transistor match help

[spuddo]

Hi ,I'm repairing a mini contour / keyboard pcb.
Q9 was snapped off , so I've decided to replace the pair --Q9 & Q11 with 2n3904/2n3906 pair.
The footnotes on the schematic state that the PNP should be matched to 10-20mv lower than the NPN @ 200MA.
With the transistor matching cct provided , how do we do that?
Regards.

[noddyspuncture]

You need to build the transistor matching circuit (hfe checking circuit) that is also detailed in the service manual.

There is a mistake though in the PNP version - it is missing a 10K resistor, which you do need to add.
There is a corrected copy somewhere, searching this forum might bring it up...?

Cheers,
Tom

[spuddo]

Hi Tom , that's the cct I'm using to check Vbe matching,
The error you noted has been the subject of much discussion in the past on a few forums----the conclusion by people way smarter than me , was fixing the error did little if anything to the test results.
Maybe Bob was right.
The real reason for the question was to understand why the "200 Ma" was stated in the footnote.
I'm surprised no EE's have chimed in-----Where's MC when you need him?
Regards and thanks for your reply.
Regards

[noddyspuncture]

Well then, don't question it... if you're hfe testing circuit is working... just sort an NPN at 200mA and a PNP at about 185mA and you're sorted..!?

No...?

Cheers,
Tom