You know, I never thought I'd be writing a log entry about connectors. How hard can it be? Turns out, it can be pretty hard when you're reverse-engineering someone else's design!

Other than the buttons board and the case (with speakers) the only things I'll have to deal with from the original system are the connectors to these components.

Mains

The mains input connector is very specific in height and style. I can't find a replacement it, so I'll remove it from the original board. I'll have to measure it carefully and build a footprint I can use on the PCB.

Transformer

The transformer uses an 8mm connector with rounded pins and extra spacing between pins 1 and 2 for polarization for it's input connector. There aren't many 8mm spaced connectors and I've been through as many as I can find without success. I'm going to remove the old connector from the transformer and install a new one from Molex on the input side of the transformer.

After some research, the output connector (6 pins) is fairly standard. While I don't know the manufacturer of the original, I've found a substitute readily available on DigiKey and Mouser: 1744057-6 from TE Connectivity.

Speakers

The output from the amplifier to the speakers uses the same style connector as the output side of the transformer, so I can use 1744057-4 also from TE Connectivity, the same connector with four pins instead of six.

Top Board

This only leaves the front panel that mates with the top board. The connector on the front board is perfectly aligned, uses 2mm spacing and the body of the connector has very specific shaping. The connector on the top board is not something I can replace so I need to find a replacement. The good news is that after much research I've tracked it down, it's an eMQ connector from JST - a side-entry type header. The bad news is that it's no longer manufactured and after some inquiries, there doesn't seem to be any old stock. I've had to remove the connector from the old board (which fortunately wasn't an issue - it came right off). Since I can find the datasheet for it, recreating the footprint should be simple.

All I have to do now is make sure the connector is aligned to a fraction of a millimeter or the top panel won't align.