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Old 7th March 2008, 15:42   #107 (permalink)
gray52
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im fed up with waiting for tr2 so ive gone for bc 639 (maplin code vro6g) and ive looked at the data sheet and is the same for bc635. one thing ive noticed is that the legs (bce) are a different configuration to bc547 (tr1). this could catch you out as both the tr1 and tr2 look the same so you would follow the diagram and fit them the same way. but the bce are on different legs as follows:-

bc547 tr1 1) emitter 2) base (centre leg) 3) collector
bc639 tr2 1) base 2)collector (centre leg) 3) emitter

ive fitted this tr2 as per the diagram and it is now turned a quarter compared to tr1, can someone confirm this is correct? ive pm hgt but have not heard back from him.
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