10
« on: March 31, 2016, 1714 UTC »
I'm not native English speaker, so sorry that Undecided
So, I started to plan little beacon, maybe around 10.240 or 9.990.
The biggest problem is power, on winter, the sun is below the horizon about 2 months which makes solar panels useless.
I have only one place, where I'm having an access to a grid power, but there is possibility to get noticed.
I would not run it from my home qth, too many hams near.
That place has a mast, and it's like 190m ASL on top of ski slope, near of little city.
There is also some abandoned houses and farms, but i have not checked to they still have mains connected.
I had a wild idea to wire an Neontube transformer backwards to a mains pole.
Normal grid is 20kV on rural areas, so 20kV 200mA trafo would give some power for TX.
(I'm electrician, so I know what I'm doing there! I have tested that idea, simply feeding one trafo with second one)
Second issue is temperature changes, on winter it's easily -35 degrees of Celcius for weeks and on summer between +25 to +30 degrees of Celsius.
I have built a transmitter, only have to get on attiny13 for keying.
It's simple 7400 chip, two gates as oscillator and two gates running as buffer, simple lpf and two 2n2222 transistors as final stage before main lpf.
5V on pa, and it outputs about 350mW and on 13.8V about 1.1Watts.
Show Posts
