|
Vintage Asylum Classic gear from yesteryear; vintage audio standing the test of time. |
|
|
|
Vintage Asylum Classic gear from yesteryear; vintage audio standing the test of time. |
|
In Reply to: Scott 299B Output tubes glowing Red posted by onekid on May 6, 2016 at 08:43:48:
It could be that you need to adjust the DC balance pot for each channel because one tube in each pair is working harder than the other to get that .99 VDC. That could make one tube glow red because it's drawing too much current while the other tube is just coasting.
The .99 VDC is the combined reading for both tubes and it doesn't tell what EACH tube is doing.
In looking at the schematic I don't know how Scott expected you to adjust the DC balance with one cathode resistor per pair of outputs.
Maybe try the hum test if you have high efficiency speakers or low impedance headphones to connect to the 16 ohm speaker terminals.
With the volume all the down down and no signal, listen for a hum in each channel and adjust the DC balance pot until the hum goes away on each channel. It works on my Scott 299A.
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Scott 299B Output tubes glowing Red - DaveV 16:32:28 05/06/16 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
