I mentioned on the LTZ1000 thread that I was interested to see what Awesome14's D-105 could do so I was buying one. It came yesterday. In the interest of more light and less heat, here is what I've found so far. The results are not metrology lab measurements -- they are a guide only, but I've provided enough info to make the results useful. One note -- I have thought for a while that my HP 3458A is reading 10VDC about 6ppm high, although it is in spec....
Calibratory D-105 10V standard evaluation, started on 2-7-15
Instruments used in evaluation:
— HP 3458A, calibration checked on 7 Aug. 2014, by Keysight in Loveleand — no adjustments made, found to be completely in spec; this is the standard model — 8ppm ref board. Used to monitor 10V standard outputs. 3458A powered on for last 6 days; internal temp 36.5 °C. ACAL 1 (DC) run at 4:30PM. NPLC=60, NDIG=8
— HP 3456A, cal’d against HP 3458A. Used for monitoring ambient temps with Pt100 RTD.
— Heath 2718 Linear Triple Bench Supply — each 20V supply powering one standard..
— Geller SVR (not the temp comp unit), purchased in 2007, used for approximately 12 hours total since then up to this time. On for the last 8 hours (included in total of 12), since 8AM with 15VDC power. Geller’s 2007 certificate says 10.000 00V, Tolerance 5ppm/°C, 15ppm/1k hrs. Cal’d at 23°C ambient.
D-105 unboxed in lab at 4PM. Connected to bench supply at 14.5VDC, initial ambient temp at case 23.0 °C. Ambient measured immediately adjacent to and in between the two standards, all sitting on top of an HP 8904A that was powered off — makes a handy stand with some thermal mass.. D-105 output started a few hundred microvolts below 10V, quickly rose to 10.000 05VDC. Calibratory’s certificate says 10.000 0014V, cal’d at 20°C ambient.
Both the Geller SVR and the D-105 outputs are connected with 24ga. solid copper insulated wires (old-school telephone extension wire) to gold flashed dual banana plugs to ease connections to the 3458A. The wires are soldered to the Geller SVR and clamped in the gold-flashed bindind posts of the D-105.
Elapsed time Ambient Geller SVR D-105
for D-105 °C
0.6 hr 23.5 10.000 060 10.000 058
3.4 hr 22.9 10.000 071 10.000 068
5.3 hr 23.6 10.000 060 10.000 066
6.4 hr 23.8 10.000 053 10.000 068
Overnight break in measurements with lab cool-down to thermostat set 66°F, reheat in AM to 71°F; standards left powered on.
20.1 hr 22.4 10.000 092 10.000 078
22.5 hr 22.5 10.000 088 10.000 078
Moved to warmer location on top of HP 3456A, standards and RTD grouped as before.
22.8 hr 28.9 10.000 017 10.000 047
23 hr 29.3 10.000 002 10.000 042
24 hr 29.5 9.999 997 10.000 043
Standards powered down. Will begin from room ambient start in 18 hours or so.
At this point, a simple "box" of drift v. temp shows that average drift for the D-105 is approximately 0.5ppm/°C; the Geller SVR average drift is approximately 1.4ppm/°C (pretty good).
I think that about covers it, unless I neglected something? Can anyone think of additional features and characteristics this device should have?
...what the SVR-T and D-105 are supposed to be.... *NOT* something that you would use to maintain a stable volt in your laboratory long-term.
@richiem:
That's a bit unfair to the Geller design, because you are not using the temperature compensated SVR-T, so you are comparing apples to oranges. I suspect the Geller SVR-T would be almost a straight line with temperature, as that is what he obtained for each unit in his micro-chamber after adding the thermistor and "tuned" resistor. Note that the TC of resistors [and therefore monolithic voltage reference outputs] does not change with time unless they are severely abused [like super high temperature exposure, etc.]. So, once a TC is obtained and set, there is no reason to do it again, any only the voltage offset will need trimming from time to time, and this is mainly due to resistor absolute value drift.
Can you borrow an SVR-T from someone and run the test again of the D-105 vs. SVR-T?
The price of the D-105 is US $97.95 today....
My guess is that the sales went to zero after Awesome14 raised the price, so he put it back. This is good to know-- it seems the "threshold of pain" for the "Arduino crowd" appears to be about US$100 for this kind of device.
