Randall pro tube 1000

[roadking]

Hey all amp people working on a Randall pro-tube 1000 was noticing between pin three and eight on the 6l6 power tubes there is what appears to be a diode but has a marking on it that reads HV50UF one is fried and the other readable.Checked both with diode test and capacitor test shows open but the case looks like a diode black with a silver band on end was wondering if any body else has had this.I remember the fender ultra linear amps i believe they used small caps in this position for parasitic isolation problems any help would be appreciated.

Thanks
Charlie
   

[sluckey]

It's a protection diode. They're typically rated for 3000v @ 1A.

[roadking]

Hey sluckey thanks alot makes sense now appreciate the help.

Thanks
Charlie