Re: CRICKETEERS - WHY CHOOSE? DO BOTH !
On 12/04/17 20:51, Gary Lyons gary.w0gx@... [4sqrp] wrote:
Well done Tom! Love it when simple tweaks are shared. Thanks.For anyone interested in how I connected the PNP transistor to use an electronic keyer with the Cricket, I've uploaded the modified schematic. This schematic also includes the mods I did to make the Cricket accept other crystals. It can be found here: https://www.dropbox.com/s/q5lxnwg0o183p1z/Cricket%20schematic.jpg?dl=0
An external keyer or straight key can be connected to the jack. The red LED will light upon keydown either with a key or keyer connected to the jack or the on-board key. I used a 2N5416 transistor but probably any high-current PNP can be used. I don't know if something like a 3906 would provide enough current or not or get too hot, but the 5416 doesn't even get warm on keydown.
You can see the key jack and the two LED's off to the right side of the board in this picture: https://www.dropbox.com/s/hik3ktz4jrsv1cx/Cricket%202.jpg?dl=0 The PNP transistor is attached to the bottom of the board as well as the current limiting resistors for the LED's.
You can also see that the other mods I performed was to mount the headphone and antenna jacks vertically. This was done in order to fit the Cricket board into the box I bought for it. I merely removed the supplied BNC and drilled a large hole for the panel mount BNC, then soldered a wire from it to C5. The headphone jack I simply bent a couple of the leads down to mount it vertically, then a wire from the center pin on the jack to its connection on the board. I secured it with epoxy to the board to relieve strain on the solder connections.
Tom Sevart N2UHC
St. Paul, KS