4X811

Finally got the tube sockets ordered for the new 811 amp.

Soon there will be a pair of 4-400s with sockets and blower available for more serious amplifier duty in someone else’s shack.

We will be using four 811s along with our 1500vdc one amp HV supply.

The linear will still be larger than it needs to be and rack mounted but it will also be a little better behaved without the noise from the blower to modulate the airwaves.

The conversion should be fairly easy. Just pull the tubes, sockets, blower, build a bias supply, add a low speed fan, and find a 16 amp 6.3vac filament transformer. Need to check that again but the last time I looked an 811 needed 4 amps at 6.3vac for the filament. Man!, that is 100 watts just to light the tubes!

No way am I going to buy that kind of iron new or used. Good thing I saved those 24vac 4 amp utility transformers. Looks like one of them is going to have its secondary rewound for 6.3vac. Shouldn’t be too hard. About six turns is all it will take.

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