Analogue vs digital power meter, different readings

And I see you are plugging it into a 4-channel Siglent. I am impressed! I am going to have to make one of those probes (not Tektronix quality of course!) because eBay at $450 USD/used is way outside my budget.

I apologize if you felt offended. I was not expecting such high level test equipment outside an Amateur Radio conversation.

$1000+ for a probe thet temperature drifts? I can build one that drifts for a lot less money. :grinning:
https://electronoobs.com/eng_circuitos_tut12_1.php
Good for you for getting those probes for a sensible price.

Not me!

Although I’ve always had a nasty test gear jones, that stuff dates back to when I was writing my Above the Ground Plane column for Circuit Cellar magazine and could turn it into a biz expense. :grin:

Still comes in handy!

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I built one of those a while back… put a better op amp in it, but if you want to measure down in the single digit mA, it’s pretty flaky… Really anything under 50mA is an issue. The more precise the ferrite loop closes around the hall sensor the better it’s performance.

Great in the amp reading area, gets much worse as you get less current and you have to bump the gain to get a scope trace without a bunch of noise…


I have bnc jacks on the cabinet and was hoping to just put one in there and leave it… Next step is the Ferris box (Faraday cage), albeit a small one to house the sensor and amplifier…

Haven’t gotten around to this yet … :thinking:


That site is kind of a problem… tried to download a couple items and it took me to a security site wanting me to install something from Firefox … :-1:

:smile_cat:

Aye!

The Tek probes slide mirror-polished split ferrite cores around the conductor, rather than clamp them together, and I live in mortal dread of scarring the surfaces by closing them on a single molecule of grit. So far, so good.

Ed, now you are dating yourself! Loved that magazine

Maybe it has something to do with your icon at the end of your messages?