punch 45HD transistors?

[damage]

Trying to replace Q10 and Q11. They are marked as Motorola ss236. What are suitable replacements?

Also, just out of curiosity, what about ss234?

Thanks!

[Perry Babin]

If all of the outputs have the same part number, IRF540s are a good substitute.

If the outputs are complementary, the IRF540/9540 are good subs.

If you have a good transistor of each part number, you can determine what they are. If there is complete isolation (infinite resistance) from pin 1 to the other pins no matter the lead placement, they are FETs. If you short pin 1 to pin 3 and the transistor shows ~0.5v drop on diode check with the black lead on the tab and the red lead on pin 3 (and is open if you reverse the leads), it's an N-channel. If it passes current in the other direction, it's a P-channel.

Where are the SS234s being used (power supply/audio)?

If you can't figure it out, you can get a schematic from Rockford on Monday.

[damage]

These particular are power supply. I replaced them with some BUZ11s. Unfortunately, the outputs are shorted too. They are the same transistor too, but I'm out.

The ss234 are in another rockford's power supply.

Very strange are rockford had very little consistency. Was this fairly common?

[Perry Babin]

They were probably making changes to use better parts as they became available. They were also making the transition from BJTs to FETs at the time when these amps were produced. So that may have something to do with it. The Punch 30HD used BJTs in the supply and complementary FETs in the audio amplifier.

[damage]

I think I bricked it anyways. I saw some magic smoke get out.

[Perry Babin]

Where did the smoke come from?

Does the preamp board (behind the RCA jacks) have any corrosion on it (near the electrolytic capacitors)?

[damage]

Dunno, it was just a little whiff. I was welding my rollcage this morning and now I'm doing computer rebuilds. So I haven't messed with it today. I'll probably sit down and order all my parts tonight. Probably won't touch it until Tuesday unless tomorrow's football game sucks.

I replaced the input board with one from ebay.

Power light doesn't come on and I get no current draw. I haven't pulled the specs on the op-amps to see if low-voltage is working.