Found aon old Zenith tv
 

Hello everybody. I just found this old Zenith b/w television. Here in Italy a tv like this one is really hard to find. I would love to restore it but there is nothing written to identify the model number or the chassis. I think this tv is from early fifties. There is a date printed on the hvt cage but i think this indicates when the tv has been imported here and checked apparently by a Westinghouse dealer. We started regular tv service in 1954. The chassis layout looks similar to the one installed on portholes but this has a rectangular 17 inches picture tube. There also is a strange chassis placed below the main one and connected via a plug and a bunch of wires. Is it perhaps the power supply?Any help to identify this tv will be more than appreciated.
Marco

What a very cool set! Especially to find one of these in Europe is a rare. Here in Spain we have a lot of later Zenith sets because Zenith had a factory in Barcelona starting in the late 1950s but something this early never comes up.

You should look for the Zenith chassis number in order to track down service information. These take the form NNLNN where the first two numbers indicate the number of valves in the set, the letter indicates the model year and the last two numbers are sequential to indicate version, etc. I can't remember offhand what letter went with each year, but I think 1951-1952 was H. The 20H20 was a popular chassis from 1952 so that may be a good place to start. World Radio History and the ETF will probably have service info and schematics for your set, either Rider, Beitman's or the Sams.

There is a guy here in Spain who sells American valves for these sets if you need any, you can find him on eBay as radio-antigua.

I suspect that it is indeed, the power supply.

Alan got you off to a good start. To find the date of the set look for
date codes on major ORIGINAL parts. It is usually 4 digit.
Example is # 3454 would be WEEK 34, YEAR 1954. Add 2 months to the
newest date & you will be real close.
When you think you found it compare the tubes used. If the same you
can use that manual. And yes the bottom is the power supply and
probably the audio output.

Ciao Zeno.
LFOD !

Looks like a 25 cycle conversion, judging by the size of the transformer (could be mistaken). If it is 25, it'll be very happy on 50/60 cycle also.

I think a few of the porthole chassis also were built with rectangular picture tubes. See if you can match the tubes and other features up to a chassis, and that should get you pretty close as a starting point. Also, if you have a tube diagram in theres, that helps too.

I’d imagine the chassis is modified for the Italian standard of the time, and may have been changed to the CCIR standard when that came in.

1951. Zenith had their last year of the porthole the same year. That set is a little odd in that Zenith actually used 1950 escutcheons behind both the larger knobs. The channel numbers were on a rotating drum, and viewed through a small window above the knob, not a round dial behind it. Zenith would likely stamp the model of the set in black ink. Look on the back of the cabinet, somewhere along the top edge.

Buongiorno Marco!
Congratulations!
I am a german collector with a lot of early italian TV sets.:banana:
Italy was a country where american companies offered there TV sets.
In Spain they were assambled inside a spanish factory.

It is possible, that it was similar in Italy.
I own a 1956 RCA portable, sold in Rome, with a sticker from the italian TV shop.
Maybe you know the italian year books with schematics?
I can try to check it out. Maybe it was sold officially (with CCIR), or somebody moved
from the USA to Italy.

Try to find an information about the voltage!
American sets have mostly a sticker inside the cabinet, with tube layout and power supply data.

Regards,
TV-collector :stupid:

Thank you very much for all your replies. Unfortunately a model number is not shown anywhere. The power cable is old and not in great shape. The plug is of american type but on it is inserted an adaptor for the italian sockets so I guess it works with 220v 50 Hz. Tomorrow I will try to switch it on. On the small chassis there is a small broken tube but the glass envelope is all smashed so I can't retrieve the number. Since tv broadcasting started in 1954 I think it was imported in this year. We had american tvs mostly from Philco, Admiral, Emerson and Dumont. Zenith were few. There was in my town (Florence) a man who imported and modified early Zenith color tvs and black and white ones but since color service started in 1977 there are very few early color televisions. Tv collector, I have several spanish assembled Zenith color tvs but these are solid state (chromacolor II and system 3). I have all the schematics even those of early televisions but those about american televisions are the original ones and do not show the modifications made to adjust them to our B/G standard.

Were I in your situation, I really don't think I'd go throwing 220 volts on it till I was really sure that it has, in fact, been somehow modified to run on 220.

Rig up a "Dim Bulb" tester perhaps? ...... :thmbsp:

Hi, I have a variac to power up tv at a lower voltage. I do not espect it to light up and work especially after more than fifty years but who knows? After all it's a Zenith.

Nice find, Marco!
I recall some of the porthole era Zenith sets were hybrid transformer/ series string? Would they be hot chassis and is this one of them? If all the tubes but the rectifier are 6.3 V heaters, then this is unlikely.

I don't think this is one. The hot chassis models were weird in that the top panel of the chassis was hot, but the sides weren't and there was an insulator where the chassis top meets the sides.

It's possible it might work...I have a 1951 Zenith porthole and when I got it circa 2010, ignoring 2-3 60's orange drops and some tubes, it was all original and worked just fine. I eventually recapped it so I can use it regularly.

"The plug is of american type but on it is inserted an adaptor for the italian sockets so I guess it works with 220v 50 Hz." Sounds to me like someone blew the crap out of that set before you got to it.

Likely the closest schematic to what you have.

https://www.ebay.com/itm/35450898928...85zmpu2KrVzZR8

Thank you John, I bought the service manual you suggested. The appearance of the pictured tv is very similar to mine. I attempted to connect it to power for a few moments. It makes a hum noise and some tubes light up but nothing more than that. I will wait for the schematic to see things more clearly. Thanks again!