[amsat-bb] RTSystems has Software for Kenwood TH-D74a

Patrick STODDARD (WD9EWK/VA7EWK) amsat-bb at wd9ewk.net
Sun Dec 4 18:18:52 UTC 2016

Hi Jeff!

With the TH-D74, you get new features for receive filters. For SSB,
the high-cut value has possible options between 2.2 to 3.0 kHz. For CW
bandwidth, it can be specified values between 0.3 and 2.0 kHz. On
AM, the high-cut value can be between 3.0 and 7.5 kHz. This is, I
think, the sort of filtering that the TH-F6A sorely lacked.
Having this filtering makes the TH-D74's all-mode receiver work
reasonably well, especially as an SSB receiver for satellite
downlinks. I am comfortable with using my TH-D74A as an SSB
receiver in place of one of my FT-817NDs or an SDR receiver.

The TH-D74 also has an audio recording function, when a microSD
card is plugged into the radio. I used that to make recordings
of different passes I worked (FM, SSB, packet), and also testing
a Bluetooth headset with this radio. I posted those recordings
in the "TH-D74A" folder at http://dropbox.wd9ewk.net/ . If you want
to hear recordings from SSB satellites specifically, please
let me know and I can get you those file names.

I think Kenwood missed the mark a bit with this radio, not designing
it to have the cross-band full-duplex capability of the TH-D72
and TH-D7. Since the TH-D74A also operates on the 222 MHz band, it
is possible that Kenwood's engineers based the TH-D74 on the design
of the TH-F6A, but with lots of improvements and new features
that weren't possible with the older radio.


Twitter: @WD9EWK

On Sun, Dec 4, 2016 at 5:55 PM, Jeff <kb2m at comcast.net> wrote:

> Does it still have the 6k  something + wide SSB frontend like  the 10+
> year old TH-F6a? I read Patrick's post about it and I don't remember any
> Kenwood rep at Dayton say it would do full duplex. I think Kenwood really
> missed the boat on this one.
> 73 Jeff kb2m

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