I have been looking for a DMM reference standard for several new and used DMMs I just acquired. Thus far it seems the most capable and affordable device I have come across is the DMMCheck Plus which seems to have been discontinued by VoltageStandard. As it seems there are quite a few people on the forum who have also recently acquired new gear I wanted to know if there was any interest in a DMMCheck Plus group buy. To be clear I have not run this idea by Doug Malone of VoltageStandard so I do not have any commitment on the production of these devices. I wanted to gauge the level of interest on the forum and if the numbers were high enough I though maybe he would consider a limited run. No idea on current pricing, timeline or any other details. Just floating the idea.
I had hoped to buy a DMMCheck Plus last week until I found they were discontinued.
I would be interested in joining a group buy for the DMMCheck Plus
I had hoped to buy a DMMCheck Plus last week until I found they were discontinued.
That's what I thought too.
LOL just posted about this in another thread. I have one, and love it, it's quite handy to have. I wonder why he discontinued it. Now all he seems to be selling are voltage standards.
sometimes they show up on ebay for around $ 100
I have one as well it it works really well.
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Sent earlier today.
"Mr. Malone,
I would like to direct your attention to a forum topic I created regarding your discontinued DMMCheck Plus device. I am currently gauging interest on the forum and while I have not received many responses to date the responses I have received have been very favorable. I obviously don't know what the threshold of economic feasibility is for the resurrection of this product line but I thought you should know some of us are at least having the conversation. Thank you for your time and efforts."
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
I would be interested in getting one as well.
I'll put my hand up for one.
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
TiN is one of our forum's metrology nuts, a good thing.....if you need 7+ digit accuracy.
5 units is plenty for a sanity check of your HH DMM.
A customer that I sold 15 Fluke 15B to got a DMMCheck to align them all perfectly for classroom use....you can't have students not all agreeing to the last digit on a 3 1/2 digit DMM.
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
Can't speak for TiN, but he might be referring to the experience made by Joe Geller, who also offered a fine voltage reference for hobbyists, but learned that it was not a viable business. He shared his experience here:
http://www.gellerlabs.com/about.htmlAt the high end the labs charge good money to stay afloat and the cheap AD584 references aren't really calibrated, at best compared to a mid-level DMM itself of questionable calibration. It's in the middle where it's apparently difficult.
It's a pity really. I'm proud owner of a DMMCheck, which as far as I can tell works as advertized. I missed out on Mr. Geller's reference, but you find quite a few quotes of satisfied customers.
Old link from browser but not for the Plus model.
http://www.voltagestandard.com/DMMCheck.htmlThe Plus has been mentioned recently in another thread:
IIRC it was ~$ 70, but its redeeming feature was it contained a # of standards; voltage, resistance and frequency....
Mr B will put us right on just what it had.
Yes it was about USD70 shipped.
It has:
10VDC
1mA
1K, 10K, 100K
The DMMCheck 'Plus' version had ACV, ACmA and frequency.
It was a bit more expensive and I chose the cheaper option at the time.
I also have one of the cheap USD20 units out of China that has DCV only, but switchable between 2.5, 5, 7.5 and 10.
It is very good for the price.
I am in, if he will make some more
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
Sure, mid-level references, which targeted for serious hobbyist with 5.5-6.5-digit DMM already require expensive and time consuming support framework, to meet the specification requirements.
It's easy to design and assembly bunch of boards with ref chip, and BOM cost is reasonably low. However backing up listed specifications even to meet 5.5-digit meter stability requirements with good confidence dictate need of having stable and validated DC standard such as 732A/B or similar, stable and properly cared reference meter, such as 3458A or similar. Now even if we assume that all this gear available and ready to use, we still need to maintain calibrations (which are 500+$ for DC standard, 1000+$USD for reference meter) annually. Then add scanning setup and long-term testing, as you need to be sure reference is stable and that test cannot be done in day or week. Automating setup and data processing is another effort required, to keep everything running.
So in the end you have hours and hours of work, cost of maintenance of expensive support equipment to build and sell little reference boards. Surely all that cost can be factored into the product price, but try to explain to Joe-doe why a PCB with 30$ BOM (anybody can google up AD584 price and few 5ppm/K resistors) costs over 100$ in the end? That also confirmed by
my own attempt to sell tested reference AT the BOM cost, with FREE testing, which took 4 months to get sold.
