After reviewing my Rock-Mite build compared to other peoples builds on the Internet, I noticed that I hadn’t grounded my crystal cases, so I took the thing apart again to do this. I used some segments from a paper clip to do this.
I finally got around to the smoke test with a 9V battery… and got some smoke 🙁 I unplugged straight away and checked everything. The smoke seemed to come from the back of a resistor, there was no short so I’m not sure if it was just some left over flux burning off. I tried a second bench test, and this time everything seemed okay, so I moved on to the MyDEL MP-6A I’ve bought to power the thing. Again, everything seemed fine. I tested gain and the switch on the front… and thats where things started going wrong, the Morse code for “S” beeped through my earphones, and then got quicker and quicker until it was almost a single tone, and then eventually got a small bit of smoke from Q6 (the 2N2222A). I had no antenna plugged in at this point, so the thing must have been transmitting, maybe due to a short.
Now when I plug in, I get all sorts of weird and wonderful things happening. I will plug it in, and it will produce a small amount of static through the earphones. Then eventually it will produce a …– then a single lower . tone, then …– again then it does the same thing and slows down, then it gets fast and faster until its justs a series of beeps. If I re-plug it back in straight away, or within a few minutes, I just get one series of … then it speeds up to become a continuous stream of …………….. .
I’ve emailed Dave at Small Wonder Labs and he’s started to help me work out what the problem is, but I’ve found my multimeter isn’t working so I’ve ordered a new one so I can start testing for the problem, or problems…