Reddit:Electronics

This beast is almost impossible to carry by one person. Aside from the normal frequency counter stuff, there is a full CPU inside built on descrete ICs. Extracted boards on the last photo are arithmetic logic unit and RAM.

First project I've done on my own with no tutorial to follow. Using an L293D to drive 4 5v pumps and controlling them with 4 capacitive soil moisture probes. Working pretty good so far!

Mirrored a symbol in the schematic for better readability, got a phonecall, forgot to mirror the signals too when I continued. Did this botch so I can continue writing the firmware whilst waiting for the fixed board to arrive. So, how is your "Revision A" going?

Hey guys, trying to fix my buddy's Rock Band guitar because they go for like 500 on ebay. So there are two AAs in the battery holder, both are tested good at 1.5 volts. With the batteries installed, between the contact circled in red and both pins in the connector circled in blue, I get +1.5v. I would assume I should have +1.5v on one and -1.5v on the other. I also have 0v across the pins circled in yellow, and I would think I should have 3v. Does it sound like there's a short in the battery holder, or am I missing something here?

My bench desk

Bench

Next I want to look into making some registers, and maybe solder some cable with pins to act as a bus. Also want to buy smaller resistors, they are HUGE