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  #1  
Old 08-10-2014, 05:06 PM
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Capehart 325 restoration

Way back in May, 2010 I came across this "raped curbside" Capehart on ebay.

http://www.videokarma.org/showthread...44#post2972644

That sparked another thread where pugs5061 was thinking about getting it: http://mail.videokarma.org/showthread.php?t=247970

Well flash forward to 2014 and the chassis is sitting on my back porch awaiting restoration



Now here's the rest of the story. I had been contact a few months back someone was referred to me by Phil Nelson who was in my area and looking to have a vintage Admiral TV restored. Well we got to talking and he said he also had some other sets he'd like restored someday too. He sent some photos and there it was - that same Capehart.

It turns out he originally found it out on the curb (or maybe it was his wife ?) after the copper thieves neck it and made off with the yoke. He listed it on ebay several times and had some winning bidders but they never showed up to claim the TV so he kept it all this time.

I also just so happened to have scored this original Farnsworth "160-AR" picture tube last year which was one of the CRTs used in this chassis. I don't thinks that's the original yoke, but the CRT has some life left.


So anyway, I agreed to make an attempt to bring it back to life.

On the plus side,
  • The chassis looks complete and has had very little work done to it
  • I have a good replacement CRT
  • The copper thieves left the focus coil

On the negative side
  • I'm not sure of the chassis revision
  • No yoke
  • Missing HV cover
  • Missing some knobs (I found the volume and channels knobs in my stash)
  • Missing control cover

I've been told I can probably use a Admiral or RCA yoke of the proper deflection angle as it shares a common circuit design. THat's good becuase I have some spares I can try.

The HV cover looks very easy to fabricate.

That leaves knobs and the control panel. Here's a photo of the control area. If anyone has some spare parts, please chime in

I believe "balance" is brightness and "shading" is fine-tuning.
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Old 08-10-2014, 05:13 PM
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Here are some more photos of the TV.






They took the yoke but left the focus coil behind.


I sure hope the flyback is good.


It uses a common turret type tuner. THe power supply is similar the early RCA designs where there is a B- and B+ with a huge tapped voltage divider power resistor.

I see very little evidence of repairs.
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Old 08-10-2014, 08:13 PM
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Looking forward to your remaining videos on this one!
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Old 08-11-2014, 10:10 AM
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750155A-G1 Crosses to Thordarson Y13

750163A-1 Crosses to Thordarson Fly2
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Old 08-11-2014, 12:52 PM
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Thanks. Where dd you get those part #s from ?
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Old 08-11-2014, 03:33 PM
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The Capehart numbers are from Sams 112. Then I looked those up in my Thordarson catalog.
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Old 08-17-2014, 02:59 PM
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I got a copy of that Sams and dug up a yoke from an RCA KCS-47 chassis using a 16GP4. That has a 70 degree deflection angle just like the 16" CRT in this Capehart.

Even better, it has a 56 and 270pF cap inside just as shown on the schematic.


Best of all it fits. Here's a dry run with a 16KP4. I think I'll use a little 8XP4 bench CRT during the restoration.


I then proceeded to test the flyback, focus coil, vertical output transformer, etc. It all checks out - even the huge candohm resistors

Finally, I pulled the 5U4 and fired it up. All the tubes lit and I have about 5 volts on the 5U4 filament and ~700 on the plates.

So it's full steam ahead on this project
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Old 08-18-2014, 03:21 PM
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I cleaned out the HV cage last night and replaced the missing 1B3 rectifier. The transformer inside the cage is just for the 6W4 damper tube filament.


Then, I took a closer look underneath. The are a few deviations from the Sams but overall it matches well.

One thing that struck me though is the crazy assortment of resistor types. Lots of 30s style dogbones, some from West Germany, some odd body styles. Also some series and parallel combinations to get the right value.

This set is from around 1951 so I'm guessing it's a result of parts shortages from the Korean war and spike in TV demand.
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Old 08-19-2014, 06:29 PM
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I may have a Y-13 in my remaining stock. Possibly the other too. Let me know if you need me to look. There is a post of what I have in the classifieds a ways back. I used to post it once a year just so people would know the stuff exists, but I haven't updated in quite a while.
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Old 08-20-2014, 12:12 PM
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Thanks for the offer. I'll let you know if this yoke doesn't work out. I've been comparing this chassis the various service info sources and it's actually closer to the later Sams 160-2 than 112-3.

I'm also glad I reviewed the Riders info where I found this warning:


Of course, I had mine dressed the wrong way and corrected it
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Old 08-20-2014, 02:33 PM
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Those sure seem like tiny wires going to the plate caps.
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Old 08-20-2014, 03:17 PM
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For sure and I've been very careful around them. When this set was found, the 1B3 tube was missing and I'm amazed the cap lead hadn't broken off.

Assuming I can get this thing running again, I'll fabricate a new HV cage cover for protection.
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Old 08-22-2014, 12:00 AM
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I found this PENN TUBE branded 6AL5 in the set. Is that a clown face ?
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Old 08-22-2014, 12:19 AM
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It's always reassuring to have a Clown printed on your tubes, it suggests premium quality.
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Old 08-22-2014, 09:51 AM
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Quote:
Originally Posted by Eric H View Post
It's always reassuring to have a Clown printed on your tubes, it suggests premium quality.
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