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Old 04-06-2009, 04:56 PM
Gwil Gwil is offline
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Join Date: Apr 2009
Posts: 1
Default Transistor Trauma

OK so I'm finally nearly done, but there's a couple of things regarding transistors that give me pause for thought before I try turning it on (I'm sure these should be pretty obvious, but I'm a rookie, so go easy here!)

So firstly I noticed that the transistors in Q4 and Q5 are TN2907, but from the photo Grant's put in the manual it looks like the E leg on his transistor doesn't match up with what it says on the PCB - I've assumed the silkscreen has been labelled wrong and orientated the transistors like in the photo and how it also suggests in the vintage manual, is that right!?

Secondly, the TN2907 transistor for the RS232 wiring is making me ponder too for a similar reason - the vintage manual suggests the E-leg is the topmost pad on the PCB as you look at it (D/C board nearest you), whereas the identification chart on page 11 and Grant's photo's makes me wonder if it's not actually supposed to be the bottom one!? So where should the E lead actually go, top or bottom!?

Hope that all makes sense anyways - any help gratefully appreciated!
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