If you're wondering: from my testing so far, a shorting lead or shorted set of leads measures ~0.1400-0.1800Ω on this meter; so far, I haven't figured out how the "auto-zero" is supposed to work. I really need to read the manual rather than just skimming it like 6 times. ![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
Well, RTFM is a useful last resort, but that reading sounds about right and in this case I would simply use 4 bits of wire ![Smiley :)](https://www.eevblog.com/forum/Smileys/default/smiley.gif)
LOL... I'm totally snurching that.
While I know I AM resourceful enough to build a pair of "semi-kelvin" probes for this thing, that seems a bit convoluted just to get it to come close to zero. I figured the fact I couldn't find some equivalent of Δ or "zeroing" was simple user error. One of the grails I was seeking in the purchase of this unit was the 4-decimal resolution for locating shorts in a PCB.
Ah, that's a chance to get a new class of test equipment, e.g. a Hytrak 100D. That is designed to measure low resistances (one range is up to 0.2
). You don't even need to look at the display, since it emulates a mandrake by screaming at you.
Glider pilots have a very similar instrument, the audio variometer, which allows you to know how fast you are going up/down while still keeping an eye on those other aircraft which are (hopefully) a few hundred feet away.
Yeah, I made a ShortSqweek back in the day; which I believe the Hytrak is a direct descendant of, so no stranger to that type of device. I was just looking for something slightly less disaster-prone.
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/wink.gif)
@mnem I think that the Auto Zero on the 3478A only really works when in V=volts mode by RTM it suggests that each time the probes are open circuit, the meter takes a reading and then subtracts that reading from the reading obtained when the probes are connected to a voltage source.
If you need to get to a zero for resistance readings then you will either need a meter as bd suggested which has a ohms adjust control such as a HP3466A or a Fluke 8012A both of which have the manual adjust pot to zero the ohms reading or a meter such as the Brymen 867 which the delta key.
Hmmm... I can turn AZ On/Off in Ω mode, so not sure what it's supposed to do for me there. That's why I figured I needed to RTFM and figure it out.
I guess my point is... the cheapest POS $3 analog meter from 50 years ago had zeroing/lead comp. It's kindof essential to the basic function of the device; why the eff would I NOT expect ANY ohmmeter I buy to have some equivalent? Should I REALLY expect to have to recalibrate every time I need to use a different probe or change the leads?
Who was the brainchild who decided THIS MODEL didn't need it? Here, let's make a car without any way of fucking steering it while we're doing "Darwin Award-Worthy" engineering decisions...
![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
mnem
But wait, there's more...