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"Cigar Box" Amp
#6
Hi Jim

You have the output transistors swapped.

The numbers on the packages are very faint - as they do it now with lasers instead of ink - and it also looks like maybe you used flux remover that might have obscured some of the printing on them. Fortunately there is a C still visible which is the NPN device for position QN6; thew A is PNP for position QP7.

You can do a resistance check on each device from E to C and hopefully this will read high - at least not-zero. You may be able to swap them into their correct places and have it work provided you can extract and resolder them without overheating them. I can send you a new pair.

There is also a solder tail or slash on the bottom of the board in the upper right corner. Check what that is.

Have fun
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Messages In This Thread
"Cigar Box" Amp - by galejt - 07-18-2022, 02:00 PM
RE: "Cigar Box" Amp - by K O'Connor - 07-18-2022, 02:54 PM
RE: "Cigar Box" Amp - by galejt - 07-19-2022, 03:23 PM
RE: "Cigar Box" Amp - by K O'Connor - 07-20-2022, 03:29 PM
RE: "Cigar Box" Amp - by galejt - 08-26-2022, 03:18 PM
RE: "Cigar Box" Amp - by K O'Connor - 08-26-2022, 08:33 PM
RE: "Cigar Box" Amp - by galejt - 08-27-2022, 02:03 PM
RE: "Cigar Box" Amp - by K O'Connor - 08-27-2022, 03:51 PM
RE: "Cigar Box" Amp - by galejt - 08-29-2022, 01:50 PM
RE: "Cigar Box" Amp - by K O'Connor - 08-29-2022, 05:04 PM
RE: "Cigar Box" Amp - by galejt - 06-04-2023, 05:04 PM

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