Gang: I need some advise please. I'm trying to finish my KPA100 but I can't seem to get beyond voltage tests on page 46 of the manual.
I should be getting 90 to 150 V's at the junction of C77 & R11 but only getting 47 volts. I should be getting -5 to -25 V's at pin 8 of U4 BUT I'm only seeing -4.1. I did some research in the archives and came up with a few ideas. Checked D1 - D8 and T3 pads. All diodes pass continuity test and T3 seems fine and shows zero resistance between pads. Checking the schematics prompted me to lift the anode of D7 to remove U4. In doing this, the voltage at the junction of R11 came up into spec and shows 150 V's. This means that U4 is drawing the circuit down. SO, I sent Elecraft an e-mail and Gary sent me a new MAX1406. Figured I would install it and all would be good. NOT ! After installing the new U4, I rechecked voltage at R11 and found it is still just 47 V's. I've double checked orientation of U4, and it's fine. I was very careful to observe anti static procedures when installing the new chip. SO, I'm confused and not sure where to go from here. Any advise would be greatly appreciated. Thanks & 72: Jerry N0JRN ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
