Leaderboard

this is the pack of equivalent direct pinout BC183L transistors I bought to get some for the jpm impact new cards, they are of course brand new!

This one had me dancing! On switch on it wouldn't initialise correctly, funny noises from the speaker, no motor drive and random lamps flashing whenever switches were operated. With faults like this it's difficult to know where to start. All Data and Address lines were good so suspicion didn't fall on the CPU. Could it be faulty RAM? I've had something similar before but not quite the same. The 5v rail was clean and stable and so depressing thoughts were abound thinking I'd have to swap out all the PIO and RAM to see which one (or more) was causing it. Before doing that I'd thought I'd just check the power was getting to all the chips, which it was. It may have been a lucky hunch but I didn't think IC3 was getting as warm as the other PIO's (6820) not that any of them were really warming up. With this in mind I checked the ground pins of all the PIO's and blow me IC3 had about 1.5v on it!! The track next to it was 0v and looking on the track side I found this. It's not easy to spot which is why I missed it when I went round resoldering all the connectors. In case you don't spot it look at pin 1 which is the top right hand side of the 40 pins. Hopefully you can see the solder ring. Once resoldered it ran sweet as a nut. So this time I was lucky I reckon.

Yours is definitely 1994 and yes the top side is lighter in colour with the solder mask to the underside, but it is the same as ones I have here from 1994 which are darker, so quite possibly when the solder mask was screen printed on it was running out??? but the track layout is the same, here are 2 of mine that are from 1994, one is lighter in colour than the other on the green solder mask

Both as bad in my opinion, different tracks get eaten away but same result in card not booting

Emulation? Looked it up seems like £15 Roms are emulated not the £25. Going through all my decals and Roms today. Posting what I find

I’m sure I’ve the sound roms for this I’ll check it out laters

Dont think it has been emulated. Not sure if the roms are in the Dat. This may be due to the fact some Epoch machines will not run without the sound roms. Some will.

We’re not in shed 😅 ok found stand and deliever Roms but no sound Roms, and they are 4 Roms not 2 so not ideal for testing tbh.

Assuming your needing epoch Roms?

Read all. Well worth it he sent this.so he sends this photo after..

can always change the roms to a different game then you've no idea what's going on.

Oh and when they are running good, the machine should twitch reels to start boot sequance in about 10 seconds with a good battery on. bit longer maybe if ram has been cleared. Where as cards just about running can take 30 seconds+ to do it. suppose it's all the green on the security chips

Quite a buzz when they boot up. even better when they stay running. Don't forget to check the on and off battery current. looking for about 0.002mA when off and over 0.4mA when on - more with a decharged battery. Should be fine if you've swapped out the 3 ZTX transistors near the battery with new, but sometimes (on MPS) the fly wire isn't making good connections at the board end. Always best to measure the current, and off voltage across the ram.

nice one matty there will be no stopping you now mate happy days

Decals will be destroyed as soon as water touch’s the art work. Roms will probably be fine,