Westinghouse H-223 restoration

[Pio1980]

Originally Posted by bandersen

I was told Westinghosue and others didn't use a flyback to avoid paying royalties to RCA.

How could RCA claim a patent on prior art, their superheterodyne downconversion claim notwithstanding?

[bandersen]

Originally Posted by Pio1980

How could RCA claim a patent on prior art, their superheterodyne downconversion claim notwithstanding?

I don't know the details but RCA definitely had TV patents.
Look on the back of most TVs and you'll see a label stating "Licensed under US patents of RCA"

You just need to convince the patent office that your application is different enough from any prior work. Plus, RCA was known for being very aggressive and screwing over the little guy.

[nasadowsk]

Originally Posted by bandersen

I don't know the details but RCA definitely had TV patents.
Look on the back of most TVs and you'll see a label stating "Licensed under US patents of RCA"

Oddly, my CTC-4 also references patents from N.V Phillips. Be curious what that’s about…

You just need to convince the patent office that your application is different enough from any prior work. Plus, RCA was known for being very aggressive and screwing over the little guy.

RCA was known for screwing over everyone…

[dieseljeep]

Originally Posted by nasadowsk

Oddly, my CTC-4 also references patents from N.V Phillips. Be curious what that’s about…



RCA was known for screwing over everyone…

I read a pate

[DavGoodlin]

Originally Posted by bandersen

I was told Westinghosue and others didn't use a flyback to avoid paying royalties to RCA.

I'm working on a Sparton 4900, which uses a HV supply that is entirely separate from horizontal sweep also. 6SN7 connected as oscillator makes HV using a tubular coil, feeds a 1B3.

[DavGoodlin]

The Westinghouse Home Products division in Sunbury was over 70 miles from the nearest TV transmitter, on a flat spot at RR tracks and river north end of town.

WGAL-4 (later 8) was on a tall building in Lancaster. Philadelphia had three more channels but was over 100 miles, so maybe they tested the sets on top of the nearby hills.

That tuner is pretty interesting, I wonder if that distance alone affected their designs?

[dieseljeep]

Originally Posted by bandersen

I was told Westinghosue and others didn't use a flyback to avoid paying royalties to RCA.

That's gratitude for you!
Wasn't it a joint effort by GE and Westinghouse to form Radio Corporation of America!

[Pio1980]

Originally Posted by dieseljeep

That's gratitude for you!
Wasn't it a joint effort by GE and Westinghouse to form Radio Corporation of America!

American Marconi, General Electric, Westinghouse, and Wireless Specialty Apparatus Co. formed the Radio Corporation of America (RCA).

[bandersen]

So...many...caps... These are just some of the 0.1uF bumblebees. Still many to go.



Barely any signal is making it through the tuner, but I can feed a signal into the IF just fine.

[bandersen]

After fighting with the tuner and trying every channel, I finally got reception on channel #6.


Time to dig into the tuner.
WOW! What a trip. One of the coolest tuners I've ever seen
A beautiful piece of engineering!

The coils and caps are routed out of PCB type material. Similar to what you'd seen in modern RF electronics.






and here's the problem
There are score marks on the adjustments for channels 3 & 4 and the coils are damaged.
Likely a tool slipped while someone was trying to make adjustments.

I'll try to carefully push it back into place and glue down.

[Tom9589]

We had an old Hallicrafters that had a "similar" tuner. It was a turret design like a Standard Coil tuner except that the strips were actual printed circuit boards with the coils etched on the boards. Never had to clean this tuner. Must have done something right. It was about 50% larger than the Standard Coil tuner.

[dieseljeep]

Originally Posted by Tom9589

We had an old Hallicrafters that had a "similar" tuner. It was a turret design like a Standard Coil tuner except that the strips were actual printed circuit boards with the coils etched on the boards. Never had to clean this tuner. Must have done something right. It was about 50% larger than the Standard Coil tuner.

Way back in the early 50"s most smaller cities only had one channel, so the tuner didn't give trouble or need cleaning.

[bandersen]

I carefully pushed the mangled coil back into shape and glued it down.


Success! I can now receive on both channels 3 & 4.

[bandersen]

Working on replacing the two multi-section twist locs now.
Even though they used twist-locs, there are existing mounting holes with the standing hole spacing for phenolic insulation wafers.
Perfect opportunity to use adapt-a-caps.


Ooops, slightly melted the wire insulation in a few spots
One down, one to go.

BTW those two 12K resistors in parallel is how it was originally built and shown on the schematic. Two 12K, 1W in parallel
I'm thinking 5.6K or 6.8K wasn't close enough?

[old_tv_nut]

"BTW those two 12K resistors in parallel is how it was originally built and shown on the schematic. Two 12K, 1W in parallel
I'm thinking 5.6K or 6.8K wasn't close enough?"

Can you post the circuit? If the original resistors were 10% or 20% tolerance, there wouldn't be much advantage in using two for a nominal intermediate value. More likely they had 1 watt components available cheaper than small quantities of 2 watt - but that could depend on the particular circuit.