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First Benchtop Multimeter Advice

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itproman:
I need it for general stuff and ham radio use,so don't need it to be too precise.

So,first meter,preferably under $100 Canadian:

I see on Ebay:

BK Precision Dynascan Corp 2830 (radio museum puts it ca. 1988?)...

HP 3435A....(same source,ca. 1977?)

GW Instek GDM 8034 -can get 2 for $100,tested only for ACV and DCV,untested.Could be risky?

Fluke?




I know,as I see on this forum the HP 344401a is recommended.

In any event,is it worth blowing money on such old technology?



6PTsocket:

--- Quote from: itproman on February 05, 2019, 01:23:11 am ---I need it for general stuff and ham radio use,so don't need it to be too precise.

So,first meter,preferably under $100 Canadian:

I see on Ebay:

BK Precision Dynascan Corp 2830 (radio museum puts it ca. 1988?)...

HP 3435A....(same source,ca. 1977?)

GW Instek GDM 8034 -can get 2 for $100,tested only for ACV and DCV,untested.Could be risky?

Fluke?




I know,as I see on this forum the HP 344401a is recommended.

In any event,is it worth blowing money on such old technology?

--- End quote ---
If it doesn't have to be that accurate why not get a hand held instead of a bench meter. There is a lot to choose from for 100 bucks. Plenty of new hand helds will perform better than many an old bench top.

Sent from my SM-G900V using Tapatalk

0culus:

--- Quote from: itproman on February 05, 2019, 01:23:11 am ---I need it for general stuff and ham radio use,so don't need it to be too precise.

So,first meter,preferably under $100 Canadian:

I see on Ebay:

BK Precision Dynascan Corp 2830 (radio museum puts it ca. 1988?)...

HP 3435A....(same source,ca. 1977?)

GW Instek GDM 8034 -can get 2 for $100,tested only for ACV and DCV,untested.Could be risky?

Fluke?




I know,as I see on this forum the HP 344401a is recommended.

In any event,is it worth blowing money on such old technology?

--- End quote ---

I bought a ~1977 vintage HP 3455A for $150 last year. After fixing a contact issue in the main ribbon cable that connects the digital board to the display, it runs like a champ. What's more, it agrees with newer meters exactly (I am trying to avoid being a voltnut for my wallet's sake!) No reason to avoid older stuff. HOWEVER, keep in mind that older ones are bigger, heavier, and there's more likely to be age related problems (such as aforementioned contact issue, but also bad electrolytic caps).

I also have a Fluke 87-V. The 87 gets more use simply because it's easier to move. But it's nice to have multiple ways measure when you're testing or building things, so I plan to get at least one more bench meter at some point.

Doctorandus_P:
Benchtop DMM's are excellent candidates for home brew solutions.
With a power cord low power is not an issue.
You can use big fat 7 or 16 -segment displays, or a TFT display.
24 bit ADC's (With about 20 bit noise less resolution) are readily available.
Use some microcontroller to glue everything together.
Add some data output for logging to a PC, or uSD.
Such ADC's can often sample upto a few ksps. (With reduced resolution). This is very usefull for extremely fast autoranging. You can have a stable readout in less time than it takes for your eyes to move from your probe to the display.

You really do not need to spend more than about EUR 30 on components for such a meter.

For the rest, save up some budget to buy a high quality handheld DMM as a reference to calibrate your homebrew device, such as a Brymen in the near EUR200 range. From what I know these have very similar spec's and reliability than the over priced Flukes. Why would you want to use a parasitic flatworm for measurements anyway? At best it's just luck if that meter functions properly.

Skullcom has designed a simple mV meter with a decent ADC, (Open Source, Schematic and Source code on the 'net). but I would swap it with the ADS1220 with built-in reference voltage and PGA. But still a nice headstart to build a custom meter with the ranges and measurement functions which fit your personal situation. If you have the sourcecode it is for example trivial to add some linearisation functions for weird sensors.

Those modern ADC's are so good that it is well worth to put relatively expensive resistors (low drift / tempco) in such a meter, and spend some extra time cleaning the PCB.
Combine this with a few other relatively simple (but non trivial!) things and you have a very nice high speed 5 digit resolution meter and the biggest problem would be to calibrate it properly (Hence the EUR 200 Brymen).

The good part is that if you've gone through the trouble of designing a PCB and some software then building 4 or more meters becomes trivial and cheap. Having a few multimeters is always nice for measuring various voltages and currents simultaneously. If you have multiple meters, then they also do not all have to have all measurement ranges. Why would you want 5 meters that can all measure resistances and capacitors?

rdl:
When I was restarting in the hobby 15 years ago, I bought a rebadged Mastech M9803R from RSR Electronics (just don't like the name "Mastech" much). I just wanted someting that would sit on a shelf without flopping around and falling all over the place, and run off mains power for as long as I wanted without shutting off. It has never given me any problems.

If I was looking today, I might go for an HP 3468A, which is not as large as the other HP bench meters and can be found fairly cheap on ebay. It doesn't have a lighted display though, and that's a big negative to me.

Another alternative is one of those VC8145 meters you can find on ebay. I may buy one just because it would be an upgrade over what I have now, not that I need one.

https://www.ebay.com/sch/i.html?_nkw=VC8145

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