Over the years, I would once in a while supply homebuilders with "Plug and Play" Digital readout kits.

I stopped doing this because:

1) When I sold the XS3 product line to Graves, I sold them all the rights and technology. These designs are no longer my property.

2) Because of ROHS regulations and the naturally fast pace of the electronics industry most of the parts for the XS3 original circuit are no longer made. The original LCD design that appeared early on these pages was already based on a surplus meter from the type of places that sell them, and they are of course long obsolete.

3: There were abuses by commercial entities who were attempting to build a for-sale product. They failed, but the intent was there.

4: And finally, the crowning event, which must be seen to be believed.

A few years ago I sold someone a kit. Recently, I got a complaint about the display jittering.

The following pictures are the "defective" device I was sent. MINERAL ACID SOLDERING PASTE WAS USED, and the meter was CARVED UP to fit a case.

Look at this.

The deliquescence from the flux had wicked into the meter's gain trimpot.

Look, this is not rocket science. It's just a half bridge voltage divider and a good 2V meter, with the best pot you can buy and critically regulated DC supply.

Here is the generic circuit principle. If you can read a simple schematic and can be trusted wth a soldering iron, go for it:

When I have to warranty things like those pictures, I think you will agree that Mother Theresa would lose patience.


I will not reply to requests for Digital Readout kits, plans, etc. I have been out of that business for years, and as you can imagine from the above pictures, I do not miss it one damned bit.

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