How about these sockets/chimneys for 4X250s?

[Opcom]

This is the modulator tube subchassis from the T-195/GRC transmitter. Two 4X150D tubes fit, also certainly the 4CX250s will also fit having the same size anodes and same base/pins.

I want to consider this for a linear RF power amp. The only issue I can see is that the chimneys are a type of brown composite, plastic or 'bakelite?' material.

They seem to have fared well, not burned or carbon-track arced in any places, though a little darker here and there, more near the tops of the tube anode area. Hopefully there will be more airflow than stock if they are used so the tubes and chimneys should be much cooler.

It ran on 1KV in the T-195, but I'd prefer 2KV naturally! The wiring and two caps there specifically for audio as a modulator can be removed, and screen bypass caps added underneath.

I see no reason not to go ahead, but does anyone have objection to this assembly on 160-10M HF?

Thanks in advance,

Patrick

[WD8BIL]

Should be just fine. I ran 250Bs in a 2 meter amp with 1850VDC for years with one of those setups. Nolo problemo!

[Opcom]

Thanks!

[K9PNP]

I have worked on the T-195 when they were still in the mil system.  Have seen them looking worse than this and still worked.  Apparently the 'darker brown' is due to heat; at least that is what we blamed it on.  That was a good xmtr.  You just didn't want to have to pick it up and move it around a lot.

[KD6VXI]

Pat,

I couldn't tell you how many amps I built around that socket.  RF Parts had that socket for 29 bucks for awhile.  I bought 40 or more of them....  Next time I tried to buy them the price had skyrocketed.

I have one set left.  So I guess I built a few of them.  Pete Dahl used to have a 2 x 250b xformer off the shelf.  It was advertised as a Mudshack 250B.  It would supply enough current to push a pair of 8930s, loafed with a pair of 250B tubes

I liked the BC series.

--Shane
KD6VXI

[Opcom]

They are very economical at Fair Radio right now.