Either I had some browser cashing issues or the price goes up and down. US $157.95 for the 2ppm version now?
He also lists a 6ppm version for $59.95
@Awesome14:
Just curious, how much did Fox Valley charge you for the calibration for the 732A?
QuoteBefore I post any thing on line I do a quick check, "would I say that to my boss or a friend?"
I strongly support peer review and positive criticism, but it should always be done in a objective way preferably supported by analysis or prior art.
It should never be an attack on the person, his believes or his culture.
I feel the same way, but here it's a different story. It's plain and simple: scam.
No problem if a guy is using a sloppy breadboard reference in his own lab and believes in magic and unrealistic specs. But selling a black box with false claims (2ppm and esoteric bullshit description) for a horrendous price is scam. And I have no mercy for that, especially on ebay where you need to trust the seller when buying stuff. it's like selling 32GB USB sticks that only have 1GB chips inside. Plain and simple scam
I don't see any heatpipes in the teardown
Maybe he thinks all the plated holes in the perf board are heat pipes. After-all, they're metallic and kind of pipe shaped
If you look at the pictures....and try to decipher Awesome14's comment....this is what I believe he is saying....
He has glued a piece of copper foil, between a diode, and the ref IC case....he is calling that a "heatpipe". Ok it's not. I think he is saying that he is cooking that poor little diode, and expecting that a thin piece of copper foil is somehow transferring enough thermal energy from the poor little diode (which is his "heater") to "stabilize" the REF IC. The efficiency of heat transfer across that piece of foil is nil. Also the diode is right next to a shit bottom of the barrel trimmer....which hasn't even had the wiper screw glued in place. So in essence he is creating more of a problem than solving one. The majority of heat (which is hardly any) is not traveling across the copper foil to the REF innards....it's just traveling, via convection, into the case of the trimmer.
Ok fine...even then I doubt this has any significant impact on anything in this circuit. If his theory is to heat the case of the REF then why not just take some nichrome wire...zig zag it across the top of the REF IC case....bond it thermally and run some current through it? That would be far more efficient than his method....and still that isn't the proper way to ovenize this package.
This all could be avoided...by simply designing a proper PCB....with a thermal layer...bonded to a TO (can) REF IC, in the dead bug config....bond the case of the TO package to the thermal layer with some thermal "grease"....and then bond a proper controlled heater to the thermal layer....just like everyone else does....
Instead he claims this is somehow innovative, and we are all too stupid too see it....I am sorry but I am all for helping people, but not when they act like some elitist and call everyone here inferior....ESPECIALLY when they have ZERO basis in their claims...NO data to prove anything and start talking about being handed circuit designs from God himself....throw in vampires, angles, and whatever other bullshit is flying out of this guys mouth, and I just don't feel like being nice anymore....
I said back on page one, that the REF102C is in fact an excellent monolithic ref IC.....I have worked with them many times, and if you hand select (bin) the IC, you can easily get better than 2ppm per year stability....out of the plastic package. No big deal there.
What I am amazed at is that DESPITE the poor layout and construction of Awesome14's "reference" the Ti REF102C is getting anywhere near 2ppm stability (+/- so 4ppm really) for even a day or two....I still see zero data showing anything about stability over 30, 90, 180, 256,etc etc etc days....
If anything I say this whole scenario just shows how good the REF102C can be....even when someone who has no idea what they are doing slaps one together with perfboard....shit components and construction techniques....
Again I have used the REF102C in a proper ovenized enclosure design...with proper supporting components, and it's a nice little IC, for a reasonable cost.....easy to implement etc etc etc....and IF you hand select the IC you CAN get better than 1.5ppm stability over a year or more....fine, no big deal...that is not innovative, astounding or anything other than "decent".....
The claims of "heatpipes" and "revolutionary design"....and then insulting us all on the basis that since we don't agree, we are somehow mentally inferior and closed minded...is simply going past the point where I feel like lending any advice or being a nice guy....
So again the only conclusion here, is that DESPITE Awesome14's total ignorance and terrible mental disabilities, the REF102C is a half way decent REF IC....I am mainly still here reading and commenting, because I find this entire thread utterly hilarious, on the basis of the divine claims, breaking the laws of physics claims, assassination conspiracy etc etc etc....it's pure comedy at this point....nothing anyone says here is actually going to help Awesome14, he is far beyond that....
