This is the 300Hz datamode filter setting on the rig with IF Shift set at its centre setting. You can get it to filter all audio except for a narrow band 1400 to 1700 Hz wide on the narrowest setting. I also use the Width filter to remove stations from either side. It is very narrow and you are able to use it to remove a strong station transmitting a few Hz bandwidth especially PSK-31. The FT-450 has a tunable notch filter that is easier to control with HRD than using the controls on the rig itself. I normally make use of the rigs own filters to tune out QRM. The ways of getting rid of QRM are very wide ranging and easy to do.
If somebody is transmitting on SSB a few KHz up then engage your IF Shift. When somebody is tuning up close to your listening frequency engage your tunable notch filter. From very early days it has been possible to engage IF filters, notch filters and such like on communications equipment. The two useful filters on the FT-450D highlighted in yellow This can sometimes result in swamping the signal coming from your contact. That station probably can't hear your contact so doesn't know that it is generating QRM. This works well 99% of the time but you do get occasions in the middle of a QSO when a very strong station starts transmitting in an adjacent audio frequency. The software, in my case Ham Radio Deluxe running the DM780 module, then uses software filters to narrow reception down to whatever audio frequency you have selected in the waterfall. This is the correct setting for operating RTTY FSK in DM780.The standard way of operating a datamode such as PSK-31 is to leave the filter width as wide as you can and tune to the operating frequency. Back on the Main window click on “Reverse”.RTTY tab, check FSK Keying Enable, the correct COM Port for keying (as above in CW) and tick the radio dial “Rigblaster PRO (TX, DTR), Icom (DTR) etc….
0 kommentar(er)
