Author Topic: Tekway DST1102B Vertical amp drift  (Read 8887 times)

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Offline dimlow

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Re: Tekway DST1102B Vertical amp drift
« Reply #25 on: April 02, 2011, 11:48:32 pm »
This interested me so i made a little animated gif of the warm up on the rigol. Each frame of this anim was taken at 1 minute intervals. the first few frames i had made the mistake of not measuring channel 2. It took about 16 minutes for the scope to fully settle down.

EDIT: More detail, first i let the scope warm up for about 2 hours, I then self calibrated the scope and set up my channels to 20mV/Div and 200ns/Div. Switched the scope off for 5 hours. Then the test was made by saving a bitmap every minute until the scope settled to 0 offset. Ambient Temp was 20 Deg C

« Last Edit: April 02, 2011, 11:59:44 pm by dimlow »
 

Offline rf-loop

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Re: Tekway DST1102B Vertical amp drift
« Reply #26 on: April 03, 2011, 01:34:50 pm »
Scopes are individuals.

Alll these 6 randomly selected units have been power off enough to stabilize to room temp as it is... around 22 now. All these started exactly same time. (time on window is related to time when I save it to USB) with same settings as can see in pics. In this test all inputs are open.

Scopes are on the same table. Scopes are NOT selfcalibrated before tests. (yes they are selfcalibrated but this time only randomly warmed and random temp.. selfcal have only do for "check".

Also I think this random sample is not so that that there are most good and most bad  units... I think there can find more bad and more good if can select from big lot of scopes.

Captured time is only ~11min but most of drift happend in this time and it also give enough information what is going on.
Do not look zero line. (look only amount of drift)

All these 6 units are newest HW and  serial numbers are near each others.

(do not worry, same is with Agilent and Tektronix also, but not just this amount what is in most bad unit....maybe quality variations are not so big... and of course then with all others and finally also of course in these cheap oscilloscopes.)

If people have good luck.... this is lottery:



« Last Edit: April 03, 2011, 02:06:17 pm by rf-loop »
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Offline saturation

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Re: Tekway DST1102B Vertical amp drift
« Reply #27 on: April 03, 2011, 01:43:36 pm »
Thanks for actually making photos and animations of this.  Its a reason to warm up any device before using it for precision work  and that modern instruments still require it.
Best Wishes,

 Saturation
 


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