I can't see enough detail on the transformer.
If only 1 winding (the terminal winding) is shorted, you may be able to desolder it and insulate it with heatshrink tubing or Kapton tape to prevent it from shorting. If there is more significant damage, you will have to get a replacement transformer from Rockford or rewind the one you have.
If you have replacements for the driver transistors, replace them and measure the gate voltage again.
If only 1 winding (the terminal winding) is shorted, you may be able to desolder it and insulate it with heatshrink tubing or Kapton tape to prevent it from shorting. If there is more significant damage, you will have to get a replacement transformer from Rockford or rewind the one you have.
If you have replacements for the driver transistors, replace them and measure the gate voltage again.
i measured the voltage on all the pins of the 494
Pin1-- 0 volts
pin2-- 4.73
pin3-- .06
pin4-- .10
pin5-- 1.53
pin6-- 3.43
pin7-- 0
pin8-- 13.17
pin9-- 5.06
pin10-- 5.67
pin11-- 13.17
pin12-- 13.17
pin13-- 5.02
pin14-- 5.02
pin15-- 5.02
pin16-- 0
all reading are with just remote wire and ground hooked up.
Also on the 1a drivers they are showing no voltage on any of them
Pin1-- 0 volts
pin2-- 4.73
pin3-- .06
pin4-- .10
pin5-- 1.53
pin6-- 3.43
pin7-- 0
pin8-- 13.17
pin9-- 5.06
pin10-- 5.67
pin11-- 13.17
pin12-- 13.17
pin13-- 5.02
pin14-- 5.02
pin15-- 5.02
pin16-- 0
all reading are with just remote wire and ground hooked up.
Also on the 1a drivers they are showing no voltage on any of them
ok 1 quick question on this amp is it common or do i have something shorted the power supply fets are mtp75n05hd.
the drain and the source of the fets show 0 ohms between them like they are connected together i took them out and touched the pads.
i still get 0 ohms between the drain and source on the pads is this normal or is something shorted?
the drain and the source of the fets show 0 ohms between them like they are connected together i took them out and touched the pads.
i still get 0 ohms between the drain and source on the pads is this normal or is something shorted?
0 ohms isn't normal.
It could be due to a shorted transformer winding. Clamp your meter probes in the B+ and ground terminals (nothing else connected to the amp). With the meter set to diode check or continuity (wherever it beeps when the probes are shorted), twist the transformer. Does the meter go from showing a short to showing something closer to an open circuit?
If not, the windings may be welded together or have too much pressure between them to break the connection between them when twisting the transformer.
If you're absolutely sure that you don't have a short between the pads on the FETs and the FETs are not defective, pull the transformer (or at least the 4 wires on the secondary. If the short is through the transformer, the short between legs 2 and 3 of the FETs should clear.
It could be due to a shorted transformer winding. Clamp your meter probes in the B+ and ground terminals (nothing else connected to the amp). With the meter set to diode check or continuity (wherever it beeps when the probes are shorted), twist the transformer. Does the meter go from showing a short to showing something closer to an open circuit?
If not, the windings may be welded together or have too much pressure between them to break the connection between them when twisting the transformer.
If you're absolutely sure that you don't have a short between the pads on the FETs and the FETs are not defective, pull the transformer (or at least the 4 wires on the secondary. If the short is through the transformer, the short between legs 2 and 3 of the FETs should clear.
All you have to do is...
Measure the wire so you know what gauge to buy.
Buy it from eBay, Amidon, Surplus Sales of Nebraska...
Remove the windings from the core counting the number of windings and paying attention to the way they're laid down on the core. Photographing it from several angles before removing any windings will help you to remember the layout.
Replace the windings with new wire.
If you don't want to rewind it, Check with Rockford. I think most of their transformers are in the $25-30 range.
Measure the wire so you know what gauge to buy.
Buy it from eBay, Amidon, Surplus Sales of Nebraska...
Remove the windings from the core counting the number of windings and paying attention to the way they're laid down on the core. Photographing it from several angles before removing any windings will help you to remember the layout.
Replace the windings with new wire.
If you don't want to rewind it, Check with Rockford. I think most of their transformers are in the $25-30 range.
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