121GW oddity

[bashie]

I recently got my 121GW and while tinkering today I noticed something interesting:

When I tried to measure an 220K SMD resistor (marked 224), the meter read 149.xxK. I tried multiple times, and if the 121GW was in the 500K range it would read ~150kOhms, but it read 0.219 MOhms correctly if set to the 5M range.

My UNI-T meter read the resistance correctly in both the 600K and the 6M range.

[bashie]

I changed the batteries to 4 L91s yesterday. I drained them a bit to get the voltages lower, to ~1.63V, similar to the OCV of a fresh alkaline. The meter reported 6.4V.

When I switched back to alkalines it now reads ~215k in the 500K range 

It now reads 215k even with lithiums. What's going on 

Update: with a fresh pack of L91s it reads 150k on a 224 and 216k on another 224. Why though

[bashie]

from the manual:

> Lithium batteries have a higher voltage and may cause the device to malfunction.

Are there any detailed explanations about this?

[bashie]

It now reads ~149.7 and ~219 in 500k and 5m ranges respectively with 4 fresh alkalines 

@Dave ?

[EEVblog]

The extra voltage from lithiums will not cause an accuracy problem. That's a red herring.
Sorry, I know it's basic but I have to ask, you aren't touching the probes with your fingers are you?
This fault is very odd.

[bashie]

No, definitely not. When I keep the probes in place (not touching) when it shows 150K, I can switch into the 5M range and it will show ~220K. Weird

[Chalcogenide]

You are not measuring the resistance value while in circuit, right?

[armandine2]

Try regular THT resistors, first thing I'd have done after the weird SMD readings .

[EEVblog]

You are not measuring the resistance value while in circuit, right?

That was my next question.