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
Sure, mid-level references, which targeted for serious hobbyist with 5.5-6.5-digit DMM already require expensive and time consuming support framework, to meet the specification requirements.
It's easy to design and assembly bunch of boards with ref chip, and BOM cost is reasonably low. However backing up listed specifications even to meet 5.5-digit meter stability requirements with good confidence dictate need of having stable and validated DC standard such as 732A/B or similar, stable and properly cared reference meter, such as 3458A or similar. Now even if we assume that all this gear available and ready to use, we still need to maintain calibrations (which are 500+$ for DC standard, 1000+$USD for reference meter) annually. Then add scanning setup and long-term testing, as you need to be sure reference is stable and that test cannot be done in day or week. Automating setup and data processing is another effort required, to keep everything running.
So in the end you have hours and hours of work, cost of maintenance of expensive support equipment to build and sell little reference boards. Surely all that cost can be factored into the product price, but try to explain to Joe-doe why a PCB with 30$ BOM (anybody can google up AD584 price and few 5ppm/K resistors) costs over 100$ in the end? That also confirmed by my own attempt to sell tested reference AT the BOM cost, with FREE testing, which took 4 months to get sold.
Yes. Accuracy costs money and there is no way around it. You can have a cheap reference or you can have an accurate reference but not both. On the other hand, I'm offering a free to use for a week or a couple of weeks calibrated reference which is good for 5.5 digit meters check (and possibly up to 6.5 digits but it only can be confirmed after some months of travelling and repeated measurements). I
need it to go around and be used, to gain some statistics and see if it can be improved for another build, however for over two weeks there are no requests and no apparent interest. I thought a regularly checked and calibrated reference with a known history and good accuracy, available for postage costs only to check meters and references for a hobbyist makes a good sense, but perhaps I was wrong?
Cheers
Alex
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
Sure, mid-level references, which targeted for serious hobbyist with 5.5-6.5-digit DMM already require expensive and time consuming support framework, to meet the specification requirements.
It's easy to design and assembly bunch of boards with ref chip, and BOM cost is reasonably low. However backing up listed specifications even to meet 5.5-digit meter stability requirements with good confidence dictate need of having stable and validated DC standard such as 732A/B or similar, stable and properly cared reference meter, such as 3458A or similar. Now even if we assume that all this gear available and ready to use, we still need to maintain calibrations (which are 500+$ for DC standard, 1000+$USD for reference meter) annually. Then add scanning setup and long-term testing, as you need to be sure reference is stable and that test cannot be done in day or week. Automating setup and data processing is another effort required, to keep everything running.
So in the end you have hours and hours of work, cost of maintenance of expensive support equipment to build and sell little reference boards. Surely all that cost can be factored into the product price, but try to explain to Joe-doe why a PCB with 30$ BOM (anybody can google up AD584 price and few 5ppm/K resistors) costs over 100$ in the end? That also confirmed by my own attempt to sell tested reference AT the BOM cost, with FREE testing, which took 4 months to get sold.
Thank you for the details. Being relatively new here I am not familiar with a lot of the history. Seems to be the same economic pattern I see in every market. Price trumps quality, performance and every other metric. While it make some sense in the consumer market I don't understand this logic in the technical market where the merits of a product justify the cost. Why then do we buy 8.5 digit meters when you could buy 10 5.5 digit meters with the same money? Rhetorical question I know.
On the other hand, I'm offering a free to use for a week or a couple of weeks calibrated reference which is good for 5.5 digit meters check (and possibly up to 6.5 digits but it only can be confirmed after some months of travelling and repeated measurements). I need it to go around and be used, to gain some statistics and see if it can be improved for another build, however for over two weeks there are no requests and no apparent interest. I thought a regularly checked and calibrated reference with a known history and good accuracy, available for postage costs only to check meters and references for a hobbyist makes a good sense, but perhaps I was wrong?
Well, I, for one, missed this. Perhaps others missed it too? You might try asking again and see if you get some/more traction.
I'm not sure if I can offer any usefully accurate measurements [current state of play chez Cerebus is one of poor traceability], but if your reference wants a little holiday in London I can offer it all the (well regulated) current it can eat and it can enjoy some friendly conversation with some LM399s. At least you might get to see what a round-trip does to it.
