Tech-Master NIB TV Kit #5516

[Crist Rigott]

I did a little checking on other TV schematics from my Beitman's disc. I checked in the 1955 issue which is the same year the 5516 drawings were signed off.

As with most schematics from the manufacturers of the same time period, most were very similar. The Emerson chassis 120245D is very similar to the 5516 and it can use a 17LP4 or a 21YP4 CRT. It uses 14.5Kv with the same B+ and other voltages.

All-in-all, I looked at 6 different schematics (all string filament) and they went from 13.5Kv to 15.5Kv with similar tubes and B+ voltages.

Now, this is just me thinking, that if I were selling TV training and making kits to support that training, and TV's were getting larger screens then I would design a set that would support the trends. The chassis is certainly large enough for a 20MP4 and will fit with no problems at all. The design uses 3 IF stages and uses basically the same amount of tubes as most consumer TV's of the time. It's not like they scrimped like on my AMC 116T or a Muntz etc.

So I'm thinking that it will handle the 20MP4 without problems. I'm sure we all agree that the 17LP4B will work hands down. Anyway, it will last a lot longer than me. I don't plan on watching B&W TV 8 hours a day. Though, it is nice to see some of the TV shows when I was a kid!

[Kevin Kuehn]

You'll likely be fine with either CRT. Of course you could hold off on the CRT purchase until after you have the set operating with an 8XP4 test CRT, at which point you'll have a better idea of the sets supply capabilities. I'm surprised if your manual or schematic doesn't specify the B+ and anode voltages. But as you suggest the circuits of that time period would have been very common.

[Crist Rigott]

Originally Posted by Kevin Kuehn

You'll likely be fine with either CRT. Of course you could hold off on the CRT purchase until after you have the set operating with an 8XP4 test CRT, at which point you'll have a better idea of the sets supply capabilities. I'm surprised if your manual or schematic doesn't specify the B+ and anode voltages. But as you suggest the circuits of that time period would have been very common.

The schematic shows +130V and +260V but no HV value.