For clarity...
1A is an MMBT3904 the 2A is an MMBT3906
1GM is an MMBTA06 the 2GM is an MMBTA56
Either of these will work as power supply drivers.
1A is an MMBT3904 the 2A is an MMBT3906
1GM is an MMBTA06 the 2GM is an MMBTA56
Either of these will work as power supply drivers.
Ok so I installed the new drivers and removed those jumped pads on the board. Now I can't get the board to power up to check the drive signal.
Follow the remote circuit and make sure its getting to the 494.
Check D703, Q701 and Q702. I believe pin 12 should have the remote voltage on the 494.
Check D703, Q701 and Q702. I believe pin 12 should have the remote voltage on the 494.
Perfect thanks sean. I did replace the 494 already. I'll check all that. That is exactly what it acts like. There is 12v on the source legs of the 3205's.
Trying to get drive signal on the ps mosfets. And the drivers we're burnt to the board.
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TL494
I must say to you that i never need to replace the tl494 on any Rockford Fosgate amplifiers. i am talking about more then 20 years dealer service in my country.
But, there's always a first time 😀 😀
yes the P.S MosFet and the gate resistors and the drivers burned but the tl494? never. anyway i hope you will solve all the problems
I must say to you that i never need to replace the tl494 on any Rockford Fosgate amplifiers. i am talking about more then 20 years dealer service in my country.
But, there's always a first time 😀 😀
yes the P.S MosFet and the gate resistors and the drivers burned but the tl494? never. anyway i hope you will solve all the problems
I've been repairing Rockford amps for roughly 15 years and have had to replace 494 about a dozen times or so. Its not very often but they do fail.
I just replaced it out of desperation really I can't find anything opennor out of tolerence. I have 1.2v at pin 12
That's not enough, you need 12v. Find out where between the remote terminal and the 494 pin 12 your losing voltage.
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