Silvertone 8106 - Videokarma.org TV - Video

Doug66 · #1 11-20-2014, 10:10 PM

I picked this up off my regional Craigslist last week and thought I could do a quick restoration on it. However, when I took the back off tonight, I was greeted by the following: see pics. It looks like the yoke cover melted. This is as far as I've gotten.

Phil Nelson · #2 11-20-2014, 10:53 PM

As awful as that looks, it's possible the yoke may still be sound. Some covers were made of a miraculously cheesy plastic that self-destructs. I haven't seen one quite that bad before, but I have seen covers that were warped all to heck, with pieces falling off, etc.

I would withhold judgment for the time being. If the yoke turns out to be OK and you finish the remainder of the project, you can fashion a substitute cover later on.

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

wa2ise · #3 11-21-2014, 02:56 PM

Is that a Philco style circuit module (top center of the picture)?

Maybe Philco made this set for Sears...

Findm-Keepm · #4 11-21-2014, 03:28 PM

Quote:

Originally Posted by wa2ise

Is that a Philco style circuit module (top center of the picture)?

Maybe Philco made this set for Sears...

Couplates are not specific to Philco. RCA, GE, Motorola, and others used them as well. This set looks like either a Warwick or Westinghouse to me.

robert1 · #5 11-21-2014, 03:42 PM

Quote:

Originally Posted by wa2ise

Is that a Philco style circuit module (top center of the picture)?

Maybe Philco made this set for Sears...

Warwick Electronics of Chicago built this set.
Also, It Is not a "Philco" style circuit module, it is referred to as a "Encapsulated Circuit Module". there were two manufacturers that made these "E.C.M's" Centralab & Erie. the red modules were built by Centralab. these were used by many electronics manufacturers during the late fifties all the way up to the early seventies.
Both Centralab & Erie Would build these to manufacturers specifications. these were mainly resistor / capacitor circuits.

robert1 · #6 11-21-2014, 03:26 PM

Quote:

Originally Posted by Doug66

I picked this up off my regional Craigslist last week and thought I could do a quick restoration on it. However, when I took the back off tonight, I was greeted by the following: see pics. It looks like the yoke cover melted. This is as far as I've gotten.

This was a common ocurrence with these yokes from the 50's & 60's. the material used to make this plastic like cover would deteriorate because of heat. the deflection yoke should be Ok. the problem with these plastic covers is that they also hold the centering rings in place. when the plastic cover deteriorates, you will not have any way to center the picture.

Doug66 · #7 11-21-2014, 05:01 PM

I've gotten the chassis out of the cabinet and cleaned up the mess. I'm wondering if one of the electrolytics shorted causing it to overheat. The 1st one pictured looks to be oozing its insides. It's a 5 section unit. haven't seen one that big before.
The 2nd electrolytic is one that I've never encountered before. It has a positive and negative at both ends. Normally, dual or multiple units share the ground.
Yes, this set does have couplates. I took a pic of the largest one, 15 components. I've watched bandersens Predicta restorations, and I've used his techniques to rebuild the couplates in a Philco Briefcase I recently restored. I'm also currently restoring a Predicta and will be rebuilding the couplates in it within a week or so. However, I hope I don't have to do that in this set. It has a 15unit, a 13 unit, and an 11 piece unit.

old_coot88 · #8 11-21-2014, 08:01 PM

Quote:

Originally Posted by Doug66

The 2nd electrolytic is one that I've never encountered before. It has a positive and negative at both ends. Normally, dual or multiple units share the ground.

It's actually two separate, unconnected caps. One is the doubler input cap, IIRC.
The first time I ever replace one of those, I (mistakenly) thought the red lead coming out one end went with the black lead coming out the other end, and proceeded to wire it accordingly.

The dang set came on and worked, but with humungous hum bars and hourglassing.
I quickly corrected the goof.

Doug66 · #9 11-25-2014, 06:54 PM

I finished replacing all the electroltyics today aw well as the two rectifiers. I tried a power up with my Variac. Not very good results. Tubes lit but no sound no raster. Unfortunately this set is one of those where the chassis is a square with a cutout in the center for the CRT which stays in the cabinet as the yoke can be unplugged. To make test on the underside, I'll have to pull the yoke off the CRT and use my test CRT.

Electronic M · #10 11-25-2014, 11:23 PM

This is where having a test jig with a 'universal' yoke becomes rather convenient.

Doug66 · #11 11-26-2014, 12:36 AM

Well, after my last posting, I pulled the yoke off and hooked up to my 5" test CRT. I was rewarded with a raster but still no sound. Either something is amiss with the correct CRT in the cabinet or I turned up the wrong control for brightness when I made my initial power up. The controls aren't labeled, and I don't have a Sams for this set. Hooking up a signal gave me a pic, but I couldn't get the vertical to sync. Right now I'm recapping the sync board.

I'd like to know who built this set for Silvertone. I've already had one PC trace lift up on the sync board despite how careful I was. Even though the Predicta I'm also working on was a pain to recap, I didn't have 1 trace lift up during it's recap.

robert1 · #12 11-26-2014, 01:09 PM

Quote:

Originally Posted by Doug66

I'd like to know who built this set for Silvertone.

Warwick Electronics of Chicago built this set for sears.
i stated this in a earlier post.

Doug66 · #13 12-05-2014, 08:04 PM

I've got all of the capacitors replaced. That allowed me to lock in the vertical temporarily. The audio output transformer was open, so I replaced that. Now I have bad sync in both horizontal and vertical. I've subbed new sync tubes and replace the resistors in the sync circuit. It starts as a wavy pulling at the bottom of the screen hen travels up to the top. I cannot get that straightened out with the horiz hold. The vertical also loses sync too. This set is so simple, I can't figure out what I have overlooked.

dtvmcdonald · #14 12-05-2014, 08:57 PM

With that symptom one always worries about a bad AGC resulting
in very compressed sync pulses. Scope the video.

Tubejunke · #15 12-06-2014, 12:24 AM

Quote:

Originally Posted by Doug66

Well, after my last posting, I pulled the yoke off and hooked up to my 5" test CRT. I was rewarded with a raster but still no sound. Either something is amiss with the correct CRT in the cabinet or I turned up the wrong control for brightness when I made my initial power up.

See if the heater inside of the original CRT is lighting up. Many sets have loose CRT plugs and the pins often had poor soldering from the get go, so things start moving around and you get intermittent connections. If the plug is loose, then you can move it gently and the heater will light up, or should. You can then re-solder the pins and re bond the plug to the glass with a suitable adhesive. CRT rebuilders' of late used a silicone based material, but I'm not sure exactly what it is.

Either way, you don't want to leave a loose plug that way because you will eventually break a conductor possibly at the glass and you will be really messed up....