AnsweredAssumed Answered

8753A/phase lock lost/overload on input R

Question asked by marinho on Jun 12, 2008
Latest reply on Jun 12, 2008 by Dr_joel
Hello everybody,

I have been looking around the forum for the last days and did not find an answer to my problem, so here it goes.

We have a 8753A VNA here at school. Last week it was working fine and then turned off but itself without any reason or warning. I checked the electrical installation and it was ok. Then I figured that the problem was the fuse. It was was blown. 
I changed it and it started to work again. In the next day it has been working for 4 hours without any problem. Two days ago, while I was waiting it to warm up, the fuse has been blown again.

I already took a look at the service manual, but did not find any hint on how to identify or solve the problem. Can anybody give me a help?

Best regards,