Donnerstag, 30. Juni 2016
Using the Icom IC-7300 for MF (472 kHz)
With the TX-Mod described here, the IC-7300 is capable of transmitting down to 100 kHz. The output on 100 kHz is too small to be useful. But on 472 kHz the TX can deliver up to 20W.
However, the PA and LPF are not designed for this frequency and it is wise to reduce the power in order to play safe. With the power set to 0% the TX puts still out about 200mW. This is enough to drive an external PA like the one I’ve described here.
Due to the lack of an appropriate LPF, the harmonics are strong, as you may see in the second picture (30dB Att.).
But after the filtering in the proposed external PA, it will be sufficient clean (picture 3, 50dB Att.). 200mW will be enough to deliver a 100W signal. With this, CW and digital modes are at your fingertips.
For a first try without the external PA, you may go to 10% of the power setting. Then the Icom will put out 4 to 5W. I would not encourage a further increase, as compression sets in and you may endanger the PA in your IC-7300.
Of course an appropriate and tuned antenna is necessary. The ATU does not tune in the 630m Band.
First picture: Nordkapp 71°10′21′′
Eingestellt von Anton's Funkperlen um 16:30