My bad, it was listed somewhere as a cross reference but I should have looked a little closer.
How important is max voltage in this case, it looks like there should only be a few volts across it right ? All those you listed (although very welcome) are obsolete, I can't imagine there isn't a reference that would work and is still available at mouser.
How important is max voltage in this case, it looks like there should only be a few volts across it right ? All those you listed (although very welcome) are obsolete, I can't imagine there isn't a reference that would work and is still available at mouser.
Voltage drop is around 10-12 V according to the schematic. So any of them will do the job. Respect to the obsolescence, my apologies, but I live in a country that things appears 50 years later than in the "first world". google for any JFET with 25-30V capabilities and a current of, say, 20mA.
Oh yes I'm 100% certain, they actually blew to pieces, together with those way to closely rated BC546/556 (rated for 65V when there's actually 76V across them, it's quite strange they actually last this long in these amps, this fault is well known in these amps).
Is "drain source on resistance" important in this application, because the j112 has only 50ohm where the original have 650ohm ? Looks promising otherwise, thanks Mooly.
If you're absolutely sure they are the real deal (there are some fakes on ebay) that would be great.
On resistance isn't important because the FET is just being used as a basic current source. The omission of a source resistor means the current you get is totally device dependent and will vary from device to device depending upon the devices Idss value.
If it is zapped then I would do a full rebuild and also be sure to change those 2SD/2SB devices because those have a nasty habit of failing with an intermittently high resistance B-E junction.
If it is zapped then I would do a full rebuild and also be sure to change those 2SD/2SB devices because those have a nasty habit of failing with an intermittently high resistance B-E junction.
and its also working directly into a 47uF cap which resists suddenly having the output voltage across it change.Makes a lot of sense indeed. I'll post an update when I installed all the new parts.
A previous repair (by a professional according to the invoice) clearly made things worse, I suspect some parts were changed, because some stuff definitely wasn't original and the soldering was awful, and turned on again without any current limiting.
A previous repair (by a professional according to the invoice) clearly made things worse, I suspect some parts were changed, because some stuff definitely wasn't original and the soldering was awful, and turned on again without any current limiting.
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