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Showing content with the highest reputation on 09/28/21 in all areas

  1. I may have a lamp board and alpha would need pics of your old alpha though Ronnie
    1 point
  2. EBay, Facebook groups or check locally and break a cheap broken Epoch machine for spares of everything
    1 point
  3. Could be the lamp board (most probably the socketed pic chip if it's the mk1) or the alpha display itself. I'd try a whole new lampboard first. You mustn't unplug anything in the lamp board, alpha display, or the grey serial link with the machine switched on. That can blow any of the above or take out the serial driving on the main board (nightmare scenario).
    1 point
  4. Nice one Talisker 10-Year-Old Single Malt Scotch Whisky Spirit type - Waitrose Cellar
    1 point
  5. It's been a while since I wrote an MPU3 fault up. Just when you think you've seen it all yet another one comes along to bite you in the bum? This one came in as not working/untested and after the usual suspects had been swapped out I noticed that IC23 (74LS08) was burnt! Swapping this out and then powering up on the test rig I was pleased to see the reels moving and the lamps flashing. The triacs were all pulsing correctly too. So moving on to the switch test and ....nothing?? Now IC23 is fed from IC11 (74LS138) and here there were no outputs because there were no inputs! Hmm what's going on here? The inputs to this chip come from 3 of the 6821's IC3,4 & 5 and there was nothing leaving on all three on pin 39. A quick resistance check to ground showed 2.1 Ohms 1k Ohms and open circuit (should be approx 5K) so although all 3 PIO's were working in their other functions all the pin 39's had popped!! What a bummer. IC21 (9602) is also connected to pin 1 of IC11 and this had also popped. With all parts replaced things were back to normal thank goodness.
    1 point

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