Кстати, еще есть IC-7100, вроде тоже с миливаттной передачей от 130 (или 470?) кГц, может у кого есть сейчас такой аппарат, уточните, что там по прд и по прм ниже 1МГц?
француз какой то игрался... не вспомню сейчас позывной.
тут внезапно пишут по поводу иком-7300!
Finally managed to receive 22 sequences from UA3DJG here in West London on an e-field probe + IC7300
Neither the radio nor the local EMI helped.
The IC7300 has a lot of internally generated interference on 2200m so the preamp in the antenna helped lift the signal above the background noise
First decode was at 00.10 when I realised that my version of Rik's software needed to see 400 - 416Hz Hz audio before it would decode.
Final reception was at 04.20 UTC
Thanks for an interesting evening + 2558km
David
G0MRF
Hello David,
Last January I had an Icom IC7300 on loan and have measured the sensitivity at LF:
Mode CW, bandwidth 500 Hz, pre-amp off.
MDS is the same as a 3 dB signal to noise ratio.
Frequency MDS
===============
500 kHz -111 dBm
400 kHz -111 dBm
300 kHz -109 dBm
200 kHz -106 dBm
100 kHz - 97 dBm
To place these figures in persective, I also measured the MDS at 14030 kHz under the same
conditions. I found a MDS of -134 dBm.
If I remember correct, engaging the pre-amplfiers did not improve these figures much.
73,
Roelof Bakker, pa0rdt
Hi Roelof.
Thank you for the sensitivity figures.
I do like the 7300, particularly as it transmits about 8W on 630m. However, when I tune from 1MHz down to 100kHz
you can hear a broad peak of noise just above 300kHz which extends over most of MF/LF.
I suspect this noise leaks into the receive circuits ahead of the preamps. As you say, the internal preamps have no effect on S:N, but a good external preamp
lifts the performance to nicely.
I'll try a comparison with the LCD display 'on' and in 'saver' mode, but it's probably serial data noise or a switched mode supply......
Thank you for all your work on e-field antennas. It's the only way I can hear anything in the city.
73
David
