Archive for May 1st, 2010


1 May, 2010

From Graham, G0NBD:

First qso on 500 kHz using ros , G0NBD and G4WGT , initially using 500/16 and then eme , reducing tx power , the level that the eme mode started to fail was in technical terms ‘just silly’ reducing the tx to 3 watts carrier power then via a 20 dB attenuator down to 30 mW to a 35 ft top loaded Ae that needs round 50/75 watts to produce 100 mW erp , ie approx 500 : 1 reduction …….. reception 30 miles away by a similar Ae , then produced 100 % copy , depending on local noise level …

Later in the evening , M0BMU called G0NBD at 500/8 , a range of 200 miles , then follower at 100% qso over some 30 mins ending round 0010 local time , one final tx at 500/16 was also 100% decode , even in deep QSO , to the point of no audio from the speaker, the mode remained in lock and kept printing , each station running 100 watts.

Outstanding mode Jose !

73 – G ..

Congratulations for the experiments, Graham, although ROS EME was not designed for HF. ROS1/500 would be a better option in that case.

Which is the wideband avaiable for a 500Khz Band Rig? Would be possible use 2250 Hz in the 500Khz band?