|Re: HP-65 sensor chip failure|
Message #15 Posted by aj04062 on 16 Aug 2010, 10:37 p.m.,
in response to message #14 by Ignazio Cara (Italy)
Well through continued help from Ignazio, I am slowly trying to find the fault.
I have connections between the motor control board and the Sense Amplifier Chip. It seemed I had found a fault when I discovered high resistance from RA connector to the RA pin on the IC.
Well, I jumped the trace (the motor control board has seen severe battery acid) and it STILL doesn't work.
I'm Stumped. I don't have a background in electronics so this question may be dumb, but I can't check the caps & resistors while soldered in, correct?
I also can't seem to be able to correct the break in the RA trace without desoldering the IC from the board. Is this advisible?
One thing I noticed playing around with the head is that it is slightly loose. If I push it in a little, the card will not go through and jambs up. If I wiggle it out, it allows the card to pass.
More suggestions are welcome, let me know if anyone has spare parts to buy!