I noticed some differences in transistors of my ADSRs, too. Okay, here
we go (components marked on the PCB in brackets)

A-140 with the flat LED: Q1 to Q4 and Q6: 547 (549); Q5: 557 (559)
A-140 with round LED: Q1and Q2: 549 (549); Q3, Q4 and Q6: 548 (549);
Q5: 557 (559)

Paul (confused)



Tim Stinchcombe wrote:

> The difference in transistor types is interesting though, and may
> account for some diference in performance - I'd be interested to know
> the difference if you can be bothered to check. On mine, Q1-4 & Q6
> are all BC547C (board marked BC549), and Q5 is a BC559C, same as
> board says.
>
> Tim