Do you have a proper PWM signal (10v amplitude, going fully down to the negative rail) on pin 1 of the IC?
When trying to check the signal on pin 1 of the 21844s the amp will start squealing and draw excessive current
Ok I found an issue with this amp .
R280 burnt the leads off it I’m assuming when the cap went bad .
Do you happen to know the value of this resistor in pic 2?
The schematic shows it as a 220k in that location but these resistors were original when I got the amp .
R280 burnt the leads off it I’m assuming when the cap went bad .
Do you happen to know the value of this resistor in pic 2?
The schematic shows it as a 220k in that location but these resistors were original when I got the amp .
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The resistor is marked 100k. You should be able to measure it. The entire endcap is connected to the terminal. Scrape the end and measure it.
The value of R281 is also different so I'd go with what the markings are on this resistor.
The value of R281 is also different so I'd go with what the markings are on this resistor.
Amp is put back together and up and running finally !!
Thanks for all the help greatly appreciate it
Thanks for all the help greatly appreciate it
I'd suggest putting this on a power supply and letting it idle or play at a low level for many hours. If you don't have to reinstall it, power it up whenenever you're in the shop. Do this for a week or more.