Search results

  1. B

    Stage Line 500W amp repair project

    Would it be possible to connect an input signal straight to the right side amplifier and cut out the normal input stage ?, my reason is to try work out if the distortion is pre amp circuitry or the actual amp ?
  2. B

    Stage Line 500W amp repair project

    I think this amp is cursed , although the right chanel seemed to be working ok yesterday it, now sounds terrible, like its over deviating, even with the imput signal low, so annoying!!
  3. B

    Stage Line 500W amp repair project

    Yeah that was my thought's to
  4. B

    Stage Line 500W amp repair project

    Sorry bit am not sure what youu mean, basically i fitted the outputs and connected a small speaker to the output just to see if there was amplification, left side does produce sound but no more than the input when on full gain, right side is much louder , Pete
  5. B

    Rest in Peace, Kris

    Almost finished this now adam, only taken me about 5 years
  6. B

    Stage Line 500W amp repair project

    Still need to be removed, cleand and pasted before final fitment
  7. B

    Stage Line 500W amp repair project

    No nothing was removed, the 4 main outputs are now in, used 2 of the old ones to test first as 3 of them still tested ok, now i have amplification on the right side but not the left, the left chanel has the old main outputs, Q10 and Q20, and yes negative probe on t20
  8. B

    Stage Line 500W amp repair project

    Ok Q1= 0.370VDC and Q22= --0.782VDC
  9. B

    Stage Line 500W amp repair project

    I will check this tonight after work and post my results
  10. B

    Stage Line 500W amp repair project

    However i may fit these later, and also the missing output transistors
  11. B

    Stage Line 500W amp repair project

    No, if you look on the schematic it says NF, (NOT FITTED )
  12. B

    Stage Line 500W amp repair project

    Its the 4 clipped to the heat sync and the main 4 output transistors
  13. B

    Stage Line 500W amp repair project

    Also, npt sure if its that important but all the output transistors now have 64v to each base terminal
  14. B

    Stage Line 500W amp repair project

    Tried to clean the board up a little
  15. B

    Stage Line 500W amp repair project

  16. B

    Stage Line 500W amp repair project

    Ok, so Q10 and Q1 replaced, all looks good, all power cables attached and no fault lights anywhere , tempted to fit the output drivers ?
  17. B

    Stage Line 500W amp repair project

    If am honest, i dont see where the 55v input is, apart from to the psu as both sides has an ovpl and + and -, am i right in thinking the OVPL is over volt protection ?, but seeing as the fuses all have good voltage to the left and right chanel amps am not sure why i would need to do this, i...
  18. B

    Stage Line 500W amp repair project

    Wow, lots to take in there, i have ordered some new mpsA42 transistors and some more kit, ie new temp controled iron with different tips, solder wick and flux, i am determined this amp will live again, Thank you to everyone who is interested and willing to help with this project, Pete
  19. B

    Stage Line 500W amp repair project

    Will these do as a replacement ? https://www.ebay.co.uk/itm/10-x-MPSA42-NPN-High-VoltageTransistor-TO-92-Silicone-300V-500mA-/232562261199?_trksid=p2349624.m46890.l49292
  20. B

    Stage Line 500W amp repair project

    Ah ok, so as long as there MPSA42, they should be good, also think Q10 is dead, but again, going to have to remove and test out of circuit, i am trying to test as much as possible before i stick an order in , Cheers
Top