Hi,
First, thanks for posting the meter faces for the different meters. It's interesting to look at these pics and it explains something about what is being measured with the different meters.
Ron:
With the meter face you posted we can see that the internal resistance is just a tiny tiny bit over 6 ohms, but i would call it 6 ohms until we can get a measurement of that resistance, and they may have tried to include some other series resistance in with that. But for now, 1.5 volts divided by 6 ohms of course equals 250ma, and with a small drop in voltage that could easily drop to 240ma which is what you measured. 0.240 times 6 gives us 1.44 volts and that is not unreasonable for the 1.5v battery loading.
Due to the schematic that was posted which showed 11.5 ohms we can see that the meters were made a little differently for the two "versions". So that explains a lot about your measurement vs what we found elsewhere. Thanks for posting that pic, and it was certainly a very nice and clear picture so we can examine all the details.
About the "time" factor that has been talked about, that's the response time of the meter. Most digital meters are very poor when it comes to this so that's when an analog meter is usually recommended. A digital meter could take a full second to respond, while the tiny mass and tiny friction in a typical analog meter means it only takes milliseconds for it to rotate.
For example, measuring the voltage of a power supply or line voltage with little load, then suddenly applying a large load and then suddenly removing that large load. The digital meter might not even budge a bit from it's reading of say 120.00 volts because it just takes too much time to make the measurement, but the analog meter would dip down just a little bit (maybe 10 percent) to show that something changed fast. So we would not see anything on the digital but on the analog we would see that something did in fact happen, even though we could not get a super accurate measurement. So analog meters are sometimes favored over digital when there may be fast transients that we dont need to measure accurately but we still want to know that they are there.
That meter is pretty awesome as we can see the Ohms scale down near 1 Ohm is graduated into tenths (0.1 Ohms) which is pretty good for a general purpose analog meter. If we are careful in reading we might even be able to distinguish between 0.9 Ohms and 0.95 Ohms for example.
Billy:
Your manager is recommending things that are mostly based on fact, but unfortunately this last one about the current measuring capabilities of the different meters is not exactly true. Different digital meters can measure different max current levels. I have meters that can only go up to 200ma, but others that can do 10 amps, and another that can do 20 amps. You can also add a current shunt to go up to 200 amps but that's another piece of test equipment we'd have to discuss.
Rumpfy:
I think what you are talking about is to estimate the diode curve using the Ohms scale alone combined with the DC scale. This might work but you have to know the internal battery voltage too, and that can vary a little so you have to be careful. To get the reversed scale, just subtract the reading from the max of that scale...so if you read "4v" on the "10v" scale just subtract 10-4=6 so that would be 60 percent of the voltage.