*** M E M O R U M ***

It's alive!!!! Great news guys, everything works! I got the mono minijack cable today and I managed to load a game without issue. Still had the sound problem, so I switched out the octal flip-flop and the sound works now! With fart sound in Blobbo and Knuckles aswell, which was pretty much my criteria for success. Haha, this is so awesome!

Thank you all for your generous help, I really, really appreciate it.

I plan to make some videos soon'ish of a bunch of gameplay. I know some already are on Youtube, but the more the merrier I think.

Well done

It’s always good to get that warm fuzzy feeling when a ‘broken’ system fires up and works after some TLC

Mark

Absolutely! I have to admit I was a bit hesitant to turn it on when I was done, as I had accidentally scratched a connection I couldn't see below the flip-flop IC when gently prying it off the board after desoldering. Fortunately it was only a surface scratch, phew...

If you are going to scrap the chip that you are removing - as in this case, It is often a good idea just to carefully snip the legs off the IC first before desoldering the pins. Much less chance of damaging the PCB that way.

Use fine nose snips and cut close to the IC body.

I will definitely use that method if there is a next time. Thank you for the suggestion.

Also a trick is to desolder from both sides, dont know if its works on the Memotech but I removed 8x 4116s from a ColecoVision board, the trick is to cut the legs off the ics. And then desolder from the legs-side of the board, and remove the legs with a tool. then later use a solder pump and heat the solder from both sides, until you get a clean hole. And then use SOCKETS next time

Dave wrote:If you are going to scrap the chip that you are removing - as in this case, It is often a good idea just to carefully snip the legs off the IC first before desoldering the pins. Much less chance of damaging the PCB that way.

Use fine nose snips and cut close to the IC body.

Crazyboss wrote: ↑19 Oct 2018 15:32 Also a trick is to desolder from both sides, dont know if its works on the Memotech but I removed 8x 4116s from a ColecoVision board, the trick is to cut the legs off the ics. And then desolder from the legs-side of the board, and remove the legs with a tool. then later use a solder pump and heat the solder from both sides, until you get a clean hole. And then use SOCKETS next time

Yes, I socketed it Just in case I need to switch it again later.

Lars you changed the SOUND IC ?

As I understand it, he renewed the octal flip-flop (removed the 74LS374N chip and fitted a new SN74HCT374N) that feeds the sound chip with data. That fixed the problem.

Mark

Crazyboss wrote: ↑01 Nov 2018 11:47 Lars you changed the SOUND IC ?

No, only the octal flip-flop that feeds data to it - and it works flawlessly now. Currently creating videos of all the games I can get to work.