Dave, please taunt Brymen to up their rotary switch tech instead of this "good enough" philosophy
Ahhh very nice. The transparent plastic appears to be needed for the jack-detect, IR opto-sensor passes through two jacks if you look carefully.
The supercaps are discontinued and soon to be unobtainium. I believe it's the same supercap used in Fluke 189, 287, 289 - but not sure.
07/2023 Elna is phasing out making coin supercaps, they are NRND but some production and stock available.
Elna 0.2F 3.3V DSK-3R3H204T614-H2L new p/n is RSCSK2043R3D01004T. Mouser 555-DSK3R3H204T614H2
Elna 0.33F 3.3V DSK-3R3H334T-HL new p/n is RSCSK3343R3D02008T. Mouser 555-DSK-3R3H334T-HL (thicker 2.1mm vs 1.4mm- fits)
Dave, please taunt Brymen to up their rotary switch tech instead of this "good enough" philosophy
The additional application processor with all the RAM really looks like huge overkill for such a multimeter. Almost makes no sense.
The additional application processor with all the RAM really looks like huge overkill for such a multimeter. Almost makes no sense.
Maybe they had used it in some other product?
Works well enough from a low power point of view.
Well, no doubt it's perfectly usable and a nice product, but they claim a 100h min battery life, which is not horrible, but so-so. Sure could get significantly lower consumption with a less complex overall system by migrating what's done by the MSP430 in a recent, low-power 32-bit MCU and implement all the UI on it as well. You get the idea. Simpler BOM, simpler system, cheaper, much lower power.
I think Panasonic was used but they discontinued their line up first, leaving Elna. I wonder what the power drain is, if a coin cell works.
Well, no doubt it's perfectly usable and a nice product, but they claim a 100h min battery life, which is not horrible, but so-so. Sure could get significantly lower consumption with a less complex overall system by migrating what's done by the MSP430 in a recent, low-power 32-bit MCU and implement all the UI on it as well. You get the idea. Simpler BOM, simpler system, cheaper, much lower power.
I still like my Fluke 37 and 77 series. 1000Hr life out of a carbon zinc battery. I would bet that a Lithium Iron battery like the Eveready Ultimate Lithium 9V would go a couple
of thousand hours or more.
You're looking at an almost 2 decade old design for the meter and a bunch of obsolete chips. They've respun the board for the current versions and I have not seen at teardown on a new 287/289.
How do you know they re-spun the design?
Well, no doubt it's perfectly usable and a nice product, but they claim a 100h min battery life, which is not horrible, but so-so. Sure could get significantly lower consumption with a less complex overall system by migrating what's done by the MSP430 in a recent, low-power 32-bit MCU and implement all the UI on it as well. You get the idea. Simpler BOM, simpler system, cheaper, much lower power.
You're looking at an almost 2 decade old design for the meter and a bunch of obsolete chips. They've respun the board for the current versions and I have not seen at teardown on a new 287/289. I'd be curious, but not curious enough to peel the calibration sticker off of mine and take it apart.
[...] Dave, please taunt Brymen to up their rotary switch tech instead of this "good enough" philosophy
What's their problem?
Didn't they perform fairly well in Jow Smiths switch testing?
But the most likely is that they haven't changed much, at least regarding the part I was talking about. What bunch of "obsolete chips" have you identified?
Does anyone have the schematic for fluke 287 and also for 179 please?