This amp was previously serviced and all IRF530 outputs of the RIGHT channel were replaced with IRF530N, IRF brand. The Left channel is still running SEC brand IRF530. ALL source resistors of both channels, 5w0.1ohm need to be replaced as some are showing signs of a previous overheat. They're currently measuring in-spec and and so I'm troubleshooting further.
The amp currently works, but the RIGHT channel new IRF530N start to get pretty warm after about 30 seconds not mounted in the sync. The amp only draws between .8A~1.3A, rising slowly as the Right channel FETs start to get hot.
I tried swapping several parts including the networks (MOSAMP1/2), pre-drivers, drivers, bias transistor between Left and Right channels and the problem remains with the IRF530N in the right channel.
Is IRF530N not a good part for this amp, similar to IRF540/540N in other cases?
Long chance but can this amp work with IRF540 or IRF640? I have plenty of those just no IRF530.
The amp currently works, but the RIGHT channel new IRF530N start to get pretty warm after about 30 seconds not mounted in the sync. The amp only draws between .8A~1.3A, rising slowly as the Right channel FETs start to get hot.
I tried swapping several parts including the networks (MOSAMP1/2), pre-drivers, drivers, bias transistor between Left and Right channels and the problem remains with the IRF530N in the right channel.
Is IRF530N not a good part for this amp, similar to IRF540/540N in other cases?
Long chance but can this amp work with IRF540 or IRF640? I have plenty of those just no IRF530.
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Does it do it with the right channel components tightly clamped to the heatsink, including the bias transistor (all with heatsink compound)?
Can you adjust the bias?
Can you adjust the bias?
When I add bias, the IRF530N get hot VERY quickly, but the IRF530 in the left channel dont sweat a little bias out of the chassis.
I removed all IRF530N, and then moved half the Left channel SEC brand IRF530 in place of the removed IRF530N in Right channel, so now each channel has 1/2 bank filled with SEC IRF530. Amp seems to be working just fine, and both channels can take a bit of bias out of the chassis.
I'm going to replace all IRF530 AND Source resistors. I just checked and I dont have any IRF540, only IRF540N. SO I'm going to order the correct parts.
I removed all IRF530N, and then moved half the Left channel SEC brand IRF530 in place of the removed IRF530N in Right channel, so now each channel has 1/2 bank filled with SEC IRF530. Amp seems to be working just fine, and both channels can take a bit of bias out of the chassis.
I'm going to replace all IRF530 AND Source resistors. I just checked and I dont have any IRF540, only IRF540N. SO I'm going to order the correct parts.
Does it do this with the transistors thermally mated to the heatsink and the bias set after they're clamped down.
The problem could be that the replacements are more sensitive to the difference in temperature between the components... And they could be incompatible... but I'd test with everything clamped. It takes less than a minute to slide the board into the sink and to install a clamp or two.
The problem could be that the replacements are more sensitive to the difference in temperature between the components... And they could be incompatible... but I'd test with everything clamped. It takes less than a minute to slide the board into the sink and to install a clamp or two.