To top it off Awesome14 is SELLING these on eBAY....with bogus descriptions....no pictures of internals....and for a price that doesn't justify anything he has done. Anyone here or there could easily order the same IC from Mouser or Digikey or wherever, for not much money...slap it on a perfboard...with half way decent components....throw it in a hammond enclosure and probably have BETTER results, for under $50.
So basically this is an eBAY scam, and constitutes fraud....and that is simply shameful....there is nothing innovative or "magical" about the "product"....it's built on nothing more than an application schematic handed down from Burr-Brown to Ti and then from Ti to Awesome14....and he didn't even implement it properly....why would anyone want to help this guy? He is scum...
And if you take a good look in this thread, you will see the firsts attacks come from awesome14.
I agree, in the start, it was looking good, with good points on how to do, and how to evaluate this kind of circuits. But when the people from this forum started to try to get real tests, then the maker came and start to try make everyone to think the same way he does.
Using non-scientific things to explain the circuit, blah blah...
Then, after he show some attacks to whom disagree from him, the things come more comedy... From some pages there is nothing but funny posts, from one side or another.
No big deal. There is somethings that we don't really say to someone, but if he is concerned about this, stop to say something to us (like all that crap about how he get the circuit from heavens, or something about vampires, about the cardiologist who know so much of electronics, about death attempts, how all this are connected to some voltage reference circuit?)
More than a scam, it is a troll.
I would be fun to have a community effort to design an easy DiY EEVblog voltage standard.....NOW that sounds like fun, because we could all measure our "identical" standards against eachother....and log the results....which would actually be a HUGELY useful set of data to take academic indicators from.....imagine a loose comparison of a few dozen identical standards, against all the varying conditions each individual "lab" has.....that sounds like a nice statistical effort and might actually lead to some discovery, for those that don't have any experience in this field and want to learn....and even those who think they know alrady
I have research data to prove my claims.
QuoteBefore I post any thing on line I do a quick check, "would I say that to my boss or a friend?"
I strongly support peer review and positive criticism, but it should always be done in a objective way preferably supported by analysis or prior art.
It should never be an attack on the person, his believes or his culture.
I feel the same way, but here it's a different story. It's plain and simple: scam.
No problem if a guy is using a sloppy breadboard reference in his own lab and believes in magic and unrealistic specs. But selling a black box with false claims (2ppm and esoteric bullshit description) for a horrendous price is scam. And I have no mercy for that, especially on ebay where you need to trust the seller when buying stuff. it's like selling 32GB USB sticks that only have 1GB chips inside. Plain and simple scam
My device promises certain performance criteria. It lives up to it's claims. If I can demonstrate financial losses due to your reckless and untruthful comments, be prepared to pay those damages. It is no scam! Until you can prove that any claim I make is false, it would be best not to dig the hole any deeper. I have research data to prove my claims. You have nothing to disprove them. Let's just stick to professional opinions and leave the rest at the door.
I don't see any heatpipes in the teardown
Maybe he thinks all the plated holes in the perf board are heat pipes. After-all, they're metallic and kind of pipe shaped
If you look at the pictures....and try to decipher Awesome14's comment....this is what I believe he is saying....
He has glued a piece of copper foil, between a diode, and the ref IC case....he is calling that a "heatpipe". Ok it's not. I think he is saying that he is cooking that poor little diode, and expecting that a thin piece of copper foil is somehow transferring enough thermal energy from the poor little diode (which is his "heater") to "stabilize" the REF IC. The efficiency of heat transfer across that piece of foil is nil. Also the diode is right next to a shit bottom of the barrel trimmer....which hasn't even had the wiper screw glued in place. So in essence he is creating more of a problem than solving one. The majority of heat (which is hardly any) is not traveling across the copper foil to the REF innards....it's just traveling, via convection, into the case of the trimmer.
Ok fine...even then I doubt this has any significant impact on anything in this circuit. If his theory is to heat the case of the REF then why not just take some nichrome wire...zig zag it across the top of the REF IC case....bond it thermally and run some current through it? That would be far more efficient than his method....and still that isn't the proper way to ovenize this package.
This all could be avoided...by simply designing a proper PCB....with a thermal layer...bonded to a TO (can) REF IC, in the dead bug config....bond the case of the TO package to the thermal layer with some thermal "grease"....and then bond a proper controlled heater to the thermal layer....just like everyone else does....
