In Reply to: RE: NYAL OTL3 posted by unlisted on March 21, 2014 at 06:03:06:
A bit more information.
I checked the grid 1 resistor to ensure the tube was properly biased and it tested fine, but replaced it anyway: No change, V3/5 still turn red.
Wanted to take other measurements to see if that would help me track down the issue. Lowered the plate current to ~220mA and found the B+/2 a bit off. Lower grid V, upper grid V, B+, and now B+/2 all per target and stable. Adjusting the plate current and/or balance fixed the red 6LU8, but the V3 6LF6 still turns red after a couple minutes. Tried a couple other tubes and same result. (Have an unused 6LF6 matched dozen from RAM Labs I bought a long time ago, but don't want to use until I'm certain they'll be okay.)
The 6LF6 V3 was hot enough to melt the top off the jumper top, so this doesn't look normal to me.
Any inputs?
Regards,
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: NYAL OTL3 - unlisted 11:39:25 03/21/14 (19)
- RE: NYAL OTL3 - rhinohifi714 17:35:04 03/21/14 (18)
- RE: NYAL OTL3 - unlisted 18:01:52 03/21/14 (17)
- RE: NYAL OTL3 - airheadair 11:51:57 03/23/14 (16)
- RE: NYAL OTL3 - unlisted 13:16:15 03/23/14 (15)
- RE: NYAL OTL3 - unlisted 14:35:23 03/24/14 (14)
- RE: NYAL OTL3 - rhinohifi714 18:37:03 03/24/14 (11)
- RE: NYAL OTL3 - unlisted 19:26:19 03/24/14 (10)
- RE: NYAL OTL3 - rhinohifi714 05:34:54 03/25/14 (9)
- RE: NYAL OTL3 - unlisted 16:00:21 03/25/14 (0)
- RE: NYAL OTL3 - unlisted 06:41:52 03/25/14 (7)
- RE: NYAL OTL3 - unlisted 09:05:27 03/25/14 (6)
- RE: NYAL OTL3 - rhinohifi714 16:00:41 03/25/14 (5)
- RE: NYAL OTL3 - unlisted 17:05:37 03/25/14 (4)
- RE: NYAL OTL3 - rhinohifi714 17:42:49 03/25/14 (3)
- RE: NYAL OTL3 - airheadair 23:22:30 03/25/14 (2)
- RE: NYAL OTL3 [SOLVED] - unlisted 12:46:16 03/26/14 (1)
- RE: NYAL OTL3 [SOLVED] - airheadair 14:23:39 03/27/14 (0)
- RE: NYAL OTL3 - rhinohifi714 18:20:42 03/24/14 (1)
- RE: NYAL OTL3 - unlisted 18:50:42 03/24/14 (0)