RCA 21CT55 #8802897 is Dead

[cbenham]

Originally Posted by Tomcomm

Newvista...........Here's a tube version of the RCA external input driver for the Roundies I got from Pete D. Hope you can use it..........Tom

Thanks for this link and also for the Broadcast news links posted by Phil Nelson a few messages later.

I've built a few video adaptors for various color sets but all mine have been using basic transistors.

While they work well, they are certainly not as elegant as one using an IC.

Would you share your IC adaptor schematic with the list?
Regards,
Cliff

[Tomcomm]

I use a Signetics NE5539 video op amp. It drives the 1st video amp grid with at least 3vpp and also the video monitors I use for all PQ comparisons.

[wa2ise]

You should replace those wax caps!

[cbenham]

Originally Posted by Tomcomm

I use a Signetics NE5539 video op amp. It drives the 1st video amp grid with at least 3vpp and also the video monitors I use for all PQ comparisons.

Thanks very much for the NE 5539 information and schematic. There are instances where as much as 8 volts pp are needed for some sets and also opposite polarity video at that same level, so I'll be breadboarding this to see how far I can push it.
Regards,
Cliff