Datron 1062/72 SoCal Calibration? - Page 1
Forum section: electronics / general

author: maginnovision
author_rank: Super Contributor
timestamp: March 14, 2019, 11:59:20 pm
content: I've emailed pretty much ever cal lab I could find around here and only 1 had said they may be able to calibrate these(and they'd have to go to arizona). Does anyone know of a good cal lab in southern california around burbank/san fernando valley? I really don't want to pay the cost of shipping and risk them being damaged. I'm also finding it hard to understand that even labs that list these meters say they can't calibrate them. I can do the basic DC cal, don't have the equipment to do AC and haven't checked ohms. Also don't have anything decent enough to cal independent ranges so doing it at home is out of the question.

author: maginnovision
author_rank: Super Contributor
timestamp: March 15, 2019, 07:00:38 pm
content: Since it seem unlikely anyone local can calibrate these, and they all guarantee there is a high chance they'd not be able to if I ship them out, what would be the cheapest acv and dcv calibrators? I can compare against my Prema if I need to due to specs being poor.

author: DC1MC
author_rank: Super Contributor
timestamp: March 15, 2019, 08:13:23 pm
content: I've reached this stage, being in DE everything it's a x3 more expensive, but hopefully in US you'll get some useful calibrator for only 3 finger, not an arm and a leg.Cheers,DC1MC

author: Johnny10
author_rank: Frequent Contributor
timestamp: March 15, 2019, 09:14:22 pm
content: What would make this a difficult CAL?

author: DC1MC
author_rank: Super Contributor
timestamp: March 15, 2019, 09:18:12 pm
content: Nobody has the expertise anymore, the CAL it's not particularly difficult, but it's not worth to train the monkeys for it, 2few customers.

author: maginnovision
author_rank: Super Contributor
timestamp: March 15, 2019, 09:27:31 pm
content: Yeah, the Cal isn't difficult but it does require potentially soldering or cutting some links. Oh my. I'm sort of shocked I thought I'd get the quotes, pick the one I liked most, and get it done. I'm almost done replacing all the caps(alu-electro, tants, and 250/400V film which looked rough and bubbly), replaced the locks, and bridge rectifiers come soon(they weren't looking great either). Then Cal needs done. I went through a bit of the 1072 DC but I needed to change a resistor and kids were asleep. For me the DC alone is fine but one of these I'm giving to my dad and I'd like to calibrate it for him.

author: Johnny10
author_rank: Frequent Contributor
timestamp: March 15, 2019, 09:32:35 pm
content: The ones I have repaired are fairly accurate.But it might be handy to do the 7 1/2 and use it to Cal the 1062.

author: maginnovision
author_rank: Super Contributor
timestamp: March 15, 2019, 09:42:53 pm
content: Quote from: Johnny10 on March 15, 2019, 09:32:35 pmOne of my 1062's tracks my calibrated 7.5 digit meter pretty well(few 10's of uV) the other one and the 1072 are not as close. This 1072 was in bad shape internally. Someone had taken both the current board and the AC boards out. They also pulled some of the chips from the analog board. To do basic AC cal requires high voltage 25khz AC which I definitely don't have.

author: Johnny10
author_rank: Frequent Contributor
timestamp: March 15, 2019, 09:52:12 pm
content: Sorry, I meant have the 7 1/2 Professionally Calibrated and then use that to calibrate the 6 1/2.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 15, 2019, 10:07:24 pm
content: If it is just the 25 kHz high voltage signal, one may just accept that particular part of the AC function as not really calibrated.The rather complicated cal procedure might well be the reason not to get this offered from the cal labs. Even if so the price might be quite high - possibly exceeding the price of a comparable meter. The normal cal at a professional lab would be just a check if the ranges - adjustments might be extra.With a 7.5 meter available one might do the calibration at home. For several such meters it might be worth getting used to the procedure.

author: maginnovision
author_rank: Super Contributor
timestamp: March 20, 2019, 08:19:16 am
content: I have a question directly related to this so didn't want to create a new topic. The final stage of calibrating these is setting the software calibration constants. I don't currently have the tools to generate all these signals, although an AC calibrator is on the way. I was able to fix DCV at .1V, 1V and 10V by using a power supply, some resistors I could heat and cool and a calibrated meter. That let me measure current with a shunt with good accuracy, 1V power rails which set clock speed, and a the generally useable 10V range but that's it. If you had to choose would you use poorly calibrated meters(assuming the last two cal companies I can find say they can't do it) or buy a Datron 4000A DC calibrator with Ohms(Or some other DC calibrator and necessary resistance standards)? The absolute accuracy of such an item wouldn't be great but I could at least get an idea by checking with a calibrated meter and have a rough idea of the uncertainty. Or who knows, maybe I could find someone to calibrate the calibrator.Update: Tek says 200/ea for 1062, 620 for 1072. Waiting on one more quote.

author: maginnovision
author_rank: Super Contributor
timestamp: March 21, 2019, 05:55:08 am
content: Ok, nobody tried to dissuade me so I bought a 4000A with option 20. It's listed as used so with any luck I can check it's pretty close and calibrate the meters before the 4000A dies on me.

author: DC1MC
author_rank: Super Contributor
timestamp: March 21, 2019, 06:18:15 am
content: Quote from: maginnovision on March 21, 2019, 05:55:08 amThis is the path I wanted to follow, but all of the EU calibrators are damn expensive, maybe we'll do the German meeting in May and a kind soul will carry a calibrator with. My freshly recapped 1082 cries for calibration.DC1MC

author: maginnovision
author_rank: Super Contributor
timestamp: March 21, 2019, 06:32:55 am
content: Quote from: DC1MC on March 21, 2019, 06:18:15 amI actually hadn't really considered it until I bought an AC standard to get that side calibrated... Which I need to fix without schematics(optimation Inc AC-110). I already feel like I have too much gear but if this is relatively close It'll be worth it. If it needs Cal because it's too far out I'm going to regret the whole thing, haha.

