Asking for PLH complete project

[Jay]

I have quick read the pdf and googled and read some threads to get the initial idea about this baby, but still have no idea about how I can build this PLH.

The FET, can I use one of K135 (or the J50 I don't remember).
The FET, can I use IRFP250?
The JFET, I will find from old PCBs but what should be the rating?
How big is the heatsink for FET?
How big is the heatsink for R? (I think I'll use light bulb!)
Is it 10W? How about the total consumption?

Please point me to pictures if available 😀

 

[Nelson Pass]

1) You can use any N channel power Mosfet you like

2) Yes

3) There is no Jfet in the design as published

4) Big. You want a sink which will rise about 25 deg C with
an 80-100 watt dissipation per channel

5) Light bulb requires no sink, but consumes about 20 watts
each

 

[Jay]

Thank you Mr. Pass.

I rechecked the pdf and I saw Q1 (JFET) and Q2, so I still don't get it... 😕 May be I need to read more threads

Light bulb consumns about 20W. I took it that resistors consumn much less than that.

 

[Nelson Pass]

I think you are looking at the wrong project. The PLH
is identified by that title, and the one with the power JFET
is Zen Variations #8 (ZV8).

😎

 

[Jay]

Oh, thank you. That's my mistake

I will build a PLH tonight. With a 28V rail 😎