Hi there,
I just picked up old school amp rockford fogate 650 mosfet. I tested it for first run and notice that the amp sounds noisy. The fan were turned on since the amp were turned on even when the amp still cold.
What i'm gonna make sure is. Is it normal that the fan turned on all time even the amp still cold?
I got a few pics of my amp.
Thanks alot before
I just picked up old school amp rockford fogate 650 mosfet. I tested it for first run and notice that the amp sounds noisy. The fan were turned on since the amp were turned on even when the amp still cold.
What i'm gonna make sure is. Is it normal that the fan turned on all time even the amp still cold?
I got a few pics of my amp.
Thanks alot before
Attachments
'Cold' can cover a wide range.
The transistor indicated by the red arrow needs to be tight against the heatsink with heatsink compound filling the gap between the body of the transistor and the heatsink.
The pot with the green arrow adjusts the threshold point. You can set it for any temperature that you feel is suitable for the fan to start. I'd recommend about 85-90F. You don't want the amp to get too hot before it starts. The fan doesn't move a lot of air.
The transistor indicated by the red arrow needs to be tight against the heatsink with heatsink compound filling the gap between the body of the transistor and the heatsink.
The pot with the green arrow adjusts the threshold point. You can set it for any temperature that you feel is suitable for the fan to start. I'd recommend about 85-90F. You don't want the amp to get too hot before it starts. The fan doesn't move a lot of air.
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I don't know what idle current should be. Seankane may know what to expect.
Most of the idle current is likely from bias current in the output stage. If you don't have a scope, adjusting them is difficult because the output stage can be noisy if under-biased and can very easily be over-biased.
Most of the idle current is likely from bias current in the output stage. If you don't have a scope, adjusting them is difficult because the output stage can be noisy if under-biased and can very easily be over-biased.
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