1949 Arvin 3120-cm - Videokarma.org TV - Video

bre's dad · #1 05-07-2007, 02:06 PM

Just picked up an old Arvin console tv at a yard sale. More like stole it... paid the guy $5. He's a collector and domestic management said he goes or the TV's go, hence the yard sale. Its a model 3120-CM, Chassis # te-272-2. When you plug it in & turn it on, it starts the usual popping & crackling, but after about 10 seconds the cord heats up & pops the breaker. Granted, the cord is in bad shape but any ideas?

I know an old ham/tube everything guy who used to work on these and still has the equipment (and probably the schems for it.) He's worked on similar ones and said its probably an easy fix, but doesn't have the time to look at it. I walked into an old tv repair store and told them what I had. The kid at the counter didn't know what the hell I was talking about... b&w tv? He refered me to the owner who smiled and laughed. Said he hadn't worked on a tube tv in about 10 years, though he was familiar with the old Arvin lilnes. He shoed me his personal collection in the back and had one similar.

blue_lateral · #2 05-07-2007, 04:04 PM

IMHO theres a short on the b+ line, probably a filter capacitor. It probably has a tube rectifier, and when the tube gets hot and starts conducting, it blows the breaker.

Without a schematic, thats a wild guess.

John

kbmuri · #3 05-07-2007, 07:41 PM

BD -

This is a great set. Parts can still be had for a song, and it's not overly complicated to work with. You've come to the right source for advice. You should start by searching this forum (Early B/W sets) for the keyword "recap". A wealth of data will flood back to you. The first impression you'll get, is, "don't plug it in and let it start popping and crackling and heat up the power cord", but I guess everyone learns this, one way or another.

"Indiana" is a big state. I could recommend a repair shop in Southern Michigan who would repair it for you, correctly, for a price. PM if interested.

bre's dad · #4 05-07-2007, 08:59 PM

Everyone tells me not to turn it on & let it pop. Keep in mind I did that only once.

truetone36 · #5 05-07-2007, 10:20 PM

Once is all it takes to possibly do serious damage to important and VERY hard to find parts (flyback, power transformer, etc.).

We have all done this at some point though. You definately should replace all paper and electrolytic
capacitors as these are most likely dried out. Shortly after I began collecting t.v.s I blew the transformer in a beautiful Dumont console.

Dumont-First with the finest in television.

***Eric H*** · #6 05-07-2007, 10:27 PM

Just to clarify, is the breaker that's popping on the set or the breaker in your house?

If it's your house breaker popping there's a serious short somewhere, I don't think a short on the secondary side of the transformer would pop a 15 amp breaker but one in the cord or the primary of the transformer would.

bre's dad · #7 05-07-2007, 10:58 PM

ok, more clarification:

Understand the potential of damaging the set on the first try. The guy I got it from never plugged it in. It was sitting in a pile of stuff he had aquired some time ago but never had the chance to go through to test. Had to start somewhere and plugging it and turning on is in my logic.

The breaker that popped was on an outlet strip, not a breaker in the house, which would be hard given that I still have a fuse box (talk about old school), but the fuse box is a totally different issue on the list to get upgraded.

The sound I heard coming from inside the set is very similar to the sound my old National shortwave makes when it first comes to life and similar to the old tube console stereo I used to have. Both of them worked great. Had the shortwave restored & recapped by my friend several years ago when he actually had free time.

The tv may be fried beyond repair. I hope not. Either way, its not going to end up like many like this do as a fish tank, funky computer case mod or something really stupid, like well, gutted. It will happily sit int he corner as long as my wife doesn't make me get rid of it. She wasn't happy when I told her I bought it, regardless of the price (thinking it was a clunky console tv from the 70's), but was intrigued and thought it was 'cute' when she saw it.

bgadow · #8 05-08-2007, 11:37 AM

Arvin TV sets aren't the most common (but it was born in Indiana so probably more common there). That sets a keeper. It would be nice to be able to test the picture tube, but probably not the end of the world even if it's bad. I say chances are very good that recapping it will bring it at least most of the way back. Good luck!

bre's dad · #9 05-14-2007, 07:44 AM

my dad, who is more qualified than me to work on this thing (used to be a old tv guy) looked at it over the weekend. Looks to be one or more filter capacitors are bad. He pulled the power rectifier tuber and everything that was supposed to light up did w/o tripping the breaker on the outlet strip. And yes we did replaced the ac cord (was frayed pretty bad, but not shorting out.)

Does anyone know where I can get schems for this? The local tv shop, which has been around since the dawn of time hasn't worked on any tube gear for over 10 years and doesn't know where to order parts. There are no small electronics shops around anymore here, other than a small radio & commercial electronics outfit, but they donn't do work for the public.

I'm not a tech, though if I know what all needs replaced I can do that. If we had a set of schematics for this, it would greatly speed up the repair time & process. My dad doesn't have alot of time to put into this. The other old tube guys I know don't have time for their own stuff.

bre's dad · #10 05-14-2007, 07:47 AM

Quote:

Originally Posted by bgadow

Arvin TV sets aren't the most common (but it was born in Indiana so probably more common there). That sets a keeper.

The interesting thing is I've got a good idea what building this was made in. Though abandoned now (not much of Arvin left in Columbus), there is an old factory/warehouse building that Arvin used dating back to the 40's that was recently a flea market. It is one of the older Arvin buildings, though I don't know exactly what was made there. Ironically, its not far from where I live.

Einar72 · #11 05-14-2007, 09:29 PM

The schematic is easy to find for most TV's of that era. You can probably find Howard Sams' Photofacts at your local library, unless they have disposed of them. I didn't see your number listed in their online index, but there may be another number on the unit. It also may turn up in Beitman's Most-Often-Needed schematics for its year. Maybe Rider's TV, one of those will probably have it. Bring both model and chassis information with you.

As far as parts go, you can order online from Antique Radio Supply, Mouser Electronics, Allied Electronics or my new favorite, Triode Electronics where you can get REAL Orange-drop capacitors and killer deals on NOS tubes (especially series-string TV tubes). It's worth the time to find the same brands (if still around) that were used, but with some parts, you will have to settle for whatever passes for "parts with wires out the ends", since they are seldom used nowadays!

John Folsom · #12 05-14-2007, 11:47 PM

To fault isolate you problem, try this: Remove the rectifier tube (likely a 5U4), and try teh set again. If it still pops the outlet strip breaker, you have a short on the AC primary side of the transformer, or on the secondary filament string, or in the transformer itself. If the tubes light up and no other "bad" symptoms, the fault is likely downstream of the rectifier.

Tim · #13 05-15-2007, 02:00 AM

I have a duplicate of the Sams folder for your set, 80-2. PM me your address and I'll send it out.