Dim CRT on an R2001D

This forum exists for the purposes for discussing service monitors (This includes but is not limited to Motorola, HP, Aeroflex, GD, etc). Additional topics allowed include test procedures, interpretation of test results, where to find information about specific tests, antenna VSWR, return loss testing, duplexer and filter alignment, etc.

Moderator: Queue Moderator

Post Reply
crash
Posts: 29
Joined: Sun Oct 19, 2014 11:21 am
What radios do you own?: R2001C

Dim CRT on an R2001D

Post by crash »

As with many others, I had a dim CRT on my R2001D.

I have read many articles about using a Sencore CR-70 to 'rejuvenate' the CRT, but I lacked the CR-70. And, after spending a couple hundred dollars for a used CR-70, I replaced all of the electrolytic capacitors, as I found a few to be bad. The unit still would not pass the 'field test', so I opened it back up and found R-211, the Cutoff Set pot open. I ordered a new pot, and once the pot was modified to fit the CR-70, the unit now passes the field test!

I performed the test of the CRT, but it did not have any emission reading, nor could I set the cutoff level. As I had read others had had the same situation, I tried the CRT rejuvenate and Auto Restore functions of the tester, but still I had no emission or cutoff reading on the meter. But, I put the CRT socket back on and hooked up the high voltage board, and tried it our.

After getting the CRT all hooked up and power applied, it worked great! I could not believe the difference in intensity! The scope display was originally dim , but OK, to begin with, however, the text was very difficult to see. Afterwards, it was like a new CRT, the scope and text were the same intensity, and I could increase it to very bright afterwards!

I have heard this may only be a temporary fix, but it is still less expensive than a new CRT, and the R2001D isn't going to be turned on 8 hours a day/5 days a week in my home shop, unless I get a large increase in communications repairs, so I am not worried about it!

I have seen some people are working on LED displays that will operate in X/Y/Z mode, and they should come in different sizes for old CRT equipment, if that does come out being true, and at a reasonable cost, these old CRT display devices may have a new life!
Jeff 'crash' Young N8CMQ
Post Reply

Return to “Test Equipment & RF Equipment Alignment”