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Hi guys I've been given from a friend that has an old store a bunch of OPT's
all about 5 watt, they are 2k, 2.5k, 5k and 7k at 8 Ohm plus 20 NOS PCL82's.
I thought that I could build some small 3 watt amps for the kids to play with,
the only thing I need are some power transformers and a few odds and ends.
I've been looking on the net for some schematics and I found this one, the OPT's are
5k so I'm OK there, but I am a little unclear about the power transformer.
Each PCL is about 45mA so 100mA is OK fir two tubes but what would the voltage be? he shows
90-170v, does that mean anything from 90 to 170v?
Thanks Guys.

90-170 volts is very small. The xCL82 requires about 220-230 volts on the secondary winding. Also this tube have more power in pentode mode, but have great sound in triode mode

Translation that was with the schematic:

This simple tube amplifier uses ECL (parallel) or PCL (serial) tubes, a combination of triodes and end pentodes. Tubes such as PCL82, PCL84, PCL85, PCL86, ECL82, ECL84 and ECL86 can be used. I used a PCL82 tube with 16V ohm 0.3A and an anode loss of max. 7W. The amplifier is powered by a grid-shaped transformer with a glow voltage selected according to the tubes (for me 16V 0.6A). The anode voltage of the tubes is not critical, it can be about 100 - 200V according to the required power. Higher voltages will allow for greater power, but the tubes will be loaded with greater anode loss and current, which will cause faster wear. Filtration with two 100uF capacitors separated by resistors is necessary for better removal of the abdomen. The 22uF capacitor is an additional voltage filter for the pre-amplification stage that is the most sensitive to ripple. The speakers are connected via the output port. At the input is a stereo (double) logarithmic potentiometer for volume control.

Attention! There is a dangerous voltage in the amplifier! Before handling, always disconnect it from the mains and make sure the capacitors are discharged.

*** not sure why you'd remove the abdomen ???

... tom

Thanks guys for the help.

Regards
Greg

Me again, I've been playing around with PSU Designer and I think I have the PSU done
could you tell me if it's OK. Using a Hammond 363AX and a 156R with a 5Y3GT rectifier.
The specs on the 5Y3 filament states 2A and the 363AX is 2A will that be OK?
Typical characteristics for pentode class A is 170V.

Regards
Greg

I'd feel better with a 33uf for C1. If you need a slight bit more voltage and a slower turn on, you can use a 5Z4. Russians got em cheap.

Thanks for the reply, I'll try that.

Regards
Greg