Thanks for all the replies on my 5500 rotor problem! I had some time tonite to work on it and here's what I got. On both a1 a3, and e1 e3 pairs I'm reading only 1.0 volts. Between a2 a3 , and e2 e3 pairs I see only .5 volts at half range, IE an elevation of 90 degrees = a reading of .5 volts. I'm going to order a new Q2 UA7806C and this should do it. Only question I have is why Q2 failed to only output 1 volt, don't they usually fail and output 0 volts? I'm thinking it might be something else in the circuit feeding power to Q2. If so I will work this further when I actually take the rotor box apart with the new Q2 in hand. One other thing, I wish I can find all my components' I boxed up when I moved. I bet I have 10 of these in stock :) Thanks again for all the help guys, the electronic copy of the manual was a big help as I can't find my copy....

73 Jeff kb2m

I'm having a problem with my 5500 after a thunderstorm. What is

happening is that the rotor works manually, but doesn't display az and

el

information

on the control box. Also when I try to use computer control it goes

all

the

way to stop in both azimuth and elevation. I'm thinking this might be

in

the

control box, as both az and el are doing the same thing, the control

box being the single point of failure. Did anyone ever have this

problem? How can I diagnosis what chip might be at fault without a

schematic. I vaguely remember having this same problem after a close

lightning strike with my prior az el Yaesu box about 14 years ago but

don't remember what chip I swapped out, or how I determined which one

was at fault. This getting old thing really sucks. Any help would be

appreciated.

73 Jeff kb2m