Hi Hank,


Thanks for the tips, got the line from 60 deg to 45 degrees by tweaking
another pot...

The correct angle for the LOW setting should be whatever gives you a
line that goes from the lower left corner to the upper right corner of
the screen.

I tested a 30 volt zener and got a good Z but just got as small blip on one
leg of the z on a 56 volt zener

That sounds correct. Nothing about the Huntron is absolute, only
relative.

I measured the voltage on the probes, 60 Hz, hi: 40.5 volts, med 20.4 volts,
and lo is 6.6 volt.

The actual voltages will be somewhat higher. The Huntron is a very high
impedance source.

Since these are rms, and peak to peak would be 2.8 higher,,
Does Huntron caution about testing any devices because of the voltage?

Huntron is very specific to say that the Tracker CANNOT harm any solid
state device, or other component. I would be worried about some of the
older Mosfets like the 3N128 which have no protection diodes built
in. But in a properly designed circuit, the circuit elements would
protect even a Mosfet.

With a short all 3 levels show a vertical line but with an open high and
medium present a horizontal line while low presents a 45 degree line. Do
you know the reason for this?

The early Huntron Trackers used parts that presented a fair amount of
series resistance to the measurement circuit. This series resistance
wasn't visible in the High and Med positions, but in the Low, it would
have made a diagonal line on short circuit. The folks at Huntron must
have felt that it was more important to make a short circuit always
appear as a vertical line than it was to make an open always appear as
a horizontal line, so they added circuitry that allowed them to rotate
the display in the LOW position to make a short appear as a vertical
line.

In later Huntrons, they figured out how to null out this impedance and
those units always have a short vertical, and an open horizontal.

-Chuck

hank
I posted a personal reply as well as to the groups as I figured others might
be interested.

I wish you wouldn't!

I check email a lot more often than newsgroups. I don't usually
notice that you have done this until after I have composed and sent
a response to your email. Then when I read the same question in the
newsgroup, and have to reply there as well. A lot of bother.

If you want the reply on the newsgroup, please don't send an email!