1) Purchased.
2) Plugged in leads that came with the meter.
Just for the record, were the leads you received made by Brymen or UEI ?.
At different times I believe both brands have been supplied with the 121GW and I'm pretty sure the UEI leads have a really long strain relief on the banana plug end. I received the Brymen leads with the BM-235 and have found them rather a tight fit in some other meters such as the Flukes.
Dave,
I'm not sure if this is an issue or not, so feel free to erase it.
Way back when you sent me the prototype meter, it included some really old firmware and you supplied me with what documents you had at the time. At that time the alignment procedure was not included in the user's manual. When I attempted to upgrade the firmware on this meter, the calibration was no longer valid. I think this was something you had posted about or covered in Amp hour. I made some transfer standards using my bench meter and realigned it. I took some notes about what I had done and called it good enough.
There is a member attempting to realign their meter and they ran into a problem.
https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2790680/#msg2790680
Looking at the various manuals that were made available that include the alignment procedure, it appears that they changed it. I suspect based on what this person has found and having gone through it myself, this is the reason the meter is no longer able to read down into the 100pF ish values.
Dave,
I'm not sure if this is an issue or not, so feel free to erase it.
Way back when you sent me the prototype meter, it included some really old firmware and you supplied me with what documents you had at the time. At that time the alignment procedure was not included in the user's manual. When I attempted to upgrade the firmware on this meter, the calibration was no longer valid. I think this was something you had posted about or covered in Amp hour. I made some transfer standards using my bench meter and realigned it. I took some notes about what I had done and called it good enough.
Anything related to the prototype meter I sent you should have no relevance to any production meter, this is why I specifically told you at the time not to test it or review it, it was just for shit'n'giggles to watch the magic smoke escape.QuoteThere is a member attempting to realign their meter and they ran into a problem.
https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2790680/#msg2790680
Looking at the various manuals that were made available that include the alignment procedure, it appears that they changed it. I suspect based on what this person has found and having gone through it myself, this is the reason the meter is no longer able to read down into the 100pF ish values.
I don't recall changes to the calibration procedure.
input jacks which were injected from the uncompletely-cleared mould probably resulting in for ABS mixed with any foreign materials so the injected jacks could be more easily broken.
2. Our input jacks were designed to be ideally matched with our test lead probe with 4.2 - 4.3 phi. However, Brymen's probe has 4.5 - 5.0 phi, which can give more mechanical stresses to our input jacks.
Thanks for the quick update Dave. I'll be sending an email to get a replacement jack assembly from you as I'm pretty sure that my SN is within the affected range, though it's a shame that you've got to go through this.
UPDATE:
The issue with the cracked input jacks is as several suspected, a molding issue.Quoteinput jacks which were injected from the uncompletely-cleared mould probably resulting in for ABS mixed with any foreign materials so the injected jacks could be more easily broken.
Units potentially affected are with serial numbers S/N 18087001 to 181008000
The sockets for these were manually inspected for this issue but it seems that some slipped passed the inspection and have resulted in cracking.
They also mention the Brymen leads are not ideal:Quote2. Our input jacks were designed to be ideally matched with our test lead probe with 4.2 - 4.3 phi. However, Brymen's probe has 4.5 - 5.0 phi, which can give more mechanical stresses to our input jacks.
"Phi" means diameter of the banana plug.
I'm not sure about their measurements because I measured the Brymen at 4.3mm or a smidge over. The UEi ones are spot on 4mm and not the lantern type ones the Brymen use.
They aren't saying don't use the Brymen leads, just that could be a contributing factor in this case. Welectron have been supplying Brymen leads.
My new stock of meters will all come with UEi leads.
They will be sending me a bunch of replacement jacks so I can send to people who want that option.
If you have been affected by this and prefer to replace it yourself, please email me your address so I can send you one. Use the email Title "121GW Connector"
Alternatively you send your meter back to UEi at this address. I'm not sure if they will rework or replace the meter or board.
Attn: (Mr.) Heegoo Kang
Tel: 82-32-837-5777
309, A-dong, Smart Valley,
Songdomirae-ro 30, Yeonsu-gu, Incheon,
21990, Korea
UPDATE:
UEi have indicated they have fixed (or greatly improved) the resistance drift problem.
They are just working on another issue that could take another week or two before a new firmware release.
UPDATE:
UEi have indicated they have fixed (or greatly improved) the resistance drift problem.
They are just working on another issue that could take another week or two before a new firmware release.
UPDATE:
UEi have indicated they have fixed (or greatly improved) the resistance drift problem.
They are just working on another issue that could take another week or two before a new firmware release.
People have been talking about problems when long term logging to the SD-card.
Is that problem being addressed as well?
UPDATE:
UEi have indicated they have fixed (or greatly improved) the resistance drift problem.
They are just working on another issue that could take another week or two before a new firmware release.
Is this the drift I asked about during your 10ohm speed test video or is there another problem with the resistance drift?
Is the other issue they are planning to go after the one where the auto range seems to not work with a biased HV AC source?
Is this the drift I asked about during your 10ohm speed test video or is there another problem with the resistance drift?
No, it's the 1Mohm range settling thing.