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

Thanks Martin for the feedback, I found some 8k flash roms, mostly pin compatible with the layout this specific board have without do any changes to it. 3 pins have to be routed to other places, so i think i will give that a try one day ;) //CLAUS. That won't work, with the chip select to rom B (CSB...

yes of cause ;) A11+A12 should be present for the 8k, I must be sleeping :) But are all the 3 rom sockets not connected to the adress and databus all the time ? so if A13 and A14 is used as extra chip-selects ? Could this larger chip not just be connected to any socket then ? so if the chip is progr...

Hi Mark, yes it looks the same and also the same rom chips used. I checked with multimeter, and i found out the layout from the rom socket to the z80 (A0-A10) and (D0-D7). looks quite standard compared to some flash chips W27C512 I have in stock. So I wonder if you actually could flash one W27C512 (...

This mainboard came from (another) MTX which had power issue after replacing the power regulators and the TIP, and the diods i get normal voltages at the 4116, +12,+5v,-5v. The eproms TI 25P64 are in very bad condition, so I actually dont want to put them back in to the mainboard. The problem is I h...

Hi guys have a 4000-05 board, not sure why but it came with 25p64 Eproms. And some yellow wires at the back of the pcb to route the signals from those eproms, i dont see any cut traces, wonder if i can just remove this "mod" and put in roms from another 4000-05 board. Wonder why they did t...

Ok I will check that out later ;) I'm no expert on the power supply, but the -5v supply is "generated" by ZD3. Whether you problem is a busted ram shorting -5v to ground or the zenner itself going up in smoke, I have no idea! C49 is also across the -5v supply a short there wouldn't be good...

Update. One of the big 4700uf caps, was bad or maybe bad soldered, so now it get some kind of voltages, but no "Ready Prompt".
+12V is like +11.30
+5v is -5.01V
-5v is +0.5v !!!!!!

I swapped z80 cpu, and ctc with no better result.

Hi I did some repair on a 4000-05 board, replaced the power regulators and the tip. I removed all socked ics. The 5v line seems to be quite low, the PSU i known to be good and work on another MTX, the VRAM gets burning hot after very short time. Could it be a short in one of the vram ics ? It seems ...

Hi That sounds fun too. Anyway we still have some time. There are a lot of suggestions, I would prefer something close to a larger AirPort, since I would come in from LHR or Gatwick I guess. The other possibility is perhaps getting hold of the chap from RMC the Cave and trying to set up a special we...

I could possibly host a one-day event second half of October or sometime in November. My biggest reservation is that I don't actually have much Memotech kit: an MTX 512, 3.5" SDX, DMX, and a few Rarpberry Pi's running MEMU. Or as another alternative, we could all join Stephen Usher at the Cent...