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SR-52A rebuild project (SR-52A 942058 LTA4176)
03-05-2021, 03:33 PM
Post: #4
jebem Offline
Senior Member
 		Posts: 1,355
Joined: Feb 2014
RE: SR-52 rebuild project
Q4 is used with Q3 as a Darlington pair to drive the motor on the original SR-52 model PCB.
Q1 and Q2 are used as the Darlington pair to drive the motor on the SR-52A revisions.

Q4 do not have special requirements in this position, any npn high current type is adequate, see the Q2 specs on the SR-52A revision, it should be similar.
I would say a npn with IC of 1 ampere maximum and VCE of 20 volt would do the job.
Jose Mesquita
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Messages In This Thread
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 02:14 PM
RE: SR-52 rebuild project - jebem - 03-05-2021 03:33 PM
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 03:39 PM
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 04:50 PM
RE: SR-52 rebuild project - jebem - 03-05-2021, 05:16 PM
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 06:28 PM
RE: SR-52 rebuild project - jebem - 03-05-2021, 08:26 PM
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 09:53 PM
RE: SR-52 rebuild project - albertofenini - 03-05-2021, 09:12 PM
RE: SR-52 rebuild project - albertofenini - 03-06-2021, 03:59 PM



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