motorola vt-71 HV capacitor trouble
 

This christmass I acquired a Motorola vt-71 that is in very good shape and dosent look to have much work done to it in its lifetime. Today I got out my parts list for the TV and ordered all of the caps from just radios but the 6KV caps were missing in the chassis and I have seen ones with five or six hv capacitors. So now I am confused as to what I need could someone with a clear print out of the schematic of a set on hand please tell me how many it uses?

the chassis is the ts-4j from Feb 25, 1949

Thanks

Have you looked at the ETF schematic archive yet?

http://www.earlytelevision.org/tv_sc..._diagrams.html

Phil Nelson

Here's a scan of the schematic from the original factory service manual.

By the way, my TS-4J was made on February 11th 1949. Just two weeks before yours.

The TS-4J (early) uses two 0.001 and four 0.005 all rated at 6,000 volts.
The TS-4J (late) uses two 0.001 and three 0.005 all rated at 6,000 volts.

You can determine which version you have by looking at the contrast control. The TS-4J(late) has two taps with three little caps around the control while the TS-4J(early) doesn't.

Could I trouble you guys for your chassis serial numbers ? Ill add them to my little database. Thanks.

TS-4 serial # 2425 ( ??? )
TS-4 serial # 5680 ( ??? )
TS-4D serial # 16368 (Mar 17, 1948)
TS-4D serial # 23149 (???, 1948)
TS-4D serial # 23723 ( ? 24, 1948)
TS-4D serial # 24969 ( ??? )
TS-4G serial # 42021 (Jun 24, 1948)
TS-4H serial # 43109 (Aug 4, 1948)
TS-4H serial # 45354 (Jul 26, 1948)
TS-4H serial # 48691 (Aug 13, 1948)
TS-4J serial # 52186 (Oct ??, 1948)
TS-4J serial # 57234 (Dec 17, 1948)
TS-4J serial # 61454 (Jan 5, 1949)
TS-4J serial # 67607 (Jan 10, 1949)
TS-4J serial # ??? (Feb 11, 1949)
TS-4J serial # 72008 (Feb 14, 1949)
TS-4J serial # ??? (Feb 25, 1949)
TS-4J serial # 84425 (Apr 12, 1949)
TS-4J serial # 86923 (Apr 23, 1949)
TS-4J serial # 87897 ( ??? )
TS-4J serial # ??? (May 13, 1949)
TS-4J serial # 98728 (??? 9, 1949)

Here you go, Bob.

TS-4J serial# 70500 (Feb 11, 1949)

Thanks it is the late chassis so I ordered correctly. When I get home I will get the serial number for you

Hi Bob
Here's the chassis#, serial# & production# of the units I have.

TS-18 serial # 333570 (Nov 11 1949)
TS-4J serial # 52575 (Oct 11 1948
TS-18? serial # 301795 (Jun 2 1949) No chassis stamping on unit, but it matches up to be a TS-18
TS-4J serial # 68262 (Jan 26 1949)
TS-4J serial # 66171 (Feb 4 1948)
TS-4D? serial # 5932/27E90129 (Jan?) This unit has channel 1. All I can read is Jan in the lower right corner in the back
TS-4J serial # 63638 (Dec 2 1948) I have just this chassis for parts.

I hope this helps you out. Have a great day!

Bob, all five of my VT-71 sets are in FL right now and I am in MD. I wiil "TRY" to remember to get the SN of each one for you. If I don't post it here by this time next week, pls send me a PM to remind me.

BTW FWIW, when ordering those caps, you may want to order extras since shipping is now high and I hate to run out. Bet you get another VT-71 eventually ;)

Bob,

I cant find a number in that sequesnce but my VT-71B-A, ch# TS-4G is dated June 25, 1948. :<)

Dave G

Thanks I'll add that info to my list. The serial # is usually stamped into the metal chassis below the grey metal box.

I was just curious how many chassis were made of each run and when. I'll summarize my findings in a future post.

http://farm5.staticflickr.com/4022/4...5aeb70da_z.jpg

I almost forgot about this
Mine is 72421 made on Feb 25, 1949 laste ts-j4 chassis.

Thanks!

Here's mine Bob
TS4J serial: 58966 Dec. 6 1948

BoB,

Blonde VT-71B-A, ch# TS-4G is dated June 25, 1948
The serial number shows 20430, but it looked out of sequence per your list:scratch2:

TS-4? 4703 no date, no FT, cad plated chassis
TS-4J 57280 Nov 10, 1948
TS-4J 65152 Jan 7, 1949
TS-4J 79677 Mar 22, 1949

Hmm, the 'G' revision and date fit, but the serial# sure doesn't.

Thanks. It's a drag that the 1st generation chassis don't seem to have a date anywhere.

Here are some more for your list Bob. Only one of the three had an easily visible date stamp. Is this the first "4F" set to show up?

4D 14025 Mar 10, 1948

4F 29295

4J 53608

Thanks. Yes, it's the first 4F I've come across. Still no record of a B, C or E.

I think one of my two VT-71s may be a TS-4B; the other is a TS-4D I am pretty sure. Both have channel 1. I cannot easily get to their backs to check the versions and serial numbers, but I may be able to in the near future.

TS-4J 54402 Oct 6, can't make out the year..

It seems they didn't make very many TS-4B or TS-4C. Maybe a few thousand of each.

Thanks. It should be 1948.