ESR for Capacitor

HP 4274A.

---

• KSI@home KOI8 Net < > The impossible we do immediately. *

• Las Vegas NV, USA < > Miracles require 24-hour notice. *

The Dick Smith ESR meter designed by Bob Parker. Less than $100 US.

On Sun, 09 Jul 2006 06:39:29 GMT, "Michael A. Terrell" put finger to keyboard and composed:

Bob's meter delivers an 8us pulse at 2kHz.

The "Capacitor Wizard" uses a 100 kHz 20 mV P-P sine wave.

- Franc Zabkar

There is currently a discussion about ESR meters on sci.electronics.repair with the subject line:- MAT esr meter.

sure there is, most of it was done using 1 mhz how ever. but most of that equipment will drop to lower freqs . you need something like a capacitive bridge that has a Q option on it.

How about the old General Radio types? :))

In my experience ESR hasn't been much of a problem with non-electrolytic capacitors.

I think that Bob Parker's one is mostly useful for values > 1uF, so I would be suspicious of using it for film caps unless it is a very big film cap. It is however very good for testing electrolytics.

I don't know about the Capacitor Wizard.

Chris

On Mon, 10 Jul 2006 21:22:43 +0100, Chris Jones put finger to keyboard and composed:

I use Bob's meter and consider it an essential part of my tool kit. Nevertheless it is good to know the limitations of your test equipment. AFAICS, Bob Parker's ESR meter should read 8 ohms for a perfect 1uF cap (it actually shows much less than this). Here is my reasoning:

Here are actual measurements:

- Franc Zabkar