Impossible Enterprises -- Octal Logic Probe V1.0 PCB

Octal Logic Probe V1.0 PCB

Especially when proto-typing with single chip computers like the PIC, SX, etc. it is often necessary to determine if multiple outputs are correct. So I created this, an octal logic probe that can be plugged directly into a proto-typing socket to view eight adjacent pins at once. Several can be used to monitor the complete chip. Don’t worry if one or two pins are analog or even tri-state, this probe wont mind and it wont affect your application either.

You get ONE (though two are shown) double sided, plated through holes, solder coated circuit board. Download and read the instructions for more details on how to construct an octal logic probe.

This is version 1 of the circuit board where a resister divider is used to set the reference voltage. It can be adapted to the LED format by extending one led lead and soldering it to the trace on the top side of the board.

Here's a ZIP file with the the schematic and board design files.

ALERT! Jameco no longer carries the MV50G [SKU 176532] Green T¾ LEDs. I'll be searching for more, but for now I only have a few sets left. I'll be contemplating making some design changes for version 2 to accommodate substitute LEDs.

From just a physical examination it looks like any 2mm x 5mm rectangular LED will fit, tightly, but fit. And perhaps a 3mm round LED for the voltage reference. You might check at Futurlec for some posibilities. I have not confirmed the voltage drop, so make sure you do.

Now for all you folk who are willing to wait for version 2.2; I need some feedback. Send me some mail telling me what you want.

2mm x 5mm rectangular LEDs — They pack well, but make the probe thicker,
3mm round LEDs — They would take up the entire top of the board leaving little or no gap between the nibbles [clumps of four bits],
A complete surface mount kit,
A fully-assembled surface mount probe, OR
Another suggestion.

And of course e-mail me if you find another source for those little green LEDs.

Sold Out

There aren't any left or at least all remaining inventory has been allocated to buyers.