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Need help by Aikido All in one 9 Pin

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I have buy for a lot of year a 9 Pin Aikido all in one PCB
and like to build it at the moment.
I like to use the 6N23P witch are the russian 6dj8 Tubes for all Postions and My Transformer do have measured:
247V AC 70ma
6,8C AC 2,5A
The value of capacitors ist clear , for the regulator i like to take the LM317T
Can i use alternativ for all MUR410G the 1N5402(D9, 10, 11, 12 ) ? Or ist it only as replace for the D5 -D8?
Now my big problem the Resistors;
I think this values are clear
R19 499 ohm
R20 124 Ohm
R1 1 M
R11 1M
R9 100k
R10 90K ( ? )
and the rest, i need realy help!

Can anyone help me please with the other resistor Values?
I like to use the recommended values B+ Voltage 200V for 6dj8



Thank you very much and regards from germany
 
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Kompakt,

If 247 volts AC is connected to the PS board you will likely have over 300 volts raw DC at C7. So C7 will need to be rated at 350 to 400 volts to be safe. You will need some large resistance (and probably 5 watt-rated) resistors for R12 in the power supply to drop down to your 200 volts desired. I wouldn't run the 6DJ8s at over 200 volts, just my preference.

I've built an all 6DJ8 Aikido (runs on about 170 volts DC). I forget what resistors I used for R 3,4,6,7 but I can look it up if you like. Give us a list of only the resistors you DO NOT know.

6.8 VAC could be tight for getting 6 volts DC regulated. You should really be starting with about 8 VAC. Your best chance of getting the regulated voltage you need is to say with the MUR410s and the LD1085 as they have less drop.

Steve
 
Hello Steve!
Thank you very much!
Ok if i build the PCB with the MUR410 and the LD1085, can i stay with my 6,8V transformer for 6,3V heater Voltage?
Can you reccomend me a Voltage setup(over 200) that work fine with my transformer?
This are the unknown resistors : 3 4 12 14 15 18
Thanls a lot!
Best regard

Best Regards
 
Kompakt,
My Aikido is running 160 VDC on the "top" anodes.
R1=1M, R2=300, R3,4=300, R5= 300, R6,7= 180, R8=300, R9=100K 1%, R10=87.5K 1%, R11= 1M, R17= 300K 1W, R18= 100K 1W

With 160 volts and R3,4= 300 ohms on the input tubes there is about 5.5mA through each tube.
With 160 volts and R6,7= 300 ohms on the output tubes there is about 8mA through each tube.
In both cases it's not too high to stress the tubes but high enough so they "warm up" and sound good.

R12 will depend on what the raw DC is across C7 and the voltage you want on the tubes. You might just have to buy a bunch of resistors of different values and try them out. Maybe start at about 12K and work your way down. You will probably need 5 watt wire resistors. Wirewound resistors are OK here, a little inductance won't be bad and wirewound won't be very expensive.

When it comes to your transformer the filament current is a bit marginal for a DC supply but you might get away with it. Lower the regulator output to 6 volts by changing R19 to 470 ohm 1%. A LD1085 is a low drop out regulator but you still need a minimum of 1 volt more input than output so it will regulate properly.

S.
 
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