I just received and built the N0XAS Pico Keyer (now the Pico Keyer Plus). It costs only $18 (plus shipping), and is a very cool kit and a useful addition to one’s shack.
As shown in the photo at right, the PicoKeyer measures only 2-in. x 1-1/8-in. On the board, are only 12 components: one resistor, one IC, three capacitors, one switch, two miniature phone jacks, two transistors, a small speaker, and a battery. It took me less than a half hour to solder all the components to the board, and it worked perfectly when I inserted the battery into the battery holder.
The key component is the eight-pin PIC processor. It’s the processor that gives this keyer its flexibility, and it has a raft of very cool features. Some of the ones I like a lot are:
- Four message memories. You can program up to four messages into the PicoKeyer. To play them back, you have to hold down the switch until the processor cycles around to the message you want. In normal operation, this is not a big deal, but you won’t be using this feature in contests.
- MCW mode. This is a feature that I haven’t seen on any other keyer. In this mode, the keying output is closed when sending. This lets you use this output to key your VHF/UHF rig, while feeding the audio into the mike input. You will probably still need a pot to adjust the output level, but that’s not a big problem. This is the next thing that I’m going to try to do with this kit.
- Analog speed control. You can add an external pot to set the speeed. This is a nice feature as doing it via the command mode could take several seconds to do, and that’s really too much time while you’re in a QSO.
- Battery or external power. You can power the keyer with either an internal battery (the CR2032 show in the photo) or external power supply. To use an external supply, you have to add a capacitor and voltage regulator (not included).
As you can see in the photo, I mounted the PicoKeyer in an Altoids tin. This is the first time I’ve used an Altoids tin for an enclosure, and they really are handy little enclosures.
The PicoKeyer is so small, that there’s room for some other stuff, too. For example, when I use it in MCW mode, I will have to add a small pot. Another possibility is to add a small audio amp to boost the audio output.