author: DC1MC
author_rank: Super Contributor
timestamp: March 21, 2019, 06:58:06 am
content: Quote from: maginnovision on March 21, 2019, 06:32:55 amI didn't see too many working, but uncalibrated, calibrators collecting dust on fleabay, so if you do carefully do the grunt work, replace caps and put power supplies to specifications, do the board contacts cleaning, same with the switches and in the end the device works perfectly except that in some range is 0.02% out of calibration, put it back to sale and it will at least bring you a profit.Good luck,DC1MC

author: maginnovision
author_rank: Super Contributor
timestamp: March 21, 2019, 07:13:54 am
content: Quote from: DC1MC on March 21, 2019, 06:58:06 amThat is actually sort of where one of my problems started. I had the 3 datrons but one had good cal. After replacing the caps even the good cal meter had no cal left... Oops, forgot about the grounded soldering iron tip. I should have it in my hands after the weekend so I'll see what it needs and make sure I don't make the same mistake again.

author: DC1MC
author_rank: Super Contributor
timestamp: March 21, 2019, 07:23:59 am
content: What I wanted to say is that there are a few calibrators collecting dust on *bay because there are sold with a sale pitch like: "sold as is, I'm a long term used equipment seller, but I can't test it and don't know anything about the unit, it may even be empty inside, and if not I will remove all valuable boards before shipping..." as opposed with "this unit is tested working but it needs calibration...".To reach there you first need to work a bit on your workbench (cleanliness, antistatic mat, basic EDD protection) and work-flow, the 10xx series have a quite robust calibration RAM and it's difficult to reset it, except for making a direct short-circuit to the back-up battery, or, of course, activating the calibration switch on the back and inputing strange values).So first measure and ask 10 times and solder once.Also the calibrators are DEADLYbeasts, they have really high and deadly voltages inside, be very careful !!!Good luck with your calibration adventure,DC1MC

author: maginnovision
author_rank: Super Contributor
timestamp: March 21, 2019, 08:04:27 am
content: I've worked with dangerous electrics before at home and work. Both work areas are very clean, properly grounded ESD mats, lots of light and space. All the tools and skills I need as well. The AC calibrator was sold as working but 100/1000V no output. Could mean it's trash, could be bad switches, who knows. The Datron has 60 Day return window, 14-day guarantee. If I work on the circuit containing Cal RAM I'll just have to use a different iron or remove the ground connection for the tip. I downloaded what was available from KO4BB for the 4000A so I'll probably look at that stuff some this weekend in preparation. If only I had bothered to look at schematics for the meters before I fixed and re-capped them.

author: maginnovision
author_rank: Super Contributor
timestamp: March 25, 2019, 07:42:04 pm
content: Well the 4000A showed up and current and volt ranges are within a couple ppm at the worst compared to the Prema that was calibrated in November. Needs to be cleaned up and checked out on the inside but seems good so far.

author: DC1MC
author_rank: Super Contributor
timestamp: March 25, 2019, 07:59:44 pm
content: Quote from: maginnovision on March 25, 2019, 07:42:04 pmNow tell us that it was 357$, shipping included, to cry in this ugly rain.Cheers and 'grats for you first calibrator,DC1MC

author: maginnovision
author_rank: Super Contributor
timestamp: March 25, 2019, 08:36:42 pm
content: Quote from: DC1MC on March 25, 2019, 07:59:44 pmHaha, no such luck. $1600 USD with shipping. It seems in good shape though, just wish the full manuals were available. Only being off 2mV at 1000V is pretty good too. Maybe it'd be better with full 4 hour warm up. I only had it running an hour.

author: DC1MC
author_rank: Super Contributor
timestamp: March 25, 2019, 08:45:22 pm
content: You can supplement it with a(nother) nice Fluke 5200A for AC ranges, (btw, VB means the seller is open to negotiations), it's right in my backyard and I really have to restrain myself to not get it:https://www.ebay-kleinanzeigen.de/s-anzeige/fluke-ac-calibrator-5200a-mit-ieee-488/1069367962-168-4501Cheers,DC1MC

author: maginnovision
author_rank: Super Contributor
timestamp: March 25, 2019, 09:02:28 pm
content: Quote from: DC1MC on March 25, 2019, 08:45:22 pmWell I've got an optimation Inc ac110 on the way and it seems like an early version of those. Either the power amp is dead or missing, or some electrical issue(wiring). I nearly bought a 5200 but decided I should wait to check on the other one I already bought first.

author: Johnny10
author_rank: Frequent Contributor
timestamp: March 26, 2019, 12:11:01 am
content: Whats going on ?Everyone is getting Datron 4000 units.Just a year ago nobody wanted them. They were selling for less than $500.Now ?

author: DC1MC
author_rank: Super Contributor
timestamp: March 26, 2019, 06:15:51 am
content: Quote from: Johnny10 on March 26, 2019, 12:11:01 amNow that the generation change has happened, the chance of getting a reasonable good calibrator decreased dramatically, just the really bad, forgotten and very few units belonging to deceased volt-nuts are available.Well, to be 100% honest, in EU there were never affordable DATRONS in the range of hundreds EUR, the fun part is that there are some from Eastern Europe (the last countries who replaced their calibration infrastructure) being sold, of course at 1-2 good used cars prices and up.Cheers,DC1MC