I'd like to be in for 20. Very much appreciate the efforts of those members making this possible, even if I'm in too late for this time around.
I bought 9 bags, 450pcs(50pcs in a bag). I have to open at least one bag to check when arrived today or tomorrow.
The weight of one bag is 52.5g, so 9 bags is 473g. Plus package, it may exceed the 500g limit, so I may have to ship 400pcs.
I've just search "2DW232" and "Shanghai 17th Radio Factory"(in Chinese) and got 7 entries, all the sellers are in Shanghai.
The 1st is the one I bought(having bought 5 times), The 2nd have been bought 1 time.
I've once try to put Chinese here but it won't allowed by the forum, but here I try again for Shanghai 17th Radio Factory:
??
Edit: the above two faces plus two "?" were in Chinese but showed incorrectly.
This forum does not support non-western symbols. Same with cyrillics
Hello Zlymex
Can you ship 300 pcs to EU and 150 pcs to USA? There are more people in EU who want these parts.
I've once try to put Chinese here but it won't allowed by the forum, but here I try again for Shanghai 17th Radio Factory:
??
Edit: the above two faces plus two "?" were in Chinese but showed incorrectly.
The forum software is
weird. It manages character encodings correctly up to and including previewing your own comments but then seems to completely stuff the encoding when you actually post the message.
For example, I'll type "?" here, and what's in the quote marks as, I see them, is a Greek omega. I'll hit 'preview' and, it still looks like an omega to me, now I'll hit 'post' and, based on past experience, it'll turn into "?".
Editted to add: And sure enough, that's exactly what happened. It makes the 'preview' feature half useless.
seems to be to late, but I would be interested to know if I can still join and buy 30 of it
- Norminal zero-TC current ranges from 5mA to 15mA depending on types.
These 2DW23x series(2DW232, 2DW233, 2DW234, 2DW235) has been around for many year and ....
were you able to try the diff in noise between the xx2 (5mA) vs the xx5(12.5mA)?
Every device I tested follows the inverse square root rule
Noises were all similar at given current
Zero TC current are different among xx2
Zero TC current are the same between xx2 and xx5
Package arrived today, will test tomorrow.
Can someone tell me, how all of you are gonna make use of the low noise while maintaing extremely low drift? Wouldnt it be more reasonable to just stick together a few LTZ1000 to get sqrt(n) noise reduction, while having a very low drift, backed by decades of experience?
While low noise and low drift enable many experiments, so does also low cost
I guess most are hoping this offers a combination of low cost and low noise.
Package arrived today, will test tomorrow.
I also bought 50pcs 2DW232 from the same seller,looking forward your test methods and results.
Package arrived today, will test tomorrow.
I also bought 50pcs 2DW232 from the same seller,looking forward your test methods and results.
I've just finished testing 10, powered by three lithium cells in series(12.4V noise free) and series 1k precision resistor with the test zener to get about 6.3mA test current.
The terminal marked red(may be other color) is negative, center terminal is positive, the other terminal(connected to the case) open.
Because the noise is very small, and also the TC is not tuned, the device is very sensitive to air turbulence, I covered it with a lot of tissues (wrapped around the device and legs).
The result is positive, 9 is very typical but one is a bit above average. I plotted these on the original chart with added green dots. Some dots are overlapping.
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
Hello Zlymex
Thank you for buying these parts for the Metrology community here.
I will coordinate with the other interested people to distribute the parts.
I think we should start a group buy thread and take that discussion off of this thread.
Please let me know if there is a way to compensate you for buying the parts. If you cannot receive an electronic payment, is there something you want to acquire from the USA that I can send to you via USPS/China Post that is the same value? Maybe something that is difficult for you to acquire in China but costs about the same as what you paid for these parts?
The science behind your personal metrology projects is impressive. Building your own microvolt DIY noise meter is one example. For sure, I will want some help on this thread building up a set of 4 references like the Fluke 732B .
best regards,
VintageNut
I think we should start a group buy thread and take that discussion off of this thread.
Seconded. The thanks are also seconded.
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
How is the shipping/distribution now organized?
Thank you zylmex!
hammy
zlymex,thank you!
I do a simple test for 2dw233 compare with ltflu-1.The circuit is same with the fluke5440a REF board that series two sza263(ltflu-1) then buffer output 13v.I replace ltflu-1 with 2dw233 and series 1.8k(1k should be better) foil resistor with 2dw233 to get current about 3.6mA,then test the output noise(0.1~10Hz),the ltflu-1x2 is about 1.8uV(vpp),the 2dw233x2 is about 1uV(vpp). :-+The problem is the 2dw233x2 output voltage is not stable, The matter needs to bo resolved.
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
How is the shipping/distribution now organized?
Thank you zylmex!
hammy
I've just sent a PM to VintageNut, the shipping company(EMS) requires the telephone number of the receiver.
zlymex,thank you!
I do a simple test for 2dw233 compare with ltflu-1.The circuit is same with the fluke5440a REF board that series two sza263(ltflu-1) then buffer output 13v.I replace ltflu-1 with 2dw233 and series 1.8k(1k should be better) foil resistor with 2dw233 to get current about 3.6mA,then test the output noise(0.1~10Hz),the ltflu-1x2 is about 1.8uV(vpp),the 2dw233x2 is about 1uV(vpp). :-+The problem is the 2dw233x2 output voltage is not stable, The matter needs to bo resolved.
Nice work.
It seems to be some 50Hz noise on the photo of the oscilloscope.
The instability of 2DW233 may result from the air flow around the TO-39 case which can be minimized by fillers of soft and insulated material around 2DW233 and the pins on both side of the PCB. Try tissue first.
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
How is the shipping/distribution now organized?
Thank you zylmex!
hammy
I've just sent a PM to VintageNut, the shipping company(EMS) requires the telephone number of the receiver.
I sent a PM with my phone number. Thank you very much for doing this very kind thing!
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
How is the shipping/distribution now organized?
Thank you zylmex!
hammy
We will start a new thread for the group buy if the 2DX233 parts that Zlymex has kindly purchased for the group here on this thread.
I've packed 430pcs up and ready to ship to VintageNut/USA tomorrow.
How is the shipping/distribution now organized?
Thank you zylmex!
hammy
I've just sent a PM to VintageNut, the shipping company(EMS) requires the telephone number of the receiver.
I sent a PM with my phone number. Thank you very much for doing this very kind thing!
Received and the package is shipped.
Zlymex, pls read your PM, regarding zones, I'm alone in my region.
Zlymex, pls read your PM, regarding zones, I'm alone in my region.
I read your PM but I'm not sure what you need apart from request 20 samples of 2DW232 for which you can contact VintageNut. I'm here only responsible for shipping to one oversea location(USA).
Look what a member of my local Makerspace has drawn for me, will be printed next week and hopefully fits 2DW23X and also TO-99 (LTZ1000). At the club we print with PLA which is not suitable for high temperature, ABS can be printed but it seems to need tighter parameter control or something, so no one there likes to print it. Mounting holes are M2. Will publish STL file. The thick wall will be flled with a air chamber structure by the slicing software, giving better isolation than solid material.
Best regards
Hendrik.
I have access to a DLP printer (layer thickness 25µm - 150µm, window size 70 x 40mm² with 1920x1080px, maximum part size 400 x 330 x 200mm³).
I printed a LTZ1000 spacer some months ago using a material called PLASTCure Rigid 10500, but a material called PLASTCure Clear 100 (transparen) is available too.
If there is a bigger interest I could offer such caps for small budget by printing a complete batch of such caps.