Motorola VT-71 (TS4H)
 

I have restored several radios in the past and I'm finally comfortable enough to dive into this VT-71 I picked up at a funky clothing store in Las Vegas 7 years ago. Its sat at my mothers house until the day came I wanted to restore it.

http://i65.photobucket.com/albums/h2...1/100_2840.jpg
http://i65.photobucket.com/albums/h2...1/100_2841.jpg
http://i65.photobucket.com/albums/h2...1/100_2852.jpg The set is in pretty good shape and is complete aside from it missing the metal back cover and the aluminum bottom plate. I just ordered a set of capacitors for this television from JustRadios last night. http://i65.photobucket.com/albums/h2...1/100_2862.jpg http://i65.photobucket.com/albums/h2...100_2858-1.jpg[IMG][IMG]http://i65.photobucket.com/albums/h2...100_2864-1.jpg[/IMG][/IMG]http://i65.photobucket.com/albums/h2...100_2860-1.jpghttp://i65.photobucket.com/albums/h2...1/100_2854.jpg
On top of the capacitors I plan to replace the selenium rectifiers, out of tolerance resistors, any bad micas and I want to replace the ballast with the panasonic capacitor setup posted elsewhere in this forum. I just hope the 7JP4 is still good.

You may want to check out these threads when you get a chance.

http://antiqueradios.com/forums/viewtopic.php?t=134239

http://antiqueradios.com/forums/viewtopic.php?t=124246

http://antiqueradios.com/forums/viewtopic.php?t=103616

http://antiqueradios.com/forums/viewtopic.php?t=109379

http://antiqueradios.com/forums/viewtopic.php?t=110760

http://antiqueradios.com/forums/view...p?f=3&t=155458

If you need new decals for the front, I have a few sets for the cost of postage.

Coincidentally, I'm just wrapping up refinishing one of these cabinets. I'll post some pictures in my TS-4H thread soon.

Good luck with the capacitor ballast. I'm curious to hear how they work out. I went with a glass Amperite one and they do get quite hot.

That is a generous offer that you made to fox_rivers. I hope you can send them to him.

Did you make the decals or did you buy them? The reason I ask is because I have 5 of these little guys, one is blonde, and I will eventually need some. But I am not trying to drain your supply. If you make them, I would like to compensate you for some you can. If you bought them please let me know where you got them.

I have restored one of my 5 so far and have not done the cabinet yet. I got the CRT mask from Ed (Blacksmith). If someone has his website, please post a link. I can't find it right now and have to run.

BTW, another reference.

http://antiqueradio.org/motvt73.htm

And two threads that I did.

http://antiqueradios.com/forums/viewtopic.php?t=144209

http://www.videokarma.org/showthread.php?t=248722

And here is Bob's

http://mail.videokarma.org/showthread.php?t=245840

You can get the gold decals from these places

http://www.radiodaze.com/product/6081.aspx

http://www.radiolaguy.com/MotorolaVT71bk.htm (scroll to bottom)

The blonde set uses dark brown decals rather than gold. No one makes those so I made a custom set myself and could make more if anyone needs some.

Here is the gentleman that makes reproduction CRT foam mountings for the 7JP4 in the Motorola VT-71. His name is Ed Schutz and this is his website:

http://www.renovatedradios.com/parts.html

Thank you miniman82!

You guys are so helpful and kind! Thank you!

No problem, this is what the community is for!

Coincidentally, I also bought that repro CRT mask for my set and while it is expensive, you can't really do a proper resto without it. I recommend buying one, since the original is always melted to the CRT. I still need knobs for mine, but am holding out for a used set because I refuse to pay $40+ for 4 pieces of plastic.

I'll hold off on the mask till I can afford it. For the meantime I'll make something temporary out of some sort of foam.

I feel the same way about the mask as you do the knobs. I know the reproduction masks are difficult but still....its just foam to me.

Thanks for the info Bob. I should just get them and have them "In Stock". I think the blonde cabinet is in the best condition and the markings may be still OK.

I wanna refinish the cabinet at some point in the next couple of days. Whats the best way to strip and refinish it? I've heard in the forum that its best to use a hand rubbed lacquer. What products and methods would you guys recommend to accomplish all this?

Here's what I used.

Zinsser Magic Strip Citrus-Action Gel follow by Zinsser After Wash to strip off the old finish. CitriStrip works great too.

Minwax Mahogany Gel Stain.

Constantine Mahogany paste grain filler

Deft Sanding Sealer

Mohawk Brown Mahogany Ultra Classic Toner Lacquer. That's to make the top and bottom strips a little darker than the rest of the cabinet. That's how the original finish looked on mine.

Finally, Deft gloss lacquer. After it cures for a few weeks, I like to rub out the finish with #0000 steel wool then pumice and rottenstone abrasive powders. You can just stop with the steel wool for a satin finish or pumice for a semi-gloss.

