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valvestate 8080 blows fuse
i have valvestate 8080 that i purchased broken. the original owner said the pots were noisey so he had attemped to clean them. but broke one in the process. parts of the amp were still off when i got it home. when i removed the amp chassic i found 5 pots where broken off the board. i ordered and replaced all 5 pots . when i plugged up the amp to try it for the first time i could smell something burning then with in 3 mins i had smoke comming off the 2 blue resistors that sit near the tube. i also noted the board was very scorched under them when i was replacing the pots. of course with minimal knowlege on diag a electrical circuit i elected to try a 12ax7 tube . it was glued into a black boot over the tube socket so i had to remove the socket from the board and replaced it with a new one. got the socket in and turned on the amp . no more smoke . let it run for 30 min and then plugged in my strat. all channels worked lights and pots worked , reverb worked , but the amp was distorted on all channels . sounded somewhat like my mesa did when it blew the power tube. ragged to say the least. so i go to the the local abec electronics store and purchased a nte270 nte271 and nte291 op transisters and driver transister. i crossed them over from tip142 tip147 tip29c . after i installed them when i turned on the amp it made a minimal hum with nothing plugged in the hum got a little louder with 15 sec and snap the fuse blew. the transisters got pretty hot in that 15 seconds . before i put then in the amp it would stay on and play just sounded terrible, now with new transisters and driver it pops the fuse as soon as i turn it on. i did insulate all the transistors i did put the pnp and the npn in the correct spots . i dont know if the nte transisters are correct for the amp now or if something else had gone south in the amp before i bought it and wipped out the original transisters and now distoryed my new ones. i wouldnt think so thow because after i put the new tube in it , it played and didnt blow fuses. if anybody can help with some imput it will be appreciated greatly . thanks Davo