Testing a 21EAP4 Predicta CRT

[DaveWM]

under the motto of "1st do no harm" I would try it on another working set and see how it looks. I know that some CRTs may have odd pin outs (found this out about predicta CRTS a while ago), so you could triple check how the socket is wired to confirm you UA settings. I have also had decent performance even with dead reading CRT's not great but decent. Lastly are you sure its a 2.3 and not a rebuilt with a hotter filament? again a quick power up of the set with a VOM on the filament will confirm what voltage its been getting. so to sum up,

confirm pins by checking to see how the socket is wired

check filament voltage

try in a working set if available.