1948 (TS-4H) Motorola VT71 restored!
 

zenithfan1 inspired me to post a little photo diary of my VT71 restoration.

Enjoy.


Arrival. It's in good shape aside from all the knobs being wrong.
http://www.bobandersen.com/images/TS4H/s001.JPG

Pretty much all original.
http://www.bobandersen.com/images/TS4H/s002.JPG

Ugh. Need to re-solder a CRT pin.
http://www.bobandersen.com/images/TS4H/s004.JPG

Apparently, this is the melted CRT mask. It hit a few tubes and the speaker
http://www.bobandersen.com/images/TS4H/s007.JPG

I really hope I never need to do this again!
http://www.bobandersen.com/images/TS4H/s008.JPG

Refinishing the cabinet. Citristrip is my favorite stripper lately.
http://www.bobandersen.com/images/TS4H/s009.JPG

Applying new decals from radiodaze.
http://www.bobandersen.com/images/TS4H/s013.JPG

The usual. Replaced the selenium with silicon. Wax caps with poly. And HV caps from Allied.
http://www.bobandersen.com/images/TS4H/s018.JPG

Ready to fire up. Got those knobs from a blonde VT71.
http://www.bobandersen.com/images/TS4H/s019.JPG

First signs up life using a 7VP1 CRT from an RCA WO-56A scope.
http://www.bobandersen.com/images/TS4H/s020.jpg

Seems safe enough to hook up the 7JP4
http://www.bobandersen.com/images/TS4H/s021.JPG

Old components. Those two caps in front were the source of much hair pulling. They came from the vertical oscillation/sweep circuit.
I assumed that mica caps rarely go bad. Boy was I wrong.
http://www.bobandersen.com/images/TS4H/s022.JPG

Replaced the 12AT7 and got my 1st stable image
http://www.bobandersen.com/images/TS4H/s023.JPG

Here it all is back together. I still need to track down a fine-tuning knob and do something for a CRT mask.
http://www.bobandersen.com/images/TS4H/s031.JPG

Here's some of the gear I used.
http://www.bobandersen.com/images/TS4H/s040.JPG

Great post,, loved it!!!

Very nice, that stuff isn't foam however, it's the infamous VT-71 mask that is always melted, it's water soluble, not that that's any help when it's on a speaker cone!

Renovated Radios makes a repro mask now for about $43.

Wow! They can really melt all over like that? I guess that makes more sense than a maniac with an insulating foam canister :o

Looks great ! , the VT-71 is next on my list to get .
They sure look like a fun set to restore .

So how long did it take from start to finish ?

Nice job! It looks like the crt was in good shape also as you dont see many with a perfectly centered picture. I hope to do both of mine soon!
-Tony

The chassis is clean & purty enuff to be left out of the case...Great job !

Nice job. Especially like the way that cabinet turned out. I'll have to try that citrus stripper

Beautiful job! It looks new! Thanks for sharing, I'll have to try that stripper too.

About a month working ~ 2 hours a night. Would have been a week less if I had replaced those mica caps from the start!

They changed the formulation recently and it's even nicer now. It leaves your place with a nice smell of oranges :)

Thanks! I went a little nuts on cleaning up that copper :o

Which was the one of these little guys that the mfger had to be "cute" & used an 8" CRT ? I thought it was Motorola...

Thanks. Here's the stuff I used. I like Behr - it's all water soluble.

Yep. They made a few models with an 8" CRT. I haven't found any yet.

http://www.tvhistory.tv/1949-Motorol...kelite-8in.JPG

End of analog TV in Chicago
 

My Astro Dog antenna can still pull in WGN in chicago :D Last man standing.

That's a cool set. I had one of those over 20 years ago. Got it free, found a NOS CRT for it for $38, and got it running. I was in High School at the time.

I ended up selling it to a teacher, of all people, for $600. Well, he did beg and plead for a year to buy it.

Memories...

To think I was 17 when I repaired that Motorola. And then there was the Muntz set...

I had a blast in HS too. I was lucky enough to have the 'electronics' shop class all 4 years. 1st year was house wiring. 2nd year a little tubes then all transistors. 3rd & 4th years - work on whatever you wanted. This was the early 80s though so I ended up making a 'new wave' electronic drum kit :guitar:

I built my own Pay tv decoder in HS as an electric shop "project" :D

The thing worked GREAT!

Sometimes I miss those days. There was so much wonderment for electronics.
Fixing old TV's was a lot of fun, and I learned a lot.

Working on this digital crap with ROHS compliant boards you can't really solder on has really taken the charm out of the hobby.

There's NOTHING like a good tube set. :thmbsp:

Oh man, I'd forgotten about those :D I think RadioElectronics published instructions or maybe I got them mail-order? I thinkd they called it a sync-restorer. Mine only worked so-so, but loads of fun. I kinda miss looking cross-eyed at the squiggly video :tongue:

[QUOTE]Working on this digital crap with ROHS compliant boards.../QUOTE]

Is that the crap without lead? I've noticed my 20 year old solder works better than new stuff!

It was an ON-TV decoder. I used 1% tolerance parts. The thing was rock stable.

Well, didn't mean to hijack this thread, though. I'll miss analog. It has given me many good years in the hobby.

Restoring a vintage set will feel different now, without native content to watch on it.

NP. There are a couple Motorola VT71s and a suitcase on eBay right now.

