In for more basic problem but query here , should anyone know, as only a Polish reference out there. All seems original in there and o/p devices TO3 Motorola, badged SCSP1 and SCSN1. Presumably , as only +/-24V rails 3055/2955 would be adequate , if required, but if anyone knows for sure, for future reference.
Marshall Master Lead combo, 1978
Jun 21, 2010
4 Replies
This schematic shows MJ3001 and MJ2501 as equivalents for SCSN1 and SCSP1:
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These are Darlington pairs, so they have much greater hFE than the
2N3055/MJ2955. They're only about a fiver a pair from Farnell.
Adam Sampson
"Nutcase_Kook"
** The devices are DARLINGTONS - d*****ad.Did you not notice the total absence of DRIVER transistors - eh ???
The pair are MJ2501 and MJ3001.
.... Phil
The info is out there, for all, in ASCII format now
"Adam Sampson"
** If someone fits 2N3055s and MJ2955s instead of the correct types, the transistors will run hot but deliver low power.Seen done it a few times and the repair tech could not figure it out.
.... Phil
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