Ashdown ABM300: transistor touches heatsink = buzz

[lildrgn]

Playing around the other day, heard a buzz, figured there was a loose screw or something. Turns out it's a transistor touching the heatsink. Not a lot of wiggle room on either one, any suggestions to make it stop? I think at loud volumes, it can't be heard (hadn't noticed it until noodling around by myself), but probably isn't good for that transistor.

Thoughts??

 

[agedhorse]

Normally if this were to occur (designers try to avoid this in the first place), a designer would specify that a small amount of electronics grade silicone adhesive or potting compound be placed between the two parts during assembly. What you may be able to do is slip a small piece of very thin self adhesive electronics grade felt/foam/rubber sheet between the two with the adhesive side to the cap (not transistor). The material is less than 1/16" thick.

 

[lildrgn]

thanks man!!

 

[agedhorse]

Doesn’t take much either.