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How about an actual schematic instead of vague blurb?
2
A cheap as chips solution:
Use an arduino to generate the pulse pattern www.arduino.cc/reference/en/libraries/pulsepattern   github.com/RobTillaart/PulsePattern

A picture is worth a thousand words.
Here's my interpretation of your description. 2149138-0

3
Repair / Fluke 1503 Insulation Tester replacement Transformer T1
« Last post by klim on Today at 12:15:01 pm »
Hi, I want to bring back by Fluke 1503 to life. The original Transformer had a shortage in winding, so i desoldered it from pcb. Now I'm looking for a replacement Transformer.
Too bad there are no technical details availible. The PCB device id is: T1. Below some pictures. I hope to get some help, many thanks in advance.

4
Updated to a perhaps the final version, where I returned to the traditional formula, which works properly only when the rundown charges are related to the "PWM charge" (56 in our case above).

The rundown range is +/- (0..27) counters diff counts (that is 56 SM clocks, also mind there is the RDN and RDNP inputs now as per the PIO source). The rundown now returns "reasonable" values, imho, which fits the both resolutions "smoothly".

For example the above runup resolution is 9800uV and the rundown resolution 175uV in 56 steps.
 
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Power/Renewable Energy/EV's / Re: Dual Complementary Rectifier PSU
« Last post by virusx2 on Today at 12:11:25 pm »
Ok, if someone could analyze this with some equations i would be glad
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Beginners / Re: Checking for noise in resistors
« Last post by strawberry on Today at 12:10:17 pm »
humidity spoils carbon resistors therefore drift
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The builder is using CA glue. What's wrong with what he chose, seems to know what he's doing. You can use SCIGrip 16 if you don't want to use that.
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Repair / Re: LED Strip lights flashing like a bad 90s rave
« Last post by RoGeorge on Today at 12:01:26 pm »
I would disconnect the LED strip and check the (group of) LEDs individually, one by one, with a DMM or with a voltage source + series resistor + 2 wires.  Could be that one of the many series LEDs is defective (interrupted) and when the voltage across it becomes too high, it short-circuit itself and lights up the rest of the strip, but at a higher voltage than it should, then the overcurrent protection turns all off, and the flicker repeats just as the defective LED would be the starter in a fluorescent tube lamp.

If not, then maybe check for dried out electrolytic capacitors in the power supply (though, they all look OK in the picture).
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Perhaps you are right.  I assumed (never a good thing, especially here) that people looking at Differential Probes have researched good practices, earthing and isolation transformers.  At any rate, that is what drove me to consider the expense.  (I grew up with non polarized plugs and isolation transformers).

But yes, since many Differential Probes were battery operated, I am interested in the impact of the use of a USB port on the scope for power.  Especailly given all the attention to the issues regarding working around USB ports.

FWIW, I did check my 120 vac with it, with no ill effects. But......
10
Test Equipment / Re: Firmware update for Gratten ADS1102CAL+ oscilloscope
« Last post by tv84 on Today at 11:56:00 am »
This is the only Atten CAL+ FW I ever saw.

Don't know what version it is.
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