Hello all. New to this site but not radios. Been a ham since 98. Any ways, I was about to post a help thread on this old DX 88HL I have. The serial is 007987. When I got it, had the typical freq. counter,display noise when turned on. You could hear it in the transmit audio and outside the radio when on. This is the very early production EPT210010A board. Did a realignment of said board and couldn't get just right so I rebuilt it. ALL new low ESR caps, metal film resistors, replaced all ICs, all ceramic caps and got it tuned perfect. No more audible counter whine but was still in transmit audio. Fallowed counter ground wire and would ya know it, right to the mic gain pot on front of radio. Removed ground from pot, ran longer wire to rear of PC board ground with a 1N4001 diode and BINGO! No noise at all. Total cost for board rebuild was like $40 and my own time just for what may have been bad ground location...... But she is ready to rock for 20 more yrs. LOL Counter and clarifier is dead nuts with no warm up time so far. If anybody has a similar older unit, look at the blue wire or pc ground in the 3 wire plug on freq. counter module. It may just need moved with added diode to shut her up! 73's and remember, I'm pulling for ya!
