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Progress!!!

I recomend that you use high quality polester caps in the monostable timing ciruits, C35 C37, C38 and C39, as their better tollerance will ensure that the correct one-shot timing adjustment is achievable wth the BOM listed resistor values for R8, R14, R15 and R20.


Also, you need to add a 5v wire link to pin 14 on J3(data separator connector).
Some of the through holes for resistors R22 to R39 are undersize and you will need to use suitable, "thin lead" ¼W resistors.

Other than this the 610 build is quite straightforward.

I have for 35 and 38, I'll have to check the others. Thanks for the advice

Yeah, my other caps are good

Looks like all my remaining parts arrived. One problem though, I just had a tooth extracted and feel too crappy to continue building...

OK, so despite feeling poorly due to a tooth extraction, I managed to progress:


And here with a trial fit of the data separator:


Just need to fit the connectors to the data separator now.

Next I think will be a smoke test with the bench PSU of the 610 without the IC's installed to check for shorts, though I will do a manual scan first to make sure everything is soldered and there are mo bridges.

Great progress!

HOWARDHB wrote: ↑Fri Apr 11, 2025 3:28 pmGreat progress!

Thanks. The DS connectors are now done, but I had an eye exam earlier, and coupled with my tooth extraction, all bets are off for any more tonight

Hopefully over the weekend

OK, so all the smoke tests passed just fine, nothing out of the ordinary I also checked for 5v at each and every socket and all was good too.

Annoyingly though, I missed some ICs from my order and on opening the packet, the N8T95Ns are actually N8T126N's so I had to order some more

I did also get the 600 => 610 cable made, so if I get a chance tomorrow I'm going to to a test assembly and work out the 5v power feed from the mainboard to the 610.

All good progress.

Tested physical assembly today:


And it's looking good. Just need to fit the Molex power plug to the mainboard to feed the 610 board.

I can't power on yet though as I have missing IC's, but will hopefully have those soon

Hey Howard (Or anybody else who reads this...

When I was done playing with the physical assembly of the 600/610 combo I took the 610 off but I left the short 40 pin double ended cable in like this:


However on boot, I got this:


So no 610 attached, just the link cable.

Now when I unplug the cable, the 600 works just fine and dandy, and I'm just wondering if there is a possible explanation for this, since having tested the cable, all the pins are connected correctly and there are no shorts between pins.

With the cable being good, it is literally just extending the socket from the OSI600.

I'm thinking the capacitance of the cable just hanging in mid air is causing strangeness, but if anyone can explain I'd be very happy to listen!!!