It remains at 4.00v from 10v to 15v B+ input. When I injected the 14v signal to this pin on earlier test (prior to removing mod) I got +/-46v rails lol I guess that wasn’t save to do.
I think the regulator is functioning but you may need to clamp the FETs and drive a load to see if the voltage on pin 13 changes and the rail remains steady.
Amplifier is powering up good and handling 4ohm mono load at full capability (300watts pulling 53a @ 13.5v). Only thing I notice was it takes a 4 seconds to power up once remote is applied, not a big deal. Thanks once again Perry!
Yes please, I assume 2sec would be max. Also has a bit of a spike in current when powering up unlike any other amp, using a large 200a PS it would pull upon powering up around 6-7a then idles at 1a.
Only thing I see when comparing another 2075AM, was that added revision from factory and an additional capacitor added on the board that I left behind. I removed the transistor/diode/cap that were added but there’s another electrolytic cap on the board that other 2075’s don’t have. Perhaps that may cause the delay. It’s not tied to the soft start pin of 3525.
Only thing I see when comparing another 2075AM, was that added revision from factory and an additional capacitor added on the board that I left behind. I removed the transistor/diode/cap that were added but there’s another electrolytic cap on the board that other 2075’s don’t have. Perhaps that may cause the delay. It’s not tied to the soft start pin of 3525.
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Is the SS terminal used in this amp?
Is the switched B+ to pin 15 or 13 instantly switched on when remote is applied or does one/both have a delay before receiving voltage?
Is the switched B+ to pin 15 or 13 instantly switched on when remote is applied or does one/both have a delay before receiving voltage?
the SS terminal used in this amp? No, it’s floating
Is the switched B+ to pin 15 or 13 instantly switched on when remote is applied or does one/both have a delay before receiving voltage? I’ll check those pins and get back to yout with answer.
The circled in yellow capacitor is the one that remains on the board, other 2075AM’s that don’t have the factory revision added components don’t have that capacitor on the board.
Is the switched B+ to pin 15 or 13 instantly switched on when remote is applied or does one/both have a delay before receiving voltage? I’ll check those pins and get back to yout with answer.
The circled in yellow capacitor is the one that remains on the board, other 2075AM’s that don’t have the factory revision added components don’t have that capacitor on the board.
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Is the switched B+ to pin 15 or 13 instantly switched on when remote is applied or does one/both have a delay before receiving voltage? This amp has two Switched B+, one for each pin 13 and 15 (as they are not tied together). Post #10 shows drawn schematic based on this amp.
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They both immediately start up at 14v once remote is attached, then pin 13 drops to 4v after 1.5 seconds, Pin 13 B+SW has the cap added (factory revision) that other amps without the revision don’t have it. It’s a 10uf 50v.
Is there a 4 second delay for either?
I'm looking for something that corresponds to the 4 second delay.
I'm looking for something that corresponds to the 4 second delay.
Blue trace is pin 15, yellow is 13 and purple is gate resistor. It’s now powering up at 1.8sec, I haven’t done anything to it.
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From your diagram, pin 15 should go high immediately when remote is applied and remain there. Is remote or B+ dropping in voltage?
My small 10a power supply voltage does drop thats the dip that you see right after the gate square wave forms. This also occurs in my larger 200a PS. But it is weird how now the amplifier is powering up after 1.2-1.5 seconds. Should I worry about that spike.
Here’s a better pic of the waveform. It’s exactly 1.8sec before before square output for gate resistor is stable. I think that would be normal, but what would cause that spike.
Here’s a better pic of the waveform. It’s exactly 1.8sec before before square output for gate resistor is stable. I think that would be normal, but what would cause that spike.
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At just about 7.5 horizontal divisions? I don't think so. I think it's just the regulator starting and overshooting (rail voltage) a bit. It settles down. That 13v will likely cover a wide range of voltages when playing music, especially at high power.
