Hi The “thermoelectrc chamber” in that paper *is* the gizmo. There is / was a better paper diving into the unit in a bit more detail. Even that did not get down to issues like the controller, the driver, or the power consumption. Indeed one wonders if there is a giant heatsink and fan on the bottom of the unit ….. again, no real information.
Bob > On Jul 12, 2019, at 7:11 PM, Bruce Griffiths <[email protected]> > wrote: > > Figure 5 in http://www.wenzel.com/wp-content/uploads/Sub-pico-Multiplier.pdf > ?? > Bruce >> On 13 July 2019 at 05:23 Bob kb8tq <[email protected]> wrote: >> >> >> Hi >> >> If you do go the TEC route, plan on a fairly big power source :). There is a >> Wenzel doc on doing a TEC based enclosure using a couple of die cast >> boxes. The pictures don’t show what they used to drive the beast so part of >> it would still be up to you. My search skills and their web site are not >> quite >> compatible so no link …. sorry !!! >> >> Bob >> >>> On Jul 12, 2019, at 12:12 PM, Javier Herrero <[email protected]> wrote: >>> >>> Hello, >>> >>> A TEC is good if you want to maintain the resistors at 25ºC, that seems the >>> zero TC point for some precision low TCR resistors (for example, the Vishay >>> VFCP or VSMP series) >>> >>> Regards, >>> >>> Javier >>> >>> On 12/7/19 10:06, Dr. David Kirkby wrote: >>>> On Fri, 12 Jul 2019 at 08:07, Bernd Neubig <[email protected]> wrote: >>>> >>>>> AXTAL has a miniature oven for heating precision resistors or other >>>>> components to a constant temperature. It is housed in a small DIP8 >>>>> package. >>>>> See attached AXR135 data sheet. >>>>> Optionally this device can be offered unsealed, ready for inserting the >>>>> component by yourself >>>>> >>>>> Regards >>>>> Bernd >>>> >>>> The resistors I am using are made by Caddock, are 1 M ohm & 10 M ohm, 0.01% >>>> tolerance and 5 ppm / deg C. They are much too large to fit in a DIP8 >>>> package. A quick check with a ruler indicates that the 10 M ohm is 38 x 12 >>>> mm and the 1 M ohm is 19 x 10 mm. >>>> >>>> A quick photograph shows this half finished project. Unfortunately, even >>>> before I have finished it, I am wishing I had done a better job. However, >>>> my original reason for doing this was to check the stability of a data >>>> acquisition unit before sending it to Keysight. I think this will be good >>>> enough for that, but I could certainly have done a job with some thought. >>>> >>>> The thermocouple is just meant to be a temperature sensor that dissipates >>>> no power. A thermistor or RTD buried in the polystyrene would have just got >>>> hot. The resistors should not get hot, as the power dissipated will be >>>> under 1 uW. >>>> >>>> I also intend putting in a 100 M ohm resistor, but the specification of >>>> that is much poorer (5%, 100 ppm/ deg C. ) >>>> >>>> I partially read the paper mentioned. I note that the authors used a thermo >>>> electric cooler (TEC) as they wanted get low temperatures. I assume that >>>> for crystals or resistors dissipating little heat, a TEC would be >>>> unnecessary, and just a resistor acting as a heater would be fine. But will >>>> read some of the references. Obviously for controlling a crystal >>>> oscillator, or my resistor, stability is most important, whereas for the >>>> authors of the paper, stability was not their major concern. >>>> >>>>> -- >>>> Dr. David Kirkby, >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>> >>> -- >>> --------------------------------------------------------------------------------- >>> Javier Herrero >>> Chief Technology Officer EMAIL: >>> [email protected] >>> HV Sistemas S.L. PHONE: +34 949 >>> 336 806 >>> Teide 4, Núcleo 1 Of. 0.1 FAX: +34 949 >>> 336 792 >>> 28703 San Sebastián de los Reyes - Madrid - Spain WEB: >>> http://www.hvsistemas.com >>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
