Okay I'm a little preplexed. Here is what I have right now. FETs are out. A1023s are out. Switching diodes are out. I measure from ground post to FET gate pads like before and my resistance is now way out. Outside four pads to ground = 0.497 M ohms. Inside four gate pads = 218.7 k ohms. I've drawn myself a small layout diagram and yet I don't see why the difference in resistances. Any thoughts before I solder everything back in?
Both of the resistors are 1k ohm resistors with a +/-5% tolerance. They measure 993 and 995 ohms respectively. I'm starting to draw a layout diagram of the components and hooking them up from the ground side on paper, I just don't see where the difference can be. I'm obviously missing something.
I'm back. Down with the flu this week. Here is what I have. I am perplexed. Fets are still removed. Two A1023 driver transistors still removed. Sitching diodes disconnected on one end. Measuring from ground to Pin 9 and 10 of 494 = 0.994 k ohms. Measuring from ground to FET gate pads. Outside two = 28.4 M ohms. Inside two = 14.6 M ohms. I have cleaned all residue, followed all tracks and still can't see where the excessive resistance is coming from between tracks. Where is the connection between these points and ground? I don't see it. From switching diodes to gate resistors, no resistance and no relation to ground. All resistors measure 99.4 ohms and end at gate pads. Still do not see connection to ground. Thoughts?
It would be interesting to know what's causing it but anything in the megaohm range is not going to be a problem. Reinstall all components except for the power supply FETs and measure the DC voltage at pins 9 and 10, the bases of the driver transistors, the emitters of the driver transistors and the gate pads of the power supply FETs. All corresponding points should read virtually the same voltage. The voltage at pins 9/10 and the gate pads should be approximately the same.
So far so good. The green power light is on, it is running on 12.6 volts and around 750mA draw. Pins 9 & 10 have 3.95 volts and no blown fuses as of yet. So we move on to the next step?
I have a Kenwood receiver and a set of MTX Audio 10" Jackhammer subs from my son's car. Can I hook this all up now and what do I need for a power supply. I have a Pyramid PS-32LAB 0-30v 0-5 Amp power supply. Should I use a car battery instead and do I have to hook up anyother speakers besides the subs?
I have a Kenwood receiver and a set of MTX Audio 10" Jackhammer subs from my son's car. Can I hook this all up now and what do I need for a power supply. I have a Pyramid PS-32LAB 0-30v 0-5 Amp power supply. Should I use a car battery instead and do I have to hook up anyother speakers besides the subs?
If there is no DC on the RCA jacks, the receiver should be safe. You'll have to monitor the amp while it's playing so you can shut it down if it fails again (applying excessive DC to the speaker terminals). Unless the woofer is rated for very low power, that's about the only thing that could harm it.
Hi Perry,
Just want to take a quick second and thank you for all your help. Soundstream is up banging away again and customer is going to be very happy to get it back. Ran it for over an hour with nothing heating up and no blown fuses or incidents. Thank you for all your help and I'll be back soon with a new project. The lessons on this one have inspired me to learn more. Good chat on the side as well.
Just want to take a quick second and thank you for all your help. Soundstream is up banging away again and customer is going to be very happy to get it back. Ran it for over an hour with nothing heating up and no blown fuses or incidents. Thank you for all your help and I'll be back soon with a new project. The lessons on this one have inspired me to learn more. Good chat on the side as well.
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