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VTVM - misaligned, or I need to learn how to read?
#16

since you have it aligned now you'll find yourself using it more and more......

I find it alot easier to see the needle move than to see digits change on the fluke....plus i think it is more sensitive to very small changes in voltage...like when aligning a radio

as far as your switch..i dont know

all the ones I've ever had have a separate lead for AC/OHMS and DC
#17

I think I'd like to have a different one for AC/OHM and DC instead of having a switch that does so. It makes a huge thing about as big as the 10x probe on some scopes, not exactly useful.

I think I could use an old mono jack as a connector and make my own... what's the difference between the two? a capacitor?

-Mars
#18

It's a resistor. Usually 1 megohm. Check the schematic
#19

could I just measure it from my actual probe set?

I am really thinking about making at least two set of probes for it, the bulkiness of the original probe renders it annoying to use. They are a pair of huge alligator clips, I'd rather have actual probes, or at least small alligator clips.

-Mars
#20

You very well could make separate probes for it. My Dad has a later solid-state Heathkit VOM and I believe that it has separate probes for DC and AC/Ohms. You would just have to remember to use the correct probe but it might be easier to remember to switch probes than to switch the switch. Especially if you use two different colored probes.

Sean
WØKPX
#21

Or maybe I would make one that the switch is not ON the probe... it really is annoying because of how bulky it is.

-Mars
#22

There are lots of web-articles describing DYI probes with the 1 MegOhm resistor in the tip for the DC probe. I found a nice kit with good parts all ready-to-go in the Deluxe Heathkit VTVM Probe Kit – Complete kit for 3 Wire Meters V-4/5/6/7A from KK4HXJ through the e-Bay.  The seller is also friendly with advice. Very nice to get my dad's old IM-10 back on the road.
#23

Welcome to the Phorum! KC7HP
Icon_wave
#24

Marsupial

Boy he hasn't posted in a llllllooooonnnnnnnngggggggggg time!!!

Hi Hugh and welcome to the Phorum,
Good to have aboard. Nothing like a good hi z analog meter. These new fangled digital jobs are good for ohms but any voltage w/some rf content it plays with it's head. Years ago I used one to work on a tube type tv and it drove me crazy. Nothing was measuring properly w/it. Welll except for resistance.

de N3GTE

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!

Terry




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