For the test leads, I’ve used 12 G silicone ultra flexible wire with good results. You can get it from BNGTECHGO on Amazon.
Does the capacitor test function work correctly on yours? I’ve been through about five of these units and none of them worked properly,. I kinda fixed one.
I am not sure if this will help, but there is a Merc-O-Tronic 98 complete manual in the “Inner Sanctum”. Look for it in the “Old Iron Library under manuals.
Tom I have had and have a number of Merc O tronics and the condenser test is usually the first to go I used to send them back for repair but the company is no more I think Mercury gave us [ I’m a mercury service only dealer} an address that was good 3 yrs ago but does not work now so A member of the club here in maine is into electronics and believes most of the problems are in the momentary switch red button . If you know some one who is willing to repair these and successful at it I would love the name and no. The last time I had one redone it was 250.00 and a bargan Lincoln
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