Both the IC-7300 and the IC-9700 have an IF output option. A great feature that enables the receive of all kinds of exotic transmissions. On the IC-7300, Icom pitched this feature at DRM receive. Soon after the IC-7300 launched, it became clear that the IF output bandwidth varies with the receive mode setting, which is illogical (Mr. Spock). For DRM receive, all is fine: set mode to AM, connect something like DREAM to the IF output and listen to PC audio. For CW skimmer, it’s a little more problematic, so maybe Icom only had DRM receive in mind when designing this. It will work, but you have to use a “wide” mode on receive, and use split to send in CW mode. You could select FM, Filter 1, that gives you 16 kHz bandwidth on the IF output (about 4 to 20 kHz, IF out is centered around 12 kHz). But selecting FM mode also fixes AGC at fast mode, which is annoying at times. So best alternative is AM again with 10 kHz filter and your own choice of AGC setting. Note that IF out is not an I/Q style signal, (it’s one signal after all) so you have to configure a program like HDSDR correctly, otherwise you end up with two identical signals on the display (more confusion…).

What has the IC-9700 to do with all this? Well maybe because there’s no DRM on 2m, 70 cm of 23 cm :-) but the IF output on the IC-9700 is set to maximum bandwidth (i.e. about 16 kHz), independent from the receive mode and bandwidth setting. So 9600 baud packet decode should work, as well as verifying the CTCSS tone on FM repeaters, something that is clearly visible in HDSDR.

And it gets better, judging from the various videos and comments on the new IC-705, it’s IF output works the same as on the IC-9700! So no need for split mode anymore when using CW skimmer on HF.

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