I did a little test with my Blonder Tongue BAVM-z. I attached my DVD player to the input and a short wire to the RF output. I picked this up on the VT71 about 40 feet away.

There are a bunch of these on eBay going for about $10.

Dr Who anyone?

http://www.bobandersen.com/images/TS4H/drwhovt71.jpg

Nice! I'll have to try that myself!

Here's what they look like. The BAVM-z has a hardwired output channel. You can adjust the input audio and video levels and the RF output power.

The 'Agile Modulator' line lets you change the output channel on demand.

You might need some female RCA to co-axial adaptors to hook it up to your existing gear.

I have got to get some of those, I haven't found any yet. Probably looking at the wrong times. I wanted to build a multi channel output using those and a combiner like a friend of mine did so the Space Command sets can work other than getting cable. This way I could use converter boxes on my favorite channels plus a channel for DVD or whatever.

Great stuff!

I'm surprised the picture is that clear with just a short wire off the modulator. What antenna is the moto using, is it still hooked to that "astro dog," or are you using something larger. And the 2nd doctor is my favorite, it's too bad they lost so many of his stories. I've got 4 of these motorolas sitting in the attic awaiting restoration.

Good job! Looks very nice!

Gohan

I switched to a proper set of rabbit ears. The astro dog is actually a pretty lousy antenna. I used a vertical wire about 12 inches long on the modulator.

Troughton is my fav too. I've been watching the whole series (recons included) from the very beginning. I'm up to Moonbase :)

That's good work, Banderson.

Your Troubleshooting Skills are better than mine...

LJB:smoke:

I wish I knew how to work on TVs like that, but I'm too damn stupid to figure it out...I'm serious. I NEVER COULD make head nor tail out of basic electronic theory, & I've studied it, had people try to "splain" it to me, watched instructional videos...The whole 9 yards...It's like there's a 10' high wall there that can't be breached...Its like its worse than Chinese Algebra or some damn thing...I am in utter AWE over you wahoos who CAN & DO work on 'em, & can make 'em "shine" like that..My hat's off to you..But I'm still not 100% convinced that electronic theory, watts, volts, amps, capacitance, resistance, diodes, triodes, etc, all that stuff is a bunch of made-up hooey to keep us peasants in utter thrall, that Electronics really IS actually magic, & all youse byrds are really wizards 'n' warlocks, practising your arcane & black arts...

For a long time, I ignored micas in the belief that they were almost always good. I learned different on my 630TS when a pal tipped me about checking a couple in a known trouble area.

Like many other 60-year old things, micas are starting to show their age. I don't shotgun them without testing, as I do paper caps, but I'm alert that they don't all stay perfect forever.

Nice job. I'm a Citri-Strip fan, too. And I will even forgive you this time for using polyurethane <holds up garlic, makes sign of cross> :)

Phil Nelson

I looked for modulators and found a few. Thanks, your post reminded me to keep looking for them. The last time I checked the bay a few months ago I found none and forgot about it.

This was actually the 1st time I ever used it. I decided to give the whole line of Behr water based products a try on the project. The results are OK and cleanup was a snap, but it's not as good as more traditional products.

I've used hand rubbed tung oil and spray lacquer in the past. What do you recommend?

I dunno about all that :scratch2: Although I do have a BSEE, I got all my practical knowledge from hanging around hamfests, forums like this and a whole lot of tinkering.

I think it just takes time to sink in. Hopefully, it will all make sense to you soon.

Normally lacquer -- the same thing originally used for the majority of old radio and TV cabinets. Easy to use, dries fast, and can be reversed if you don't like the outcome and want to start over. Poly can provide a very shiny finish, but if you've ever tried to strip it, you'll know why it's not my favorite.

Phil

Wizards 'n' warlocks, practicing arcane and black arts?

Just take a look at Phil Nelson's avatar (above in this thread). I think there is your answer! :D

Actually, it does take some time --and a GOOD teacher or book (some are impossibly obtuse)-- to catch on. Give it time and keep trying, if it matters to you. Eventually, you'll learn it.


As for the restoration that is the topic of this thread, man, that is beautiful! Very, very nice to see that people are continuing to restore these old sets even in the face of the death of analog, and a quality job like yours is an inspiration to all of us who restore anything. Thanks for sharing it! :thmbsp:

Incidentally, if anyone has sets like that one which they don't want anymore since there are no more analog broadcasts, there are people in other parts of the world like Hong Kong, who can still use them to receive analog TV broadcasts over the air. I don't mind taking charge of seeing that they find good homes, if you send a few those smaller sets to me! :D

Back on topic (:D), I use a citrus-oil based cleaner, which, while it can partially strip very old finishes if you work it hard enough, wasn't designed for stripping. Think I'll try the stripper version next. The citrus smell is sure a LOT nicer than that horrible, toxic smell that most commercial strippers have. I used some commercial stripper on some vintage (metal) fans recently, and despite pretty good ventilation, felt sick afterwards. (:puke:) :nono: :thumbsdn:

I've tried using Watco spray lacquer a few times, but had trouble with runs. That's why I tried wipe-on poly with this project. I just picked up a can of lacquer to try brushing it on with my next project.

I had concerns sbout stripping the poly too, but CitriStrip takes it right off - no problem.

Don't think I've seen the 'puke' emoticon used before :)
I believe Methyl Chloride is the nasty stuff in commercial stripper. I sometimes use it after the CitiriStrip to remove any last traces of goo.