Predicta Holiday restoration

[bandersen]

As for the sides, a little light sanding with 400 grit and a fresh coat of lacquer works well. No issues with finish compatibility.


Switching gears a little to the antenna. All this set had left when I got it was the plastic base. A few months back I came across this great ARF thread on fabricating one using salvaged rabbit ears.

Luckily, I have more of mine left and just need a replacement telescoping rod. Eventually, I managed to find one and it's a perfect fit

[Kevin Kuehn]

Looking mighty fine.

[bandersen]

Originally Posted by rrrhre2s

I think I am posting about the right set.

Been thinking about your restoration in the...
Predicta "Holiday" restoration p13o?

http://www.youtube.com/watch?v=UlHtGky46r4

at about 16:05 the LED Back light was staying lit for quite a while.

I believe if you connect the high side (ungrounded) lead of the LED to the high side of the filament string it would stop the strange behavior...

I tried your suggested and it works perfectly Only downside is the cap now retains a charge for a long time. I suppose I could add a high value bleeder resistor across it.

[bandersen]

I stripped and refinished the front edge and I think it's as good as I'm going to get without mixing my own custom lacquer dye.

Next up, a little clear coat.

[rrrhre2s]

Originally Posted by bandersen

I tried your suggested and it works perfectly Only downside is the cap now retains a charge for a long time. I suppose I could add a high value bleeder resistor across it.

A 100 K. 1 watt should help quite a bit.

rrrhre2s

[ChrisW6ATV]

That is looking really nice, Bob.

[ChrisW6ATV]

Another note, regarding the bad thermistor: I had a bad one in an RCA CTC-16 combo chassis. One wire was broken off, and the other one came off as I tried to fix the first side. However, I was able to scrape both sides of the disc and find usable "good" spots that would accept solder. So, I was able to repair it, and it has been fine for several years (though I have not watched the set for, say, three hours straight or anything). It might be worth trying that trick on yours.

[bandersen]

I did some searching around and found another source for replacement Predicta antenna rods - Zenith Chromantennas. Apologies to any Chromantenna fans.



Here are the patients with broken or missing rods.


Here's the inside of the Chromantenna.


I used a Dremel tool with cutoff wheel to carefully cut the plastic rod supports out. Then a sharp utility knife to trim off the support ribs around the cylinders.


The diameter is perfect, but they have a beveled shoulder while the originals are right angles. They will still work as is, but not fit quite as snuggly. I suppose they could be squared up with a file.

The newer plastic (mid 70s ?) is not as strong as the late 50s stuff but should hold up OK.


I should also point out that these will not collapse inside like the originals did. There will always but about a foot sticking out.

[bandersen]

Here's the cabinet back together. I removed the rust from the legs which also took off any remaining trace of the brass plating so they look like bare steel now.


A few years ago I picked up a Caswell brass plating kit and also one from AES. Might as well give them a try...

First up, the Caswell kit. This is a brush system where you dip a positive "wand" into a plating solution and rub it against a negative item to be plated.
Rather than use the little wall wart power supply it came with, I'm using an HP bench supply with voltage and current limiting set to about 12 volts and 1/2 amp.

Just as when I've used it before, the results look dark and irregular. Buffing will take care of that.


Hmm. After a few passes it barely has any brass color.


Time to try the stuff from AES. Wow! This stuff is great! It immediately turns a lovely gold/brass color.


Must be the Potassium Cyanide


Here are the final results after a few passes and polishing. Note that after remove the rust, the metal has lots of little pits which I did not attempt to grind out. Even so, I think they look 100% better.


I sprayed them with a light coat of clear lacquer and mounted on the cabinet.


Finally, here's a preview of the assembled set minus the CRT. I'm waiting on some new tubes from ESRC then I'll perform an alignment and put it all together.

[bandersen]

I forgot to mention that ESRC is having a dollar sale on TV tubes that ends soon. Stock up while it lasts: http://www.esrcvacuumtubes.com/dollar_days.html

Here's the electroplating solution from AES. You will need the brush and a DC power supply too. http://www.tubesandmore.com/products/S-F222

[bigaudioal]

Looks great Bob!