Philco Prewar Console Television

[dieseljeep]

Originally Posted by jr_tech

Check out the schematic on ETF (scroll down to 10" Philco) looks to me like a 7B5 driving an electrodynamic speaker in the set:

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

jr

I should've have known, as the set has a speaker grill.
I wonder how many of those strange tubes used in the sweep and HV are available. I see, they also used their favorite 5X4G's in the LV power supply.

[ChuckA]

Originally Posted by dieseljeep

It looks like to me, that the HV transformer is the potted block style Behind the HV rectifier.
I wonder what they did to the audio circuit, as the Philco's didn't use an audio output circuit. They transmitted the audio to a Philco radio, around 8mhz. They must've converted the AM audio to slope detection.
Looking forward to more information on this set.

Only the small 6" table set didn't have audio circuits installed. The 1938 MIL set had audio as did the larger 1942 10" console with radio.

The 6" table model I have had audio added around 1942, for some unknown reason Philco decided to use their own version of the 6V6, a 6V5 for the audio output.



Chuck

[ChuckA]

Originally Posted by vts1134

I've written the museum where the other set is supposed to live, but haven't heard back from them. I'm hoping they can send photos of theirs. Does any one know if the set at the Philadelphia History Museum has the same cabinet as mine, or is it the other style with the wooden slats over the speaker?

DaveA is the only one I know who has seen that set when it was in the old Atwater Kent Museum. I talked to him a few weeks ago to see if he could stop by the site and see if it is still there.


Chuck

[jr_tech]

Originally Posted by ChuckA

The 6" table model I have had audio added around 1942, for some unknown reason Philco decided to use their own version of the 6V6, a 6V5 for the audio output.

6" table model pre-war Philco?? WOW!!! I have never heard of that... could you
post more info? CRT number? Was it electrostatic or magnetic deflection?

jr

[Steve McVoy]

Here:

http://www.earlytelevision.org/philco_7in_prewar.html

[Dave A]

I emailed the museum about 10 days ago to check on this and they have not answered. I saw it almost 15 years ago at the old AK version of the museum. It is now in new hands and no idea of what has happened in the attic.

[vts1134]

Originally Posted by Dave A

I emailed the museum about 10 days ago to check on this and they have not answered. I saw it almost 15 years ago at the old AK version of the museum. It is now in new hands and no idea of what has happened in the attic.

Odd timing. I emailed a week ago. I'll try to see if I can get any answers via telephone.

[dieseljeep]

Originally Posted by jr_tech

6" table model pre-war Philco?? WOW!!! I have never heard of that... could you
post more info? CRT number? Was it electrostatic or magnetic deflection?

jr

You'd almost have to swear that Philco was slightly ahead of the game!
Magnetic focus and deflection, a slightly advanced CRT design, that could easily be converted to a newer 10BP4 type.
I realize that the RCA and others had magnetic deflection as well, but the old CRT's were harder to sub.

[tubesrule]

The 9" GE HM225 and 12" GE HM226 from 1939 used short Philips crts that were magnetically deflected and focused. The 9" MW-22-2 and the 12" MW-31-3 crt's are nearly identical in size and deflection angle to post war tubes.

[Electronic M]

Originally Posted by dieseljeep

You'd almost have to swear that Philco was slightly ahead of the game!
Magnetic focus and deflection, a slightly advanced CRT design, that could easily be converted to a newer 10BP4 type.
I realize that the RCA and others had magnetic deflection as well, but the old CRT's were harder to sub.

IIRC they also were experimenting with high definition too; something like 800-900 horizontal lines...Unless I'm confusing them for another maker (I know some maker in the US wanted more than 525 before the war).

[Captain Video]

WHAT A FIND!!!

Where I live we get excited when we find a 1957 Philco... what you found is kind of a "Holy Grail" of TV collecting... congratulations!!!

[dieseljeep]

Originally Posted by Electronic M

IIRC they also were experimenting with high definition too; something like 800-900 horizontal lines...Unless I'm confusing them for another maker (I know some maker in the US wanted more than 525 before the war).

Wasn't France using 819 lines at the time? Britain was using 405 lines until 1967???

[tubesrule]

The French 819 standard didn't start until after the war in 1949. The English 405 system ran through 1984. They started 625 PAL color broadcasts in 1967.

[Captain Video]

France used 819 lines at that time. A pity that their TV programming was really crappy in those days, it was a waste of their technology. They had only state television, and the programs on the air were very boring. That is one of the reasons why France had only 1 million TV sets in 1960.

[vts1134]

I took the front cover off of the tuner today to see what I could see. It's not much to go on, but does any one know who may have made this tuner? Is it a Philco?



Under the replacement tuner bezel you can see 5 residue spots on the wood cover arranged in a circle. Could these be the remains of 5 channel labels from the original tuner?



One other thing I noticed while looking up at the set from below was that in typical prototype fashion this set isn't quite "finished" 100% as you can see in the shots below. It almost makes me wonder if they re-used a radio cabinet and re-fashioned the center for TV use.