Post Created date
High voltage, low current reference.
gchapman, I didn't know 3 terminal regulators were available to this high a voltage. I will order a couple and tinker with them. It is probably a better solution than the descrete...
Tuesday, 19 November 2013 - 11:54
High voltage, low current reference.
Jim, Thanks, A.
Monday, 18 November 2013 - 21:07
High voltage, low current reference.
Jim, The source is high side with load connected to ground. The 350VDC is not a problem. I have a stable supply for this. What I am looking for is something similar to the...
Monday, 18 November 2013 - 18:15
DAC range limited?
Freaks, I am sorry it has taken so long to respond. I was not aware of the residual voltage at the bottom end of the D/A's range. Guess I should read a little more. With the O/P...
Sunday, 17 November 2013 - 13:52
Colpitts and temperature change.
Who-me, I had thought of this but there can be an issue if the ball becomes stuck. The viscometer is connected to another processor that handles measurement and fluid control. I...
Wednesday, 28 August 2013 - 13:07
Colpitts and temperature change.
ront1234, Thank you. I understand why the testing of long term accuracy would be important but I think I have managed to design a little bit of flexibility into the program to...
Wednesday, 28 August 2013 - 01:46
Colpitts and temperature change.
Chuck, I was able to scrounge up the silver micas form my retired parts bin but alas they were way to small for the design. I decided to remove the SMD type caps and replace them...
Tuesday, 27 August 2013 - 19:41
Colpitts and temperature change.
Who-me, You are correct sir! The current standard uses two detectors, approximately 3" apart. They are several advantages to this but in our application a few disadvantages. In...
Sunday, 25 August 2013 - 14:34
Colpitts and temperature change.
Chuck, The conductivity of the ink is tightly controlled in manufacturing so we can count on this as being a constant. Final calibration will have ink in place and should zero out...
Saturday, 24 August 2013 - 18:40
Colpitts and temperature change.
jayjay, At this point I suspect the caps. One way or the other, I should know by Tuesday. David, The viscosity of the fluid in the system needs to be fairly stabile. ( I know that...
Saturday, 24 August 2013 - 15:28
Colpitts and temperature change.
ront1234, The gain for the oscillator is set to approx. 10. This produces a clean square wave. At all temps the rise and fall time of the wave is consistent and stabile. With the...
Saturday, 24 August 2013 - 14:14
Colpitts and temperature change.
David, The trick is to measure the time it takes for the ball move between two fixed points through the ink. Precision to 1/100s is required for my particular application. I know...
Friday, 23 August 2013 - 22:03