22 Feb 2012

Some 160m AM QRP rig links

Looking around for some ideas for a local natter box, I came across these links for simple AM transmitters and receivers so far:


If you are aware of other, simple, ideas for 160m QRP AM rigs please let me know.  I've still to go through my old SPRATs to see what is there and there have also been some ideas in Practical Wireless.


Ricardo - CT2GQV said...


Out of the junk box I would go for this one: http://www.qsl.net/va3iul/Homebrew_RF_Circuit_Design_Ideas/1.65MHz_AM_QRP_TX.gif
For range (output9, this one look's better but more time to make: http://www.angelfire.com/de/RadioAnarchy/
To place on a mint box, this one: http://www.kdxradio.com/pixie2.html probably with the modulator from this circuit: http://electroschematics.com/2522/am-transmitter-circuit/
...and for the technical challenge of it, this one: http://forum.allaboutcircuits.com/showthread.php?p=426882

Have fun, 73!

IZ8JJI said...

Hi Roger,
the simpler AM TX which I know is made using the well-known Michigan Mighty Mite (see http://www.zianet.com/dhassall/mm.pdf)

I've built an 80m AM transmitter using a carbon microphone (telephone surplus) instead of the key. It works, really! The modulation seems good, I'think the power is very low, but may be enough for your needs. In vase you need more power, try to rise the VCC.
I've used the TX only on the bench, but is very simple and fun to build.

73 de Michele IZ8JJI

IZ8JJI said...

oops....sorry for typing mistakes.

I forgot to tell you that you must omit (short-circuit) the 27 ohm resistance on the emitter line of Q1