Recent content by matelot

  1. matelot

    Help with De Morgan's theorem

    I didn't indicate that the TS's actually turn on their own latches, i.e. TS1 turns a latch on that TS2 turns off when it turns its own latch on, TS3 turns TS2's latch off when it turns its own latch on. While ever there is a train in-between track sensors the TS it passed is active. I suppose it...
  2. matelot

    Help with De Morgan's theorem

    now I am even more confused. I was thinking that the way to process the equation is to NOT all the AND's (or single expressions) as in A = B + C * D to A = /B + /( C * D ) Then change all the OR's to AND's as in A = /B * /(C * D). So you finish up with A = (NOT B) AND (NOT (C AND D)) this...
  3. matelot

    Help with De Morgan's theorem

    I am not limited to NAND gates but I seem to remember when you had finished using De Morgan’ s theorem you finished with a circuit containing NAND gates.Maybe I am wrong. Are you using the + sign to indicate AND and the * sign to indicate OR? I seem to remember + being OR and . being AND. I...
  4. matelot

    Help with De Morgan's theorem

    I am looking for help with using De Morgan’s theorems for solving a circuit problem. I learned about De Morgan’s theorems in classes about 35 years ago but have not used them since. I now help run a garden railway as part of a Society of model engineers. I have written a programme for an...
  5. matelot

    do you know these resistors?

    Yes Kris the capacitor you see on the pictures the c4 .22micro (orange one) is a replacement. The original was a paper one that had blown the side out. I bought a pack of fusible resistors from the e-bay (pack of 10) I have been there before. Would you think the bc 182l could be...
  6. matelot

    do you know these resistors?

    Hi Kris, the fused resistors came today. I decided to use a BC182L I have a few in stock but no BC182LB. I checked both electrolytic capacitors and both were duff so I replaced them. If the level at V+ is 240v should c3 be 240v working? I have a little tester unit that allows me to just...
  7. matelot

    do you know these resistors?

    WOW Kris that's a lot of information. Thank you very much. I will get the components you mention and try it.
  8. matelot

    do you know these resistors?

    Hi, I removed the solder from one of the pins of the relay coil and measured 4.6k Ohms across the coil. I can't give you any better idea of the wiring it is just four wires that come out of a trunking to connect onto the board before it is put in a small box near the fan. Bob.
  9. matelot

    do you know these resistors?

    Yes Kris the cap next to the BC212LB is C5 and it is 1nF (102). I confirm that C1, D5, D6, R4, R5, R6, R10 are all missing, due to the fact that trying to understand the circuit and using circuit wizard I was adding components in and removing components. I have assigned the components myself...
  10. matelot

    do you know these resistors?

    I am sorry Kris I made quite a few changes to the drawing trying to make sense of it myself. I have added a new circuit diagram. C2 is the 100microFarad 63v C3 is the 10microFarad 63v C4 is the 0.22microFarad 250v orange one C5 is the 1microFarad. D7 is the 1N4148 and not a zener as on the...
  11. matelot

    do you know these resistors?

    I have enclosed two photos. I would be impressed if you could produce a circuit diagram from this. I have put D7 as a zenner on the drawing but I am quite sure it is a 1N4148, I can just see it marked. C4 also destroyed itself but I replaced it with the orange one you can see, it was still...
  12. matelot

    do you know these resistors?

    Gentleman, Thank you for your prompt replies. I have a confession to make, I was busy doing other things and just posted the thread on the off chance. I am surprised how well you replied. The problem is I am now away from home and won't be back in my study (where the board is) until the 20...
  13. matelot

    do you know these resistors?

    I have a bathroom fan delay circuit that has burned out two resistors. I have tried to simulate the circuit on Circuit Wizard but no matter what value I use the relay never closes. Is it possible Circuit Wizard is not simulating an AC circuit closing a dc relay? Would someone be able to tell me...
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