[WallaceRoger]

I bought a Conar 223 for a decent price. I need to replace the bulb that displays if there's a short, but otherwise it looks like it just sat in an attic for years.

I wanted something simple to start with, that doesn't have a complex calibration procedure. The only calibration to do on this is replace caps and resistors when they go out of spec. I'll check and replace those as needed next week.

Setup is pretty simple following the data sheets. I tested a couple of 71A tubes yesterday just for kicks, both were in the "good" range (can't check for shorts since the bulb is broken, will buy a new one soon). However, I'm not exactly sure is I'm testing my 27 tube correctly... it has 5 pins and after rotating it enough I was able to line it up and insert using the same socket as the 4-pin 71As. When I followed the test procedure the needle went all the way left, which tells me either my 27 is bad or I did the test wrong.

My question is, does anyone else have a Conar 223 and if so, am I using the right socket for the 5-pin 27 tube?

Also, I'm guessing the wire lead with the clip on top is for testing my #24 tubes?

[Radioroslyn]

Looks like your lamp is a NE-51, use to be a common one back years ago. Don't have a 223 but it's typical for the tester to have a 2 sided cap (grid) one side will fit the older larger caps like a 24A or 75 tube and the other would fit the cap one the newer self centering tubes like a 6A8 or 6K7. After taking a quick look at the manual it doesn't appear to have a 5pin or 6pin socket. Must have an adapter to fit these tubes. Conar was out of Wash Dc making kits in the late '60s/70s. By this time 5 an 6 pin tubes are considered obsolete.
Manual is here   http://bama.edebris.com/manuals/conar/223

[WallaceRoger]

Thanks for that manual, I found and downloaded all of the data sheets but hadn't found that yet. The Combination Socket is the one I was using, that one does test 4-pin tubes and allegedly will do 5-pin. Sounds like I need to do a bit more research here and see if I need an adapter.

[WallaceRoger]

Ok, I confirmed it will do 4, 5, 6 and 7 pin large, octal, loctal, 7, 9 and 10 miniature, and 5 pin nuvistor, novar and compactron. The manual lists these in the features. I guess I was doing it right the first time.

My next step is to test the caps and resistors, replace as necessary, get that bulb and clean everything up. Then retest. If my 27 tube is no good that would explain why my Model 20 didn't work.

I also found a guy who added a cap inline before the meter to help protect it, I think I'll do that too.