Keithley DMM6500 IR decoding possible?

[JimKnopf]

I was inspired by @Martin72 feature request in the Siglent SDS2000X HD thread https://www.eevblog.com/forum/testgear/siglent-sds2000x-hd-missing-features-and-bugs/msg4518173/#msg4518173 where he whishes an IR decoder from Siglent for testing IR Remotes on Oscilloscope using a so called Silver-Bullet Oscilloscope Infrared-Receiver (found it here https://www.analysir.com/blog/product/silver-bullet-oscilloscope-infrared-receiver/).

I've build my own one soldering an 8,2k Ohm 0805 resistor on a IR LED. Works nice on Oscilloscope with the downside of a missing decoder.

The DMM6500 has a Digitizer mode to measure Voltage and can measure 1 Mega-Samples per second. Not as much as the SDS2000X HD but maybe sufficient to capture IR signals. The result looks not too bad.

Does anyone ever made a script for decoding IR signals for the DMM6500 or can guide me to write a script?

[Swake]

Thanks for the tip of using that IR receiver diode.

[Kleinstein]

The DMM may have too much input impedance to use the detector with 8 K. It may still work with a smaller resistor (e.g. 470 ohm) and sufficient intesity.

[egonotto]

Hello,

why do you need a series resistor for the IR LED? The IR LED works as a sensor and converts IR light into voltage.

Best regards
egonotto

[voltsandjolts]

Parallel resistor is current to voltage converter.

[JimKnopf]

I did some tests, i startet without a resistor. But the signal shape doesn't look that great. 8.2k was the best signal shape to me.

[JimKnopf]

Another batch of screenshots.

[JimKnopf]

The 8.2k resistor was the winner. I tested with a resistor decade using values i had in my shelf.
Second image are 3 different types of IR LED without a resistor.