Tech-Master NIB TV Kit #5516

[Crist Rigott]

Some pictures.

[Crist Rigott]

Kevin,
Thanks for the reply. I needed that info for a CRT! Where did you get it? Was it a page from an Allied Catalog or such?

[Crist Rigott]

I also think it uses a magnetic focused CRT. There is a fly-back transformer and the schematic shows a HV lead going to a 2nd anode on the CRT.

I think the ad has a typo.

[Kevin Kuehn]

The listing is from my 1956 Burstein Applebee Co. Radio Master catalog.

Magnetically deflected, but electrostatic focus, unless your kit came with a electromagnetic focus coil? Your build manual must share some information on compatible picture tubes?

[Crist Rigott]

Originally Posted by Kevin Kuehn

The listing is from my 1956 Burstein Applebee Co. Radio Master catalog.

Magnetically deflected, but electrostatic focus, unless your kit came with a electromagnetic focus coil? Your build manual must share some information on compatible picture tubes?

OK, I'm confused. There doesn't appear to be a focus coil used in this TV.

Here is the schematic:

[Crist Rigott]

The manual suggests "A low-voltage electrostatic or self-focus picture tube is recommended for use with this receiver."

[Kevin Kuehn]

Originally Posted by Crist Rigott

OK, I'm confused. There doesn't appear to be a focus coil used in this TV.

That's because it's intended to use an electrostatic focused CRT. Which is nothing more than a DC voltage that connects to the CRT's focus pin. I think on a 17HP4 it's G4, but I can't make it out on your schematic.

https://frank.pocnet.net/sheets/127/1/17HP4.pdf

[Crist Rigott]

Originally Posted by Kevin Kuehn

That's because it's intended to use an electrostatic focused CRT. Which is nothing more than a DC voltage that connects to the CRT's focus pin. I think on a 17HP4 it's G4, but I can't make it out on your schematic.

https://frank.pocnet.net/sheets/127/1/17HP4.pdf

On the schematic, pin 6 is grounded.