I took apart two cables so far and both of the crimped ends have different spacing compared to what DogP has laid out on the PCB.
Can you post a picture of what the IDC connector looks like? I've seen two different spacings, but had no problem getting both of them into the adapter (one had all 4 rows equally spaced, the other had the top two and bottom two rows slightly closer to each other). Curious what others are out there.
Once the PCB is soldered on, am I still able to use the 68-pin connector for CD-ROMs without resoldering DogP's PCB? In viewing the traces, it seems like this should be OK.
With the 50-pin adapter installed, you won't be able to use the 68-pin connector, since it terminates the upper byte. Well, to clarify - you won't be able to use the 68-pin cable in 16-bit mode at least, since the upper byte is shorted together and pulled to TERMPWR.
a) do you know if your upper-byte-terminated-adaptor needs to be on the end of the SCSI cable, e.g. just before the terminator block, or can it be somewhere in the middle of the SCSI cable, with say, other devices downstream of it?
It shouldn't matter where it is, since it's only intending to terminate the upper byte of the device (16-bit capable device running in 8-bit mode), not the entire cable. Not sure if it's clear, but a 50-pin SCSI ribbon has 8 data bits, and a 68-pin ribbon has 16 data bits. So, if you're connecting everything with a 50-pin ribbon cable, you're only using an 8-bit interface, and the upper byte which may be terminated at one device is completely unconnected at another device because those lines aren't connected through the 50-pin cable.
b) I was planning on setting up a system which has ACARD on CD-ROM, ACARD on CF, and a SCSI ZIP drive. Do you think the ACARD-CDROM unit needs one of your adaptors as well, or will a simple 68pin-to-50pin plug suffice? See attached photo.
I'm not familiar with that other adapter you have... if it's wired correctly, it should function identically to my adapter. The problem I ran into was the couple of 50 to 68 pin adapters I tried incorrectly terminated the upper byte (e.g. connected to GND), which caused the device to not work. If the adapter you have works with the CD-ROM alone, I'd expect it to work fine with the whole system.
DogP