i have a heathkit automotive ignition oscilloscope that works very well, nice steady display. its 60 yrs old, tubes. uses 4 pin amphenol connector to the pick ups. for the lab scope, i bought a capacitive clamp on probe for the HV, and clamp on probe for a trigger signal. they are bnc. the problem is i can not get a steady , usable image on 3 different scopes. the trigger signal is steady, although the voltage peaks vary. the image from the HV pick up is jumpy, its not even on the horizontal. ive tried all sorts of trigger settings and levels. no change, and even auto trigger looks the same. id like to try the heathkit probes on the lab scope, and am working on making an interface, amphenol to bnc. i will do the same to use the new pick ups on the heathkit. i want to see what is what, maybe the new probes are just poorly made. that will take time to source the parts. in the mean time, maybe someone can see something im missing. this is a link to the trigger pick up :
this is the secondary pattern
thanks
this is the secondary pattern
thanks
