I'm not sure anymore if I mentioned my aquisition of a TekMeter THM560. Well, if I did not, it was due to the disappointment that came up after I discovered
1. that there is a more capable THM565
2. that I am lacking the RS-232 adaptor
Both are corrected with the aquisition of a THM565 complete with RS-232 adaptor and original TEK carrying bag. Although it is lacking the battery case, which is a alternative fit in place of the RS-232 adaptor (which is also the external power adaptor). But I have a battery case from the 560.
When I switched it on and activated the backlight, I immediately was convinced that this was a good idea, because it is far easier to read than the THM560, which is lacking this feature.
Other differences are the number of memories for waveforms/line faults/setups/screenshots, a real time clock and the 'motor trigger function', which gives a stable display with PWM drives.
Tektronix has committed a uncharacteristic error in their documentation for this meter. I tried to use the THM560 at work and it behaved erratic. in one position I got a reading, in another not. Also it tried to tell me that the channel, which I was using, was not connected. In the troubleshooting section not an applicable hint. Only when you read the specification table really carefully, you encounter the sentence: Use probes incorporating 9 leaf-spring contacts only.
This explains why not any shrouded banana plug will work with this meter. Correctly, it should have read 'at least 9', because more are ok. Less might work, but not in all positions, because the jack contacts are segmented to detect presence of a plug (and maybe other functions).
Anyway, I like it. From both meters together, the probe lead kit approaches original volume and the supply options are sufficient. It takes 6 AA batteries in the battery case, so I can do without the rechargeable battery pack. With the serial adaptor, a nice and sturdy tilt stand is included which makes it much nicer to use on the bench.
Here it is, without the accessories which are still with the 560 at my workplace.
Here is how I found out, that it does have the RS-232 interface, which wasn't advertised.
Measuring a low-level AC voltage from the adjustable AC output of the Zentro 7941 power supply.
Measuring a 6.6kHz triangle voltage from a function generator:
And showing the same signal on the scope:
The autorange function of the scope is pretty good, it made a stable and usable display immediately. This one is a keeper, the THM560 will be sold or bartered away.
I am very much interested to compare it with the more versatile Fluke 867, when I get my hands on one. With those two and the Dodo (YEW Model 2441) the multimeter count reached 51. Should I be afraid? Lucky that I will get rid of the THM560 - then I can feel again that I do not belong to the crazy sort of people which own more than 50 multimeters.