Instead he claims this is somehow innovative, and we are all too stupid too see it....I am sorry but I am all for helping people, but not when they act like some elitist and call everyone here inferior....ESPECIALLY when they have ZERO basis in their claims...NO data to prove anything and start talking about being handed circuit designs from God himself....throw in vampires, angles, and whatever other bullshit is flying out of this guys mouth, and I just don't feel like being nice anymore....
I said back on page one, that the REF102C is in fact an excellent monolithic ref IC.....I have worked with them many times, and if you hand select (bin) the IC, you can easily get better than 2ppm per year stability....out of the plastic package. No big deal there.
What I am amazed at is that DESPITE the poor layout and construction of Awesome14's "reference" the Ti REF102C is getting anywhere near 2ppm stability (+/- so 4ppm really) for even a day or two....I still see zero data showing anything about stability over 30, 90, 180, 256,etc etc etc days....
If anything I say this whole scenario just shows how good the REF102C can be....even when someone who has no idea what they are doing slaps one together with perfboard....shit components and construction techniques....
Again I have used the REF102C in a proper ovenized enclosure design...with proper supporting components, and it's a nice little IC, for a reasonable cost.....easy to implement etc etc etc....and IF you hand select the IC you CAN get better than 1.5ppm stability over a year or more....fine, no big deal...that is not innovative, astounding or anything other than "decent".....
The claims of "heatpipes" and "revolutionary design"....and then insulting us all on the basis that since we don't agree, we are somehow mentally inferior and closed minded...is simply going past the point where I feel like lending any advice or being a nice guy....
So again the only conclusion here, is that DESPITE Awesome14's total ignorance and terrible mental disabilities, the REF102C is a half way decent REF IC....I am mainly still here reading and commenting, because I find this entire thread utterly hilarious, on the basis of the divine claims, breaking the laws of physics claims, assassination conspiracy etc etc etc....it's pure comedy at this point....nothing anyone says here is actually going to help Awesome14, he is far beyond that....
To top it off Awesome14 is SELLING these on eBAY....with bogus descriptions....no pictures of internals....and for a price that doesn't justify anything he has done. Anyone here or there could easily order the same IC from Mouser or Digikey or wherever, for not much money...slap it on a perfboard...with half way decent components....throw it in a hammond enclosure and probably have BETTER results, for under $50.
So basically this is an eBAY scam, and constitutes fraud....and that is simply shameful....there is nothing innovative or "magical" about the "product"....it's built on nothing more than an application schematic handed down from Burr-Brown to Ti and then from Ti to Awesome14....and he didn't even implement it properly....why would anyone want to help this guy? He is scum...
I am not required to show internals on eBay. Nothing in my listing constitutes fraud. People have commented in this thread that the device is "dead on" according to their meters. I'm not at all ashamed of a +-2ppm standard that works. It even holds its calibration when shipped powered down. Many people have evaluated this product, and not one has found my claims to be incorrect. I feel sorry for you. You have no ground to stand on, so you resort to unfounded personal attacks. I doesn't bother me what you think of me. But please don't level unfounded criticisms against my invention. Thank you for your kind consideration in this matter.
And if you take a good look in this thread, you will see the firsts attacks come from awesome14.
I agree, in the start, it was looking good, with good points on how to do, and how to evaluate this kind of circuits. But when the people from this forum started to try to get real tests, then the maker came and start to try make everyone to think the same way he does.
Using non-scientific things to explain the circuit, blah blah...
Then, after he show some attacks to whom disagree from him, the things come more comedy... From some pages there is nothing but funny posts, from one side or another.
No big deal. There is somethings that we don't really say to someone, but if he is concerned about this, stop to say something to us (like all that crap about how he get the circuit from heavens, or something about vampires, about the cardiologist who know so much of electronics, about death attempts, how all this are connected to some voltage reference circuit?)
More than a scam, it is a troll.
Show me one place where I did anything but tell the truth. I didn't attack anyone.

My device promises certain performance criteria. It lives up to it's claims. If I can demonstrate financial losses due to your reckless and untruthful comments, be prepared to pay those damages. It is no scam! Until you can prove that any claim I make is false, it would be best not to dig the hole any deeper. I have research data to prove my claims. You have nothing to disprove them. Let's just stick to professional opinions and leave the rest at the door.