Q5 between EB 8R8 don't change the value when turning the R11 trimmer.
Q4 between EB don't measure nothing.
Q4 between EB don't measure nothing.
Problem. Either wrongly facing Q5 and Q4 (difficult to discriminate front or back because of the shiny fully plastic case), or damaged Q5, or trimmer, or Q4. When excluding wrong connections possibility in matrix board prototyping.
That's the JFET pushing some mA, but the cascode BJTs must cooperate too to have normal Vout changing result.
When I tested the FET I forgot to solder the source so the wrong readings.
It seems that now works but I have to power off because 1K ballast resistor starts to smoke because is 8W rated.
It seems that now works but I have to power off because 1K ballast resistor starts to smoke because is 8W rated.
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I don't have 1K5, I have two 2K7 in parallel 1K35, two 850R in series 1K7, I have other 1K so I can make 2K in series?
Two 2K7 strong power resistors in parallel sounds good. 340-280=60V/1.35K=44mA. Don't push the Vout down low much than target and staying long, the more the burn on the ballast.
![WP_20141224_002[1].jpg](/community/data/attachments/429/429425-b5ee4523c821344c2bf21822bbdc3d6c.jpg?hash=te5FI8ghNE)
Q5 EB 0R5 turning the R11 trimmer don't change ohm measurement, I guess Q5 is gone, Atlas DCA55 says short circuit emiter base.
Q4 EB 72K4
Q4 EB 72K4
Maybe they had problem from the start test. Make sure about face front and pins to be right with ones that Atlas says good.
Onlu measures wrong when is soldered to the rest of circuit, when I desoldered the 3 pins Atlas says PNP OK.