One of the things that I thought of as soon as the RBN-SOTAwatch link was set up was its use for QRPp operation (power levels < 1 watt) using simple crystal controlled equipment. The RBN frees you up to move away from the busy QRP frequencies. This is also ideal for my development of a system to carry on my road bike to allow SOTA operations.
The first stage has been to build a radio and I looked no further than the tried and tested Rockmite. I went for the 20m version and selected 14.050MHz. I also splashed out on the fancy machined Mity Box. I built the radio this evening and on powering it up I immediately heard signals. I put out a couple of quick CQs to see if the RBN saw me and was unexpectedly rewarded with a call from Alex RD8W in Asiatic Russia. We had a nice chat and so the radio looks good to go.
To keep things very small and light I tried out a Pico Paddle for the first time. That also worked well.
I am intending using 3 x 18650 cells for the power supply.
I have a few ideas for an antenna but that will take some more development.
In reply to G3CWI:
Hi Richard,
a Photo would be nice if you have time
I like these qrpp rigs !
i also will build a ultra small smd 40m trx with abt. 500mw out…
A Mity box too, how posh! I notice some RBN spots for you this evening on 14.048, so it looks like it’s bang on the usual 2kHz lower than crystal frequency.
The Mity box is a tough little number so I would think it will be ideal for the bike.
Interesting comparing the snr figures; there doesn’t seem to be much difference between what’s reported on this and that side of the ocean…
I’ve tended to assume that if a station over there is sptted by a skimmer over there which reports a low single digit snr then I might as well not bother listening for it. I probably ought to review that assumption.
…unless, perhaps, the snr values are a bit approximate, of course?
73, Rick M0LEP (who built a RockMite on 14.06? but has never yet used it.)
73, Rick M0LEP (who built a RockMite on 14.06? but has never yet used
it.)
Get it on the air Rick! RockMites are great fun, they are so simple but very effective. The feeling from working DX with something you’ve built yourself is fantastic.
If your RockMite is using 14.060MHz crystals your TX frequency will be around 14.058MHz. Note that the RX offset amount is different on each ‘channel’. If your Rig uses the MVAM109 varicap for D6, I’d suggest changing D5 to a 5V1 zener, this should bring the TX/RX shift to a nominal 700Hz.
