[TenTec] 425 Failure

[Art Trampler]

Hi Gang,

 

A few months back I put 100 watts into my Titan 425 and the rest is history.
In getting ready to put new tubes in it I am going through it, and the wire
feeding HV from the RF Choke to the anodes broke/was blown apart in the
incident. There was some discoloration of the sheet metal under it, and it
was kind of stuck to the metal. I didn't know it was broken inside the
insulation until I manipulated it. There is also some of the lacquer coating
(whatever it is) blown off the RF choke and on the sheet metal.

 

The RF Choke is, I believe, the original style with all the turns together
(no spaces between sections of turns). I have read that later Titans had a
redesigned RF choke.

 

First, is the RF choke from RF parts suitable, or should I go to Ten-Tec?

 

Second, what wire do I want to use to replace the broken wire from the choke
to the anodes?

 

Third, anything else I should be on the lookout for and checking?

 

At least this may explain why, if I have shorted tubes, the amp powered up
with appropriate HV until I keyed it with about five watts, and then the two
main fuses immediately blew. I imagine the HV arced across the broken wire
at that point.

 

As always your thoughts are appreciated. I am less fond of not having a knob
and simple straight key when tuning an amp (Pegasus) than I once was.

 

73,

Art, K0RO