Today I spent a little time working on the FOXX-3 kit. This is a really fun little kit to build. Everything is laid out well, the board is high quality and the instructions are well done.
I built the keyed and sidetone sections today. I’ve been following the test instructions which require nothing apart from the circuit, battery, earbuds, and a screwdriver. I finished the keyer and powered up the board. I pushed the switch that acts as the key expecting the relay to click over. Nothing! I tried again with the same results. Maybe the relay was really quiet. I tried again and with my ear to the relay. Still nothing!
I powered down, flipped the board and examined the soldering job I had done with a magnifier. Everything looked fine. No cold joints and no bridges. I was about to give up for the day and go onto something else when I decided to try looking again. I was beginning to fear I had fried one of the transistors somehow. I picked up the board again, and peered at the soldering. Aha! One of the transistors in the keying circuit had an unsoldered lead. The board was rotated differently when I had picked it up again. The perspective and the angle of the lighting had kept me from seeing the unsoldered lead clearly. A change of perspective definitely helps.
The lead was soldered, and the rig powered up again. I pushed the key. Nothing! Maybe I had fried one of the transistors. Touching the documented test point didn’t produce a buzz the way it had done yesterday. I suspected a short somewhere. I touched one of the diodes close to the relay. It buzzed! Keying changed the buzz. I took that to mean the relay was clicking over properly.
The sidetone section went together without issues. Powering up and testing that worked the first time.
Here are a couple of photos from today. First the recalcitent keyer. The red button is the key. Also note the connections on this rig are mounted vertically.
Keyer section complete.
The finished sidetone section. The rig has independent volume and sidetone controls.
KB3VCQ - Ham Time 