PA1JIM » BC547 http://www.pa1jim.nl eNotes & net.presence of Jim Fri, 06 Jan 2012 09:30:02 +0000 en hourly 1 http://wordpress.org/?v=3.3.1 Voice Keyer part 3 http://www.pa1jim.nl/2009/06/voice-keyer-part-3/ http://www.pa1jim.nl/2009/06/voice-keyer-part-3/#comments Tue, 30 Jun 2009 13:10:12 +0000 PA1JIM http://www.pa1jim.nl/?p=359 Continue reading →]]> Okay, it took a while but I’ve finished the voice keyer project! The last article about this voice keyer I’d receive the wrong package. The second time I did receive the correct PCB but the programmed GAL-chip was a 20-pins one instead of a 16-pins. After receiving the correct GAL-chip there was another problem. When I put on the keyer, all the leds where on and when I pushed one of the buttons, the led went out. Exactly the other way around from what should be… Another good look at the circuit learned me that you never have to trust a part list on its own. Always double-check with the circuit before ordering parts. The 5 transistors in this keyer should be (according to the part list) the NPN BC547. But at the end the circuit told me otherwise: 4 of them should have been a PNP BC557.
So after re-ordering the new transistors, the keyer works great! The sound is good, the handling is just perfect! I’m really happy with the result. I don’t know if the casing in the pictures will be the final one. Maybe I build or buy something nicer. But for now it’s fine! The next contest I can relax and listen!

It is a really simple and cheap to build voice keyer. For something around 40 euros you’ve got it up and running (of course without casing).

I will write an article about this building project for our club site soon. There will be circuits and PCB-layouts attached. But first I have to get permission from the original designer. Will announce here when it’s published.
Voicekeyer printvoice keyer frontvoice keyer operational

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