Mid-level references are uneconomical. Too much trouble to maintain the thing properly, with iceberg of hidden costs.
Could you please elaborate?
Sure, mid-level references, which targeted for serious hobbyist with 5.5-6.5-digit DMM already require expensive and time consuming support framework, to meet the specification requirements.
It's easy to design and assembly bunch of boards with ref chip, and BOM cost is reasonably low. However backing up listed specifications even to meet 5.5-digit meter stability requirements with good confidence dictate need of having stable and validated DC standard such as 732A/B or similar, stable and properly cared reference meter, such as 3458A or similar. Now even if we assume that all this gear available and ready to use, we still need to maintain calibrations (which are 500+$ for DC standard, 1000+$USD for reference meter) annually. Then add scanning setup and long-term testing, as you need to be sure reference is stable and that test cannot be done in day or week. Automating setup and data processing is another effort required, to keep everything running.
So in the end you have hours and hours of work, cost of maintenance of expensive support equipment to build and sell little reference boards. Surely all that cost can be factored into the product price, but try to explain to Joe-doe why a PCB with 30$ BOM (anybody can google up AD584 price and few 5ppm/K resistors) costs over 100$ in the end? That also confirmed by my own attempt to sell tested reference AT the BOM cost, with FREE testing, which took 4 months to get sold.
Yes. Accuracy costs money and there is no way around it. You can have a cheap reference or you can have an accurate reference but not both. On the other hand, I'm offering a free to use for a week or a couple of weeks calibrated reference which is good for 5.5 digit meters check (and possibly up to 6.5 digits but it only can be confirmed after some months of travelling and repeated measurements). I need it to go around and be used, to gain some statistics and see if it can be improved for another build, however for over two weeks there are no requests and no apparent interest. I thought a regularly checked and calibrated reference with a known history and good accuracy, available for postage costs only to check meters and references for a hobbyist makes a good sense, but perhaps I was wrong?
Cheers
Alex
This kind of thing is exactly what I asked the maker of voltagestandard.com about. He didn't answer my question, but I didn't ask it very well either. I wasn't interested in group buy; I was interested in making traveling voltage standards (the Pentaref model). So you would make a set of references, acquire a set of customers who pay some kind of either annual or one-time fee, and the voltage standards are programmed to suit each customer, checked out like library books, used for a few weeks, and then returned. Then they would be reprogrammed for different voltage values, and sent out again.
I actually need a voltage reference (I need specific voltages though, 190.000 mV, 1.90000 V, 19.0000V, 190.000V, and 1000.00V) to calibrate some Keithley 197s which are 220,000 count "5.5 digit" multimeters. I didn't know you were sending around a reference!
Sent earlier today.
"Mr. Malone,
I would like to direct your attention to a forum topic I created regarding your discontinued DMMCheck Plus device. I am currently gauging interest on the forum and while I have not received many responses to date the responses I have received have been very favorable. I obviously don't know what the threshold of economic feasibility is for the resurrection of this product line but I thought you should know some of us are at least having the conversation. Thank you for your time and efforts."
Any reply?
Unfortunately no. Strange because he replied to my initial inquiry as well as my follow up email where he gave his reasons for discontinuing the product.
This kind of thing is exactly what I asked the maker of voltagestandard.com about. He didn't answer my question, but I didn't ask it very well either. I wasn't interested in group buy; I was interested in making traveling voltage standards (the Pentaref model). So you would make a set of references, acquire a set of customers who pay some kind of either annual or one-time fee, and the voltage standards are programmed to suit each customer, checked out like library books, used for a few weeks, and then returned. Then they would be reprogrammed for different voltage values, and sent out again.
I actually need a voltage reference (I need specific voltages though, 190.000 mV, 1.90000 V, 19.0000V, 190.000V, and 1000.00V) to calibrate some Keithley 197s which are 220,000 count "5.5 digit" multimeters. I didn't know you were sending around a reference!
I actually really like this idea. It make complete sense. I am willing to buy a travel standard but admittedly it would just sit on a shelf for the vast majority of its life. A standard that is sent around would be peer reviewed, traceable and I would expect well maintained. I think there would have to be some type of payment and deposit system in place obviously. There has to be a way to distribute the enormous cost of calibration across interested individuals and still make it profitable for the standard builders.