28 MHz QRPp QRSS beacon
IW0HK and I0SKK 28 MHz QRPp beacon
The 28 MHz is a QRPp QRSS automatic TX
in a wider QRPp network we are putting together in Italy, with other Italian guys
This little experiment is really a group-friends-work:
basic schematic is from IK1ZYW, Paolo Cravero beacon,
VCXO was from Luca IW1QIF;
tech solutions are from the whole group (I1DFS, IK1ZYW, IW1QIF, IW0HK, and I0SKK)
assembly by And IW0HK (Pic-beacon) and Alex I0SKK (RF hardware)
the aim: study QRPp real possibilities, HF propagations and more....
At February 21st 2007 was added a little Power Amplifier
the schematic is shown here
At May 27th 2007 the power amplifier was modified as in the next schematic (less power, abaout 160 mW output)
the schematic is shown here
SPECS:
Power output : about 22 dBm (16 mW)
Antenna: vertical
Frequency: 28.321.940 kHz
Mod: CW ASK with a 12 wpm and a QRSS3 message
Call: IW0HK
this is the first prototype we made Spectrum Analyzer test (2nd Harmonic 35 dB down)
Some more pics (click to enlarge):
the assembly is more compact a view of the board the 7806 heath sink short view of PA
t
keying and meassge is from the
Pic beacon
chip
by IK2BCP
At June 26 I completed and put on the air a second beacon TX from Rome, called RM2 beacon:
schematic is here (clik to enlarge):
and waveform is here:
page updated 2007 June 26th