I have a tube tester that is labeled:
Series 920 Electronic Tube and Set Tester.
Made by the Precision apparatus Company Elmhurst LI NY.
The case is labeled:
Precision
Pattern no. 920
Serial no 12253
Model OAL M4349
Vacuum testing equipment
1CPF-60057 Portable vacuum Tube Tester
Navy Department Bureau of ships
By Precision Apparatus Co...
Contractor General Electric
Contract NXss-29461
Would you have any information on this unit or could maybe point me in the direction of someone who would or where to start looking. I would like the operations manual and any information on updating the tube chart.
Thanks
JB
B9233@aol.com

What you need is "Technical Manual TM11-1209", 20 November 1944. For Test Set I-157-A. PB 21976-BSIR 2(1):31; 07/05/46. I contacted the local liberary and asked for an inter-liberary loan for this manual and recieved it in about 3 weeks. In fact, I just finished copying it and returned it to the liberary today. This manual will provide full instructions and servicing information, as well as a full listing of parts and schematic. I have one of these tube checkers and am in the process of resoring it. It works very well. I also have a complete original manual and suplimental tube charts. Let me know if I can be of help.
Richard E.

:What you need is "Technical Manual TM11-1209", 20 November 1944. For Test Set I-157-A. PB 21976-BSIR 2(1):31; 07/05/46. I contacted the local liberary and asked for an inter-liberary loan for this manual and recieved it in about 3 weeks. In fact, I just finished copying it and returned it to the liberary today. This manual will provide full instructions and servicing information, as well as a full listing of parts and schematic. I have one of these tube checkers and am in the process of resoring it. It works very well. I also have a complete original manual and suplimental tube charts. Let me know if I can be of help.
:Richard E.

Is there any way I can get a full copy of this manuel,I need to repair this tester,
sincerely,
John