Infra red version Ronja by -=RYS=- (Martin Patera, OK1MJO) =========================================================== 1) In RX part change rx photodiode on type SFH2030F (or other infra red photodiode). 2) In TX part change tx diode HPWT LED on type HSDL-4230. 3) In TX part change R11 8R2 on 4R7. ( ! I = 140-160mA ) 4) In TX part add one 74HC04 (4x IC). 5) In TX part dimension U4 for 1A.