Hallo all, some time ago we did an experiment with the new KTH-SDR receiver and POWER-SDR receiving APT.
We where able receiving APT pictures with a bad antenna. Some results can be found in the PE1KTH files from the Softrock40 group. The conclusion is that with an optimal antenna and a simplified SDR direct conversion receiver APT reception is possible.
Now we come out with more info of the new all mode receiver.
An NEW novel wideband KTH-SDR direct conversion I & Q receiver info is now available. The receiver front-end is based on de the LINEAR I & Q demodulator LT5517. Frequency range from 3.5 MHz till 450 MHz.
The receiver is built modular with the Si570 LVDS synthesizer, 7 HF sub octave band pass and one 50 MHz RF filter. A VHF/UHF module for 137-145 MHz and 70 cm band is under construction.
Features; USB tuning, LCD display, Encoder tuning, Frequency Memory, Tuning step and RF Attenuator. The modules are placed on a EURO card motherboard in the Aluminum housing. The receiver can work with POWER-SDR and Rocky 3.6.
The info can be found on PA0RWE site in English and in Dutch 2 full-published articles in the Dutch QRP club newsletter (nieuwsbrief) number 128 and 131 with schematics
software description and photos.
73' Joris PE1KTH