Author Topic: "Analog" DMM?  (Read 1111 times)

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Offline Johnboy

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"Analog" DMM?
« on: March 29, 2019, 04:50:50 pm »
I've toyed with pulling the trigger on one of these for nulls (none of my meters have a bar). After glancing at the unusual specs claimed for this thing, I suspect the movement is IC-driven. Anybody got one to confirm?

Of course, I forgot to specify, sorry.

https://kaito.us/tp7244.html
« Last Edit: March 29, 2019, 05:03:48 pm by Johnboy »
 

Offline rsjsouza

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Re: "Analog" DMM?
« Reply #1 on: March 29, 2019, 05:49:28 pm »
I wouldn't bet the movement is driven by a D/A converter tied to an IC.

Which specs do you find unusual? Our 1960's ICE Supertester 680R had a 50µA movement and included all these functions plus frequency meter. 
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Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Offline Kleinstein

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Re: "Analog" DMM?
« Reply #2 on: March 29, 2019, 06:04:42 pm »
The meter looks rater conventional, including the nonlinear ohms scale. So I don't see a reason to have something digital included.
There is also the option to just use an amplifier - usually a pair of JFETs at the time.

I one though about a slightly digital movement with a stepper motor - but this was for large size. In cars there are sometimes such movements, that stop when power is off.
 

Online duak

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Re: "Analog" DMM?
« Reply #3 on: March 29, 2019, 06:29:37 pm »
It's hard to say for sure, but I think I see a standard D'Arsonval movement behind the prism around the zero adjust setting.  None of the specs on the meter look out of place for an analog instrument.  I have both analog and digital meters on my bench.  The only things I miss on the analog meters is autopolarity and autoranging.
 

Offline rstofer

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Re: "Analog" DMM?
« Reply #4 on: March 29, 2019, 06:57:23 pm »
The meter shows 20k Ohms/Volt as the input impedance on the DCV 0.1-50V scales and that is usually taken as full scale volts.  50V full scale would have 1 MOhm input impedance.

I think this is an analog meter.  I like it!

ETA:

I chased this down and it is indeed an analog meter.  I like analog meters so I bought one from Amazon.  I also chased down the Resistance Zero Adjust.  There is a knob <somewhere> as there is on every other analog meter.
« Last Edit: March 29, 2019, 09:17:26 pm by rstofer »
 

Offline mqsaharan

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Re: "Analog" DMM?
« Reply #5 on: March 31, 2019, 08:18:09 pm »
It's hard to say for sure, but I think I see a standard D'Arsonval movement behind the prism around the zero adjust setting.  None of the specs on the meter look out of place for an analog instrument.  I have both analog and digital meters on my bench.  The only things I miss on the analog meters is autopolarity and autoranging.

I know only of Sanwa. Some of their meters have autopolarity as an additional feature. For example EM7000 (have autopolarity on both V and mA), SH-88TR, YX-361TR. YX360TRF and SP21.

https://overseas.sanwa-meter.co.jp/items/index.php?id=8

There might be others from different companies, too.
 

Offline mark03

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Re: "Analog" DMM?
« Reply #6 on: April 01, 2019, 04:00:19 pm »
This reminds me of the advertisements that blanketed our local radio stations a number of years back, when MMDS (pay-TV over microwave link) was popular.  They said it was the new thing... "wireless cable"!  I honestly don't think they caught the irony :-DD
 

Offline Old Printer

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Re: "Analog" DMM?
« Reply #7 on: April 01, 2019, 05:09:30 pm »
Kind of like the analog scope adage that you should have if you can get one cheap...

I saw a Craigslist ad by a retiring electrician for a spotless Fluke 87V and an equally nice Simpson 7-M. The 87 was listed at a fair price, but the Simpson was $20. It was a 90 mile trip each way and my wife looked at me like I was nuts. When I got there I fully expected him to say it was a typo and should have been $120, which I had in the other pocket :)  It was that nice, case, probes with screw on alligator clips. I still pinch myself every time i open the case to use it. Wouldn't give up my DMMs, but I really like the way a good old analog meter reacts.



« Last Edit: April 01, 2019, 05:11:24 pm by Old Printer »
 
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Offline Kleinstein

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Re: "Analog" DMM?
« Reply #8 on: April 01, 2019, 05:59:24 pm »
I have once repaired analog meter with auto polarity - actually more like true RMS (with an AD RMS chip) and polarity indicators. So no switching between AC and DC, just the ranges. I don't remember the brand, but it was a little larger one for demonstration use (e.g. school).

There where a few old Siemens combined analog and digital multi-meters with both an analog movement and LCD with digital readout.
 


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