21 Oct 2012

Simple 10m AM transceiver?

Yesterday, someone suggested that I build a simple 10m AM rig. Now clearly the best option would be a DSB transceiver for which I have many of the ideas clear in my head and implemented in my WISPY transceiver for WSPR.

However, I think it would be fun to make a 10m version of my Fredbox and Sixbox QRP AM transceivers. These are to be described in an article in Practical Wireless. For local nattering I think more output is needed on 10m, probably 1-2W AM. A low level series modulator followed by a single stage linear amplifier is a simple way to go on TX. For receive, a super-regen receiver would be fine for local use when the band is not busy. This is 75% of the time at least and almost 100% of the time in the evenings, most times of the year. It would be unsuitable when the band is very active, as currently during the day. A better AM receiver could be built, but nothing beats a super-regen for elegant simplicity, as long as it has an RF amp to isolate it from the antenna.

Maybe this is a quick project for a few autumn afternoons. A few watts of AM on 10m should span several miles locally with a vertical or a dipole.

1 comment:

Kenneth Finnegan said...

I just wanted to let you know that I've really enjoyed reading about the 2m and 6m AM boxes, so another project of that scope would have at least one interested reader.

I started working on my own 2m fredbox this weekend as my first RF project. I've currently got the first multiplier stage (24MHz to 72MHz) working, so I'm pretty excited. Thanks for all your useful information.