Starting on a 1961 Zenith SC B&W

[Eric H]

I've had this set for a few years now, got it at Goodwill and stashed it in the garage till now, it's a 1960 or 61 model, nice condition, and a Limed Oak finish.

I tested the CRT when I got it and it was excellent, the set had no vertical sweep however.

I got it in the house and started taking the chassis out (checked the Vert Osc/Sweep tube first-OK) holy cow, what a PITA this is to take apart!

There are cables running everywhere that have to be unplugged, some of them don't unplug and you have to unbolt the controls from the bezel and unhook the cables from all the various wire clips and take it out with the chassis.

The CRT bolts to the chassis but it also bolts to the front bezel, not difficult to do but an extra step. After I got he chassis out I removed the CRT and stashed it inside the cabinet for safekeeping, I hope the 8" test CRT can handle the HV for a 23" tube!

I took a look underneath the chassis after I got it out, the trouble was easy to spot, it uses Bumblebee Caps all over the place, particularly around the Vert tube.

This is one set I want to get right before I put the chassis back in, Repairmen must have hated doing a service call on these back in the day!

Last picture is my assistant checking it out.

[Eric H]

OK, the restoration is done <lol>

Actually all I did was spray out the pots and take inventory of any special caps I'll need (one .015@1000v) then I fired it up on the bench to see what's what and it just worked, so typically Zenith.

It made some arcing and snapping around the yoke area at first, I though because the CRT has no Dag coating, but the Vertical jumped in and out while it was doing that, finally settling down and staying working.
I don't know what fixed it but I still plan to recap it, it works perfect though with very strong sound from it's 6BQ5 output tube.

The remote receiver is working too, I can command the channel up/down and Mute, the On button on the remote is broken so I had to operate the relay by hand to get it started.

[Eric H]

One odd thing about this chassis, it uses a 3DG4 Rectifier tube, looks similar to a 5U4 but it draws a massive 3.8 amps of heater current!! No wonder the transformer has heat sink fins on it.
That's probably more amps than most sets use as a whole.

[DavGoodlin]

The 5U4 has a 5-volt filament and 3 amp draw but peak rated for 1 amp per plate, thats 15 watts just for the heater!

3DG4 is a 3.3 volt filament but rated at 1.2 amps per plate, so you get more for less heater W.

PM me if you need any factory info for the SC. I have a good Zenith collection from 57-64

[wa2ise]

Originally Posted by Eric H

Last picture is my assistant checking it out.

Check out this thread over in AudioKarma, cats and audio equipment, similar to your kitty and TV set.

http://www.audiokarma.org/forums/sho...highlight=cats