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-   -   Purchased a 1976 Magnavox Console (edit) (http://www.videokarma.org/showthread.php?t=253885)

Eric H 04-01-2012 04:45 PM

Purchased a 1976 Magnavox Console (edit)
 
There's a 1976 built SS Magnavox 25" floor model sitting in one of the local thrifts here.

It's very much an entry level set with a Particle Board cabinet and simulated wood vinyl covering, metal brackets in the corners for decoration (though they may actually help hold the cabinet together) rotary tuned UHF & VHF, with a V-Matic Auto Color button, Price $5.00

Set looks to be in very good shape but I didn't plug it in, didn't have my Van either or I might have grabbed it for fun.

Any interest? It'll no doubt still be there tomorrow and I'll probably still be off work recovering from the Flu.

radiotvnut 04-01-2012 10:10 PM

It likely uses the T995 chassis; which, was likely the best chassis built by Magnavox. And, it will use a delta gun CRT. It's not a Zenith or RCA; but, it will make a good picture and, for $5, I'd get it if for no other reason than to save the CRT.

DavGoodlin 04-02-2012 07:40 AM

Magnavox's last good one
 
Quote:

Originally Posted by radiotvnut (Post 3031259)
It likely uses the T995 chassis; which, was likely the best chassis built by Magnavox. And, it will use a delta gun CRT. It's not a Zenith or RCA; but, it will make a good picture and, for $5, I'd get it if for no other reason than to save the CRT.

Very good set, still built in the Ft Wayne Indiana plant on Bueter road- I had one with the "touch-tune" system, the first keypad-controlled tuner. Was my main set for 17 years:yes:after I replaced the CRT. Very true RAdioTV nut , it was not quite a Zenith in the luminance/color department, but convergence and purity were spot-on.

I saw only a few issues with these sets when I carried MAG's module caddies:- cold solder joints, dirty module connectors and the "critical cap" which limits collector-emitter pulse amplitude across the horiz out transisitor, controlling HV. The same issues plagued the T809 and T815 chassis later on, even more so. I can still remember the module numbers, talk about wasted memory space....:sigh:

radiotvnut 04-02-2012 01:04 PM

I don't think you can get those 4-lead caps anymore. A few years ago, I had a 19"
T809 come in with a shorted saftey cap and I replaced it with a regular HV orange drop cap. I've also seen the ends blow off of them. When that happens, you'd better hope the internal interlock connection inside the cap breaks open or the HV will skyrocket and blow the neck off the CRT.

If I find another Magnavox with that cap, it will be replaced even if it still functions.

Eric H 04-02-2012 04:18 PM

5 Attachment(s)
Well I decided to go by again and check it out closer.

I managed to scrounge up an extension cord, plugged it in, powered it on, Sound immediately, Raster about 10 seconds later, all colors even and very strong!
Took it for $5.

After getting it home I partly removed the back to have a peek inside, very nicely built chassis, look at that industrial looking motor Starting? capacitor?!:wtf: That is OEM BTW.

Another thing about it is it's practically pristine inside, almost no dust, looks quite a bit like some of those NOS sets we've seen, this thing either came from the cleanest house in the world or it's very low hours.
I can practically smell the Bicentennial in this one (built 4/76)

I've posted the CRT number, is that a useful one?

I haven't hooked up a signal to it but I'm pretty certain it'll work OK.

It almost seems a shame to part this one out, it's so unbelievably clean inside, the outside isn't bad either, the top has some scruffing from stuff being slid around but it's plastic veneer so it could probably be cleaned and polished right out.

It is up for grabs to any collector who would give it a good home, second on the list would be a collector who needs a good tube or chassis for a better set.

Eric H 04-02-2012 04:23 PM

Well phooey, you can't see that big Capacitor in my pictures but it's there, near the power supply, Filter perhaps?.

sampson159 04-02-2012 05:05 PM

i have this same chassis in my bicentennial magnavox.i had to replace that cap too.these sets have a very fine picture and they are well built,rivaling the rca sets of that era.not a zenith chromacolor but still a very good set from the 70s.mine is high end but the chassis and crt are the same in your set.should be a good performer for you

dieseljeep 04-02-2012 09:29 PM

Quote:

Originally Posted by Eric H (Post 3031322)
Well phooey, you can't see that big Capacitor in my pictures but it's there, near the power supply, Filter perhaps?.

That cap is used in the power supply as part of the voltage regulating power transformer. It's a constant voltage power transformer.

radiotvnut 04-02-2012 10:07 PM

I've seen that cap/transformer arrangement in Zenith, Sylvania, GE, Wells-Gardner, and other brands from the mid-to-late '70's. I've seem them short in Zenith CCII sets.

I'm glad you were able to get that set.

Eric H 04-02-2012 10:32 PM

4 Attachment(s)
Here are some pics of it operating.
I did a very quick touch up of the Grey scale and convergence.

zenithfan1 04-03-2012 07:46 AM

That thing looks great, I think it would be a shame to part it out. I hope someone can give it a new home.

dieseljeep 04-03-2012 08:35 AM

Quote:

Originally Posted by Eric H (Post 3031337)
Here are some pics of it operating.
I did a very quick touch up of the Grey scale and convergence.

The T995 chassis had a lot ground locations that had to be resoldered. It would effect the convergence and other areas. It had such a large mother board, that flexing the chassis would crack the grounds loose.

DaveWM 04-03-2012 10:06 AM

indeed that set looks like a keeper, rare to find one in such good shape. I too hope it finds a good home intact. from the looks of it I would guess a low hours set from the lack of attracted dust (or a very good house keeper).

DaveWM 04-03-2012 12:04 PM

those power supplies with constant voltage PT are nice. My zenith uses one as well. It has a VERY broad operating AC voltage, and its NOT solid state regulated (at least on the 25CD56 zenith). From what I understand its a very loosely coupled trans that is run in saturation contstantly (at least within designed input voltages). the output is more square wave than sine. Also the loose coupling results in lower current flow incase something does short out. In the case of the zenith IIRC reading about it, the current was limited to about twice the normal current flow in case of a short circuit. The trans runs hot by design. The motor starting cap can be a problem, feel it and see if its getting hot. I had a sylvania with that setup, it would pop the circuit breaker after running for a few min. That cap was very hot by then. I prefer the simplicity of that over the SS regulated power supplies found on the later model (zenith that is). I remember running it on a variac from 90v to 130v with no noticeable change in vert height or horz pullin.

radiotvnut 04-03-2012 12:41 PM

Zenith used that design thru the first generation system 3's. Beginning with the 9-160 module sets, they dropped the transformer. Everybody figured out it was cheaper to use solid state regulation instead of using a large transformer.

Some of the solid state switching power supplies in TV's could be difficult to work on. The easiest SS power supplies in TV's to troubleshoot were the sets that used an
STR30xxx regulator IC.


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