WS1 SS Rectifier (w/Thermistor) blowing fuse upon immediate start up....

I was with my tech today who finished repairing the issues with my M125 amp - I also had him install the Rubli delay board.

Amp was working just fine with the WZ68 and two output tubes - I told him I'd be running with the WS1 - so we plugged that in - turned the amp on and immediately - whap - fuse blown.

He then replaced the fuse and controlled the incoming voltage to prevent a blown fuse and each time - whap (it would have blown a fuse)- we even tried the other WS1/T - same issue. Went back to the WZ68 and all is fine.

I'm home with the amp - and I've tried the old Mullard GZ37 - works just fine - and I'm using my bucking transformer - so my voltage is around 116v.

I'm only running two output tubes and the bias at .500 v. The delay of close to 30 seconds - hadn't even kicked in - it went straight to blown fuse. I also have the yellow sheet mod.

I've sent an email to Weber - I'm just surprised the WZ68 is absolutely fine - and this thing just doesn't work - I assume is it incorrectly built.

Thanks,

Very likely that it is incorrectly built. If you can, check it with an ohm meter and compare to your WZ68.

Inside there are two diodes and possibly a thermistor. It’s easy enough to pop the top. With the delay (thermistor) it’s tight in there and a lead might be touching the copper. Pretty sure diodes mostly fail closed, so that would the short. Either way ohm it out and you will know. You can replace the diodes in the ws1.

Thanks you two - yes - I'm getting ohm readings from pin 8 to 4 and 8 to 6. The internals are covered in black goop - like a klon guitar pedal. I'm not sure what it is supposed to be but the WZ68 doesn't seem to be that way.

I'm going to send back for a refund.

UPDATE:   Refunded by Weber - very nice folks.  Weber tested them and confirmed they are fine - they just will not work with the amp using two output tubes - or perhaps my amp in particular that has the yellow sheet mod and the Rubli Delay board - which I'm sure has anything to do with it since the amp works with all other rectifiers.  I'll stick with glass or WZ68s (Weber SS).

rebellovw wrote:UPDATE:   Refunded by Weber - very nice folks.  Weber tested them and confirmed they are fine - they just will not work with the amp using two output tubes - or perhaps my amp in particular that has the yellow sheet mod and the Rubli Delay board - which I'm sure has anything to do with it since the amp works with all other rectifiers.  I'll stick with glass or WZ68s (Weber SS).

Thanks for the update. I still think there was something amiss with that rectifier. Especially since all other rectifiers you tried worked just fine.