[AMPS] Grid Current Indication-SB220

measures 2@vc.net
Sun, 22 Oct 2000 15:02:54 -0700


>I have just acquired an SB220 that had a parasitic oscillation. I have 
>repaired the burnt components and nothing is smoking now. I get a negative 
>reading when switching to the "grid" setting on the meter. (Enough to pin 
>the meter to the negative side). This occurs with no tubes installed, so 
>problems in the grid circuit seem unlikely. 
>Any hints as to what to look for? 
>
The 0.82-ohm resistor may be open.  Do you have 3A glitch diodes across 
the meters?  Have you disconnected the 110v power supply from the bias 
contacts on the relay?  Have you read the article about the SB-220 on my 
Web site?

cheers,  Rich

-  Rich..., 805.386.3734, www.vcnet.com/measures.  
end


--
FAQ on WWW:               http://www.contesting.com/FAQ/amps
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com