Tubelab se with 300b checks out fine. Plate current adjusted to 75 ma. Source connected. Sounds fine for about 2 minutes and then plate current disappears as does sound. After powering down for a few minutes and then turning on, the same thing happens. When powering up with source connected, left channel takes longer to warm up than right channel. Don't know if that's related to the plate current problem. Does anybody have any suggestions for troubleshooting? Thanks.
Hi and thanks for the reply. I'm not sure what you mean by Sand, and are you referring to U1 and D1 as far as overheating?
Sand is composed of silicon dioxide from which the silicon is extracted to make solid state devices, hence the term "sand".
I'm kinda having similar problem. Have you solved your issue?
My problem,
Left channels grid current is pretty much different than the right ones.
I have checked the trimmer resistors and I made sure that they are all the way down.
What could be the cause of that? I am suspecting mosfet but you guys might have a better idea to check.
By the way I have tried different tubes to check tube was faulty or not. Tubes are OK
My problem,
Left channels grid current is pretty much different than the right ones.
I have checked the trimmer resistors and I made sure that they are all the way down.
What could be the cause of that? I am suspecting mosfet but you guys might have a better idea to check.
By the way I have tried different tubes to check tube was faulty or not. Tubes are OK
Why would you want it that high? You may want to try 68 - 70 mA.Plate current adjusted to 75 ma.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
- Home
- More Vendors...
- Tubelab
- tubelab se 300b plate current