In Reply to: New Tubes (6CA7)--now bias too high posted by daveap on February 8, 2016 at 17:15:07:
You should be able to bias those without any difficulties.Does the bias reading come down after the several seconds have passed?
Bias reading problems could have different causes. The first thing I think of is cleaning and retensioning socket contact #5 for the four power tubes. I suggest 99% isopropyl, interdental brush of suitable size, and compressed air to promptly blow the alcohol out of the contact after scrubbing. To retension the socket contacts, press on the top and bottom of the "C," not directly opposite the split in the "C." If you have a look at the contact, I think you'll see what I am referring to (assuming you have the original sockets).
Of course, this might not be the cause, but bias problems are often enough caused by contact issues with #5.
Edits: 02/09/16 02/09/16 02/09/16 02/09/16 02/10/16
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Follow Ups
- RE: New Tubes (6CA7)--now bias too high - petercapo 15:49:23 02/09/16 (8)
- RE: New Tubes (6CA7)--now bias too high - daveap 17:04:47 02/10/16 (7)
- RE: New Tubes (6CA7)--now bias too high - petercapo 17:19:10 02/10/16 (6)
- RE: New Tubes (6CA7)--now bias too high - daveap 13:19:56 02/11/16 (5)
- RE: New Tubes (6CA7)--now bias too high - petercapo 14:15:10 02/11/16 (4)
- RE: New Tubes (6CA7)--now bias too high - xaudiomanx 17:49:02 02/15/16 (3)
- RE: New Tubes (6CA7)--now bias too high - daveap 15:04:04 02/16/16 (2)
- RE: New Tubes (6CA7)--now bias too high - xaudiomanx 17:32:24 02/16/16 (1)
- RE: New Tubes (6CA7)--now bias too high - jsblock 04:56:04 05/05/16 (0)