Date: Thu, 28 Jun 2001 22:27:03 -0400

Author: John Cockman

Subject: Re: [Fwd: Re: Large Digital Multimeter]


I bought two cheap ToolKit multimeters, and removed the LCD panel from one.
Because of the electronics backing the panel, it was impossible just to
"chop" through the back. We then wired the signal from the second meter to
the disembodied LCD display. It works great for overhead projection, with
beautiful contrast, but it was no easy solder job. All I have left to do is
put it all in a box...

Appalachian State University

----- Original Message -----
From: Machele Bailey
To: Tap-L Tap-L
Sent: Thursday, June 28, 2001 9:30 AM
Subject: [Fwd: Re: Large Digital Multimeter]

> About a week ago, I asked Mike about making a large digit multimeter for
> lecture demos. Here's one thought he had....
> -------- Original Message --------
> Subject: Re: Large Digital Multimeter
> Date: Wed, 27 Jun 2001 22:25:46 +0100
> From: Mike Harrison
> Reply-To:
> Organization: White Wing Logic
> To: Machele Bailey
> References: <>
> <>
> I just had another thought on this - if you have an overhead projector
> available, it would probably not be that hard to convert a cheap LCD
> DMM display for 'transparent' mode - like those old OHP computer
> displays. If you're lucky you may even find a model built in such a
> way that you could just chop a hole in the back to let the light in.
> You'd need to remove the rear reflector from the LCD, and the rear
> polariser will probably come off with it, so you'd have to add a new
> rear polariser. This might make a very cheap and effective solution if
> you can find a unit that is amenable - DMMs usually use low LCD
> multiplex rates, which means that contrast should be good enough to do
> this.