That probably sounds like a lot of work and stuff to buy, but you'll end up with a great looking authentic finish.

We should rename the website TV SHAMBALA.:D

I really like your method. It may be alot of stuff to get but it will be well worth seeing that cabinet looking like new.

What kinda diodes should I use to replace the rectifiers?

General purpose silicon rectifiers, even cheap Radio Shack ones are good enough.

1N4007 are rated for 1000 volts @ 1 amp and cheap. I keep a bunch on hand for replacing seleniums.

In the meantime while I wait on parts in the mail I thought I'd shine up the chassis. :) http://i65.photobucket.com/albums/h2...1/100_2878.jpg

Sweet :thmbsp: Word of warning though. I polished up a section on one of my copper chassis and it tarnished after a couple weeks.

Be sure to get the Brasso out of those tube sockets. Better to mask them. Try some car paste wax on top of the Brasso to retard tarnish.

I'll try some turtle wax then. I figured since I had to clean the tube sockets anyways that I wouldn't bother masking them off but I was still careful about not globbing it in the sockets.

I didn't polish the rear of the chassis because I'm sure I would have took off the labeling for the picture adjustments.

Ok, well got all the parts aside from the electrolytics. My 1B3GT Tested bad so I had ordered a replacement. what I got was a 1B3GT but its much shorter then the original and the placement of the coil around the tube wouldn't be correct. Did I order the wrong tube for this set?
http://i65.photobucket.com/albums/h2...52-17_3831.jpg

Nope, newer 1B3s are just shorter. When you slide the feedback coil over it, it will need to be a little lower than it was on the taller tube.

Oh good. Well hopefully those electrolytics come in tomorrow so I can get started on this set. Of course the first thing I'd have to replace would be the last to come in the mail. Hah!

There's a note in the Riders manual and Sams for this set about spring placement between the 2 different styles of tube.

Right. It should show placement of the feedback coil on the older 8016 and then the 1B3GT. I'll just place the coil below the metal band in the tube as it shows for the 1B3.

Still waiting on those pesky electrolytics and how impatient I am I figured I'd rebuild the ballast and replace the HV caps. http://i65.photobucket.com/albums/h2...1/100_2919.jpghttp://i65.photobucket.com/albums/h2...1/100_2921.jpghttp://i65.photobucket.com/albums/h2...1/100_2923.jpg

Please show us how you rebuilt that metal ballast.

I ordered a pair of Panasonic ECQ-E2106KF 10uf 250v film capacitors, a 200 ohm 5w and a 30 ohm 5w resistor from Mouser. http://i65.photobucket.com/albums/h2...38-02_9151.jpghttp://i65.photobucket.com/albums/h2...-06-43_957.jpg I removed the innards of the old ballast and desoldered the copper leads from the pins using a solder sucker.http://i65.photobucket.com/albums/h2...1/100_2916.jpg I placed the resistors on a piece of PCB I cut out of an old power supply and I used this schematic to wire the caps and resistors to the base of the ballast.http://i65.photobucket.com/albums/h2...placement2.jpg I spray painted the metal can for the ballast black and installed the newly rebuilt unit into metal can thus looking awesome.

Does it generate a lot of heat in operation? It looks like a good solution, one of several ways to deal with these old ballast tubes.

This ballast will run 80% cooler and eliminates the current surge when the set is powered so it will prolong the tubes as well as the 7JP4. This thread explains more about how they work. http://videokarma.org/showthread.php?t=249434

Neat fix, but I prefer the glass ballast.

I have to admit, the glass ones do look cool.

The glass ballasts run just a little cooler than the metal ones and I suspect they are more reliable since they are under vacuum. I am using a glass ballast in my Motorola with good results. I would like to build one of the alternative types as a backup.

I'm delighted you chose to use the cap balast I described back in Nov 2010 for your project. They are still working great for me.

For best results, it may be necessary to tweak the 30ohm resistor lower to get correct filament voltages. This is due to normal tolerances of the caps.

This is easily done at the socket, by connecting a 2w resistor of between 100 and 300 across pins 1 and 6. You can always change out the ballast R later with the newly established value.

Note: To get stable filament voltage measurements, you need to wait at LEAST 5 minuets from a cold start.

I really liked the idea of the soft start as well as it looking original. I appreciate the tip and the build design. :)

Well I finally got all the electrolytics replaced and the 2 diodes in the power supply. I put a 40watt bulb in line to limit the current to the set. Flipped the switch and nothing, no power. :( I took the bulb out of line and still the same.

I went through all the caps and everything and it all checked out so the only thing I suspected was the ballast and sure enough the ballast schematic i used was incorrect for my tv. Pin 5 which was one side of the ac line wasn't used so I have to figure out which parts in the ballast go to what pins. I'm not exactly sure how I'm gonna figure that out.

The VT-71 had more revisions than I've seen in any TV or radio.

Phil Nelson