps (they're in the little shielded compartment in the sync section) and find a replacement 6AL7. I have also yet to do any work on the cabinet, which fortunately won't need much.

The VDC CRT is scheduled to arrive Thursday by USPS. It's being shipped in its original box which has some water damage. I'm hoping that they double boxed it.

-Clark

So glad to see another DuMont being brought back to life!

VERY impressive !

That's true. The deviation of broadcast FM radio is much higher than that used for TV sound. 75KHz vs 25KHz IIRC. This deviation difference results in the FM radio stations being louder than TV station sound.

beautiful set, Clark. I love that model and the blonde finish.

Sorry to arrive late at the party but let me say as well that that is a very nice set. Glad that things are going well with it and I look forward to following more progress.

Thanks for taking the time to share with us.

Well, the VDC CRT arrived a day ahead of schedule. The good news is that it made it in one piece and it tests like new!
http://i1216.photobucket.com/albums/...psa325b482.jpg
http://i1216.photobucket.com/albums/...ps560a5869.jpg
http://i1216.photobucket.com/albums/...ps3bd3dbb7.jpg
http://i1216.photobucket.com/albums/...psb92a729f.jpg
The not so good news is that I don't think it's a 17BP4. It's got an extra pin on the base (number 6) and the neck looks to be about an inch shorter than the 17AP4. I'm guessing that this may be an electrostatic focus version of the CRT, something like a 17BKP4. But from what I can see in my tube manual, all the electrostatic focus versions are 90 degree tubes, not 70 degree tubes. But the overall length of the 90 degree tubes is much shorter than this one. I may just have to try it and see what happens.

Meanwhile, I tweaked the horizontal waveform which cured some instability. Now it's textbook :thmbsp:
http://i1216.photobucket.com/albums/...ps0fb29862.jpg

That extra pin might not be connected to anything electrically. Some CRTS have that to help the CRT socket hold on. Got my fingers crossed :)

Hi Bob,

Thanks. Eric H thought the same thing. The shorter neck isn't a problem since it won't need the ion trap. I'll give it a try!

I received my NOS 6AL7 "indicator tube" so the DuMont now has it's green eye glowing properly. I still need to check/replace the resistor in its connector.
http://i1216.photobucket.com/albums/...psba3c5426.jpg

Here, Ginger explains to the Skipper how good they look on a 1950's DuMont :D
http://i1216.photobucket.com/albums/...psc00f4ca2.jpg

I'm not sure I'll have much time to play old TV this weekend, but I'm very curious to find out if the VDC CRT is going to work!

-Clark

I imagine that in 1964-66, there were still a few 1950 DuMonts in use. It looks great!

Somewhere I have an issue of PF Reporter from the mid-1960s that has an article about working on the RA-109 sets. It was written by a TV repairman who had a customer that still used one regularly and would have him service it.

I did a bit more work on the DuMont. I replaced the few remaining paper caps, including the ones hiding in the small shielded compartment. I also replaced a few more resistors, including the 3.3K in the socket for the 6AL7 indicator tube, which ahd drifted to more the 5K:
http://i1216.photobucket.com/albums/...ps7b7df925.jpg

I had planned to try the VDC CRT in the set, but I was unable to remove the yoke. It's such a tight fit, that it wouldn't slide over the repaired base of the 17AP4. I was afraid that something like this might happen when I was repairing the base and I thought I had done a good job of keeping things compact. Even after removing the electrical tape, no dice. I was afraid that if I tried too hard that I might damage the yoke, the base or worse. So I abandoned the idea for now. Since the old CRT is making a very nice picture, I can afford to wait. I think what I will need to do is to carefully grind down parts of the base with a Dremel tool. At least I know that the repair I made with the black, sensor safe RTV is nice and sturdy:
http://i1216.photobucket.com/albums/...ps495687e0.jpg

With everything back together, the picture is rock solid and the audio is excellent-- lots of bass with the big speaker.
http://i1216.photobucket.com/albums/...psa6641073.jpg

Wow, that picture is outstanding. There is nothing like a DuMont! I can understand your wanting to try out the other CRT, but this one may look good for a very long time. I hope you can put this TV in a place where it gets watched regularly. Between the "big screen" and tasty audio, this model makes a great daily driver.

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Thanks! I'm really in love with this set. In my mind, the early DuMonts certainly live up to their reputation.

Another drawback to no being able to remove the CRT is that I can't clean the back of the safety glass or the front of the CRT. It's not too bad, but there is some noticeable crud in there. That may eventually motivate me to remove the CRT, more so than trying out the VDC CRT.

I do want to find just the right spot for this set, so that it can be thoroughly enjoyed. I'm finding that having doors makes that a bit more challenging. This will be the fifth set in the living room or dining room. I think I'm approaching critical mass!

-Clark

This is a great looking restoration wish I was the lucky person watching old shows on that set great job well done....Timothy

Nice job. There is nothing like that clear soft b/w picture of a vintage TV when it's restored correctly. There's something so much better about it than even a new flat screen!

Thanks for the nice comments, Timothy and Joe! I'm looking forward to watching many classic B&W movies on it this winter.

That picture looks amazing Any chance on doing a YouTube

since the crt tests good and really looks good I wouldn't worry about replacing it , cleaning it I would lay the set on its face , remove the crt with yoke and bracket stull attatched , clean and put it back in , I was going to do this to my ra-109 but since I can't lay it on its face and the glass metal tube is a bit more fragile I gave up.

mike