Both lm3886 boards connect to the one supply . that is the factory setup and its works. however, I cannot drive the amps with any of my lab supplies. They all connect the same . One supply - 2 boards
The factory power supply is a standard DC output supply, 26v DC + - & groundSo what is "neg"?
A picture would help.
yes I have set the current to 2amps ,,3amps ,6amps 10amps and no go. I would like to think DC is DC. but not in this case.Test that PM amplifier with another capable PSU.
Have you current limited your PSU? What is the setting?
I get it ! finally . So the solution is to use " 2 lab power supplies" and jumper them accordingly to output +26 and -26 . I guess that is the reason for dual power supplies.The HP 6267B is a single lab supply. From the pictures in your ebay link, it is quite clear that the LM3886 module needs +26 V, ground and -26 v.
Your lab supply is only supplying + 26 V.
I don't know how to explain it clearer.
YES! At last!I get it ! finally . So the solution is to use " 2 lab power supplies" and jumper them accordingly to output +26 and -26 . I guess that is the reason for dual power supplies.
ya ya ya ! well anyhow I got it to work with two discrete lab power supplies thanks to Benta. Thank you Benta for being patient .Look at the pretty pictures in the post #22 link. The amplifier boards have three power input pins, V+, GND, V-. The power supply board has three power output pins, +V, GND, -V. As mentioned in posts #4 and #6 (!!!), a single output power supply will not operate these amplifier boards. All four of the power supplies listed in post #16 are single output supplies. One at a time, none of them will work. The supply in the link is a single device, but it is a dual supply. It has two power outputs, not one. The amplifier boards need two power inputs, not one. That is why they work with the intended supply. That is why they do not work with a single lab supply. Another 25 posts will not change this.
ak
right now i am earth grounded and it sounds great , however, I will take your advise and try floating them.YES! At last!
Just make certain that the outputs from the lab supplies are truly floating (they usually are, but earth connections can make trouble).
by Jake Hertz
by Jake Hertz
by Duane Benson