I would replace all of the outputs in this channel.
If you don't make contact with the bias transistor while the solder is molten, it shouldn't move. It's tiny so it's difficult to clamp. The 3-terminal connector can be clamped but if you're not going to do a lot of repairs, it's not worth the cost of the clamps.
If you don't make contact with the bias transistor while the solder is molten, it shouldn't move. It's tiny so it's difficult to clamp. The 3-terminal connector can be clamped but if you're not going to do a lot of repairs, it's not worth the cost of the clamps.
You'll have to decide whether to order extras or not. If you don't get the outputs too hot, they shouldn't be damaged when you replace them. Clamping them prior to applying power and having a 10 amp fuse in the B+ line will help protect the transistors if there are other faults. I'd suggest ordering driver transistors in case they're damaged. You may also need to order a new gate resistor if you damaged/lost the other one.
Have you read the following post (#29)?
http://www.diyaudio.com/forums/car-audio/148420-t30001bd-schematics-3.html#post1901581
Have you read the following post (#29)?
http://www.diyaudio.com/forums/car-audio/148420-t30001bd-schematics-3.html#post1901581
I take it Q226 & Q227 are the driver transistors?
I was able to reinstall the gate resistor without damage.
I think I will order an extra set of each just in case.
Yes I read that post and will be following your recommendations on removal & installation.
edit : Will the pzta56_q work. The pzta56 is on back order.
I was able to reinstall the gate resistor without damage.
I think I will order an extra set of each just in case.
Yes I read that post and will be following your recommendations on removal & installation.
edit : Will the pzta56_q work. The pzta56 is on back order.
Last edited:
You can try powering it up without the new drivers.
If you have to replace them, apply additional solder to all 3 legs and the tab. Heat the tab for ~2-3 seconds after the solder is molten then move the iron to the 3 legs (heating all 3 at once). The transistor should slide off of its pads. Slide it to a vacant area of the board or lift it up off of the board. Do NOT slide it on top of any other components. If you do, it will freeze on them and will be difficult to remove. If you have Kapton tape, you can lay it down over the adjacent components to give you some place to slide the transistor onto (assuming that there isn't sufficient vacant board around the transistor).
To reinstall, desolder the pads for the 3 leg with desoldering braid. Heat the solder on the pad for the tab of the transistor and when the solder is hot enough, slide the transistor into the molten solder. Then solder the remaining terminals.
If you have to replace them, apply additional solder to all 3 legs and the tab. Heat the tab for ~2-3 seconds after the solder is molten then move the iron to the 3 legs (heating all 3 at once). The transistor should slide off of its pads. Slide it to a vacant area of the board or lift it up off of the board. Do NOT slide it on top of any other components. If you do, it will freeze on them and will be difficult to remove. If you have Kapton tape, you can lay it down over the adjacent components to give you some place to slide the transistor onto (assuming that there isn't sufficient vacant board around the transistor).
To reinstall, desolder the pads for the 3 leg with desoldering braid. Heat the solder on the pad for the tab of the transistor and when the solder is hot enough, slide the transistor into the molten solder. Then solder the remaining terminals.
Powered up amp and everything seems ok. I get clean sound out of both channels.
Tested voltage across emitter resistors & have 0v.
I did not move bias pot from its original setting.Is this normal?
Don't know if this is relevant or not,but they had been readjusted by Rockford previously. This was done when it was still under warranty. They replaced power supply & outputs on same channel.
I ran the amp for about 10min at moderate level with no problems
All outputs stay cool.
I have not tried running it hard yet. Wanted to make sure there was not anything else that needed to be done.
Should I run it tell amp heats up & do more testing, or leave it as is?
Tested voltage across emitter resistors & have 0v.
I did not move bias pot from its original setting.Is this normal?
Don't know if this is relevant or not,but they had been readjusted by Rockford previously. This was done when it was still under warranty. They replaced power supply & outputs on same channel.
I ran the amp for about 10min at moderate level with no problems
All outputs stay cool.
I have not tried running it hard yet. Wanted to make sure there was not anything else that needed to be done.
Should I run it tell amp heats up & do more testing, or leave it as is?
That looks OK. The ones with 0.005v are a bit high but if the amp doesn't run hot at idle, it's not a problem. I'd suggest that you get the amp hot and recheck the voltage across the 0.1 ohm source resistors while it's hot. If the voltages are still approximately what they are now, it would appear to be working properly.
I ran amp for about an hour & retested all source resistors. 1 or 2 changed only by .001.
Tested outputs for DC voltage it also stayed the same.
I will install in truck tomorrow and see how it holds up.
I want to thank you very much Perry you are a great asset to this site!!!
Hope I can be of help someday.
I will post back if I have any more problems with this amp.
Tested outputs for DC voltage it also stayed the same.
I will install in truck tomorrow and see how it holds up.
I want to thank you very much Perry you are a great asset to this site!!!
Hope I can be of help someday.
I will post back if I have any more problems with this amp.
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