Hifonics txi 1500d output transistor !!

Hello..I have a hifonics txi 1500d broken..Amplifiere was burned and i changed the tl494 , driver transistor,power suply transistor ,and driver hip4080, .Now the power suply work good.the problem is at output transitor because when put the power suply on the amplifier , 3 transistor from photo are very hot,in few seconds are at 100 celsius degrees.
If the voltage remains coupled transistors are destroyed(only 3 pcs).I wil put a photo for see.,.i use irf1310 all output transistor.
I wait the sugestion,what i must to check:|thank you anticipate:|:confused::confused:
 

Attachments

  • DSC_8011.jpg
    DSC_8011.jpg
    802.9 KB · Views: 385
  • tranzistori hot.jpg
    tranzistori hot.jpg
    132.5 KB · Views: 368
  • DSC_8016.jpg
    DSC_8016.jpg
    681.5 KB · Views: 367
To avoid running in circles with this amp, I'd suggest installing a new 4080 (no matter if it's currently new) and all of the output transistors with the IRF3710Z. That seems to be the most reliable way to get the 4080 based amps repaired.

Absolutely do not purchase components from ebay. Order from farnell or mouser or some other reliable distributor.

There are other components that need to be checked like the large resistors and diodes near the 4080 and all of the gate resistors.
 
Hi

I checked older posts regarding the IRF3710 / IRF3710Z /IRF1310 topic. If I get Perry correctly he suggests to always replace blown outputs to IRF3710Z ? Is this still up-to-date? I have anotherone of those 1500d´s on the desk right now. It seems that audiodesign (German sales office for hifonics products) replaces the outputs with IRF1310 .... as far as I can see this amp has been repaired already in the past. So it seems on the long run IRF1310´s will probably also fail over time. Overhere I can also get IRFP3710Z , those have the same characteristics as IRF3710Z (I belive they have the same datasheet) but allow higher currents and a little bt more power diddipation, probably due to their larger housing. Would it be recommendable to use those ? Thx, Stephan