gathered the parts

Checked my electronic parts inventory for the dew heater controller build. I was surprised by all the parts that I already had.

From my personal supplies: a single-pole single-throw switch, 2.2 kilo-ohm resistors (4), 1N4148 signal diodes (4), diffuse red 5mm LEDs (2), male CLA plug with in-line fuse, various fuses of different ratings and speeds, and a suitable perf board. Oh, and I had small 4-40 bolts and nuts.

From the supplies provided me by my friend Dietmar Kupke I was thrilled to find: a LM556 dual timer IC, 47KΩ resistors (2), 10 nano-farad capacitors (2), and 1μF electrolytics (2). I was pleased to find a good sized black plastic project box.

I was blown away to find 2N2222 transistors (2), in the TO-18 package no less, as called for in the schematic diagram. Seen these old things but never used 'em before.

I had lots of wire: fine 22 or 24 gauge solid for signals and heavier stranded for high-amperage pathways.

Didn't know if I would need or use them but I also collected up some grommets, a fuse holder, various wire terminal blocks, and 16-pin IC socket.

From digi-key, I found: variable 1MΩ pots (2), knobs for the pots, a Schottky diode, TIP31C NPN power transistors (2) in the TO-220 package, small heat sinks for said TIPs, and RCA female connectors (4).

As expected, way less money than buying a commercial unit. In fact, 1/5th the price!

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Added to the order parts to replace missing pieces from the electronic lab. Also found battery packs for some other astro-projects...

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Next: a partial prototype.