100 Mono Block developed a large hum

[postman56]

Just received my two 100 Mono blocks back from getting a new set of Hayseed Recaps kit installed and new rectifier tubes.
All was sounding great until one developed a buzz and it appears one 6L6 was glowing.
I'm not a tech, and mine lives quite a ways away, so if any one can suggest what i should look at before sending off,I'd appreciate hearing from you.
Much Appreciated.

 

[dcgillespie]

The Hayseed caps took care of recapping the power supply, but were the caps throughout the audio circuits replaced as well? If not, they certainly need to be in these models.

One quick test you can do is to swap the two 6L6 tubes in the unit having problems. If the glowing 6L6 moves with the tube so that now the tube in the other socket is glowing, then the problem is likely the tube itself. On the other hand, if the tube in the same socket always glows regardless of what tube is installed, then it indicates problems in the unit itself. Also note that these units require the use of a tightly matched pair of output tubes. If they are not well matched, then one tube can be a current hog, and glow as a result, where as the other won't. Knowing if when swapping the tubes that the glowing tube moves with the swap, or stays in the same socket is the first order of troubleshooting for you at this point.

I hope this helps!

Dave