Soldering 101
From Fixme.ch
Intro to through-hole soldering
We will solder a blinking, customizable name tag. We will also discuss and explain the design and the theory of operation.
Circuit
- A discrete astable BJT multivibrator feeding into a johnson decade counter, which drives the LEDs directly.
- The counter can serve up to 10 segments.
- The LED matrix can partitioned partitioned arbitrarily column-wise: multiple columns can be grouped onto a single counter output.
- each counter output has one series current limiting resistor
- last (unused) counter output feeds back to reset
- multivibrator speed can be adjusted with a pot
- on/off switch?
Components
- LED, $0.04650 @ 1000: http://search.digikey.com/us/en/products/WP710A10SRD%2FD/754-1593-ND/2769819
- CD74HC4017 decade counter, $0.4776 @ 50: http://search.digikey.com/us/en/products/CD74HC4017E/296-25989-5-ND/480317
- CR2032 holder, $0.4968 @ 100: http://search.digikey.com/us/en/products/3003/3003K-ND/227448
- PCB 5cm x 10cm, $1.498 @ 50: http://www.seeedstudio.com/depot/fusion-pcb-service-p-835.html
