• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

CCS for tubes/valves: PCBs

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The reference string is the resistor and two LEDs that determine the base (and hence emitter) voltages. You want those constant and known, so it's usually fed from some stable source of DC tapped elsewhere in the amp.
This is from post 44.should I get the reference voltage direct after the rectifier,I take it after a RC filter now,or can I remove the RC filter that I have before the CCS?
Can I use the CCS with MJE340 with a 6B4G?
How?:)
 
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Ryssen said:
This is from post 44. Should I get the reference voltage direct after the rectifier, I take it after a RC filter now, or can I remove the RC filter that I have before the CCS?

Can I use the CCS with MJE340 with a 6B4G?

Keep the RC filter. Although hum on the supply will be attenuated by the potential divider action of R1 and the LEDs, hum on the reference could find its way into the audio.

If you mean could you use the MJE340 variant in the cathode circuit of a 6B4G, then yes.
 
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burnedfingers said:
What is the cost of the boards plus shipping to the US?

1st boards are headed over the Pacific tomorrow :^)

The 1st batch will be $8/board (we are paying the tooling charge, which -- as long as the design doesn't change -- will mean that the cost for the next run could be quite a bit less -- and the order was "small"). This includes a $1 donation to diyAudio/board.

Post to the US (up to 10 boards) is $6 Air/$4.50 surface. All other contries but Canada $7.50 Air/$5.50 surface. Canada is more complex. I can also send a few boards by letter post, but it doesn't get insured so i'd rather not do it that way.

dave
 
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