Just picked up a Sel-Son CRT substituter model CS-5. The instruction pamphlet is VERY skimpy. Is there a list of CRTs that the CS-5 can sub for? Surely this one CRT (with no number) can't sub for every CRT model out there.

I've found little information on the internet, just a rumor that the CRT is a 5AXP4. Is this true?

BTW, I'm still working on my experimental one-of-a-kind 1950's Delco car TV. The set has sound, sweep, HV and video now. I just want to try the Sel-Son before pluging in my one 8AP4.

Bob D.

This article shows my Tele-Chek substitute kit with a 5AXP4 CRT:

http://antiqueradio.org/5AXP4PictureTube.htm

As explained in the article, the 5AXP4 has a 53-degree deflection angle, making it suitable to sub for many early round CRTs. I don't know about your 8AP4 offhand, but if it has a similar deflection angle and it uses magnetic focus (and the same pinout), the 5AXP4 should sub.

Here's a website where you can look up the data sheet for your 8AP4:

http://tubedata.milbert.com/index.html

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

The 5AXP4 can sub for just about any common round B&W tube used from 46 -51, possible exceptions might be larger tubes that use more high voltage than it can handle, the 30BP4 comes to mind but I'm not sure what the HV limit is.

I even used one on an RCA Projection set that used a 5TP4 by disabling the high voltage tripler so it only had about 9000 volts.

You can use it for the smaller rectangular tubes also but the geometry may be funky.

It should sub your missing 8" tube very nicely.

Just picked up a Sel-Son CRT substituter model CS-5. The instruction pamphlet is VERY skimpy. Is there a list of CRTs that the CS-5 can sub for? Surely this one CRT (with no number) can't sub for every CRT model out there.

I've found little information on the internet, just a rumor that the CRT is a 5AXP4. Is this true?

BTW, I'm still working on my experimental one-of-a-kind 1950's Delco car TV. The set has sound, sweep, HV and video now. I just want to try the Sel-Son before pluging in my one 8AP4.

Bob D.

I removed the CRT from the Sel-Son case and it is indeed a 5AXP4. (The yoke was covering up the ID.) Son of a gun, the logo on the tube says "GM Delco" :scratch2:

Bob D.