My QO-100 Station

  • Here my just ready built Transverter (SG Labs) for robust portable use together with FT897. The portable Dualband Antenne needs to be developed now. This will be used out of the Motor Caravan in summer. The output Power can be regulated to adapt to the portable Situation. The small old style instrument shows the output power (forward or return) switchable. 73 de Kai

  • Here my just ready built Transverter (SG Labs) for robust portable use together with FT897. The portable Dualband Antenne needs to be developed now. This will be used out of the Motor Caravan in summer. The output Power can be regulated to adapt to the portable Situation. The small old style instrument shows the output power (forward or return) switchable. 73 de Kai

    Nice setup.

  • My RX setup is finally running since today.

    I am using a 1,2m dish with an Octagon LNB. The LNB is modified for feeding in the LO.

    I have used different OCXOs und GPSDOs von China. But the Leo Bodnar GPSDO is much cleaner. The QRG of the LO is 27.85015 MHz in order to have almost the same kHZ digits on 432.xxx MHz. I have used two low path filters from WIMO do clean the signal. I have now a clean Sinus wave.

    The chineese devices are generating harmonics even with a 30 MHz low path filter.


    For transmitting I am using a 1m mesh dish from RF Hamdesign with original helix feed.

    I will transmit on 23cm to feed the BU500. After the BU500 I have a 50 MHz Bandpass filter for 2.4 GHz to eliminate the stron IF from the BU500.

    As PA I have a modified 2.1 GHz 120Watt PA. Which is too much power. I have to play with a chain of attenuators to reduce the power.


    The TX path will take another 4 Weeks I guess. I have too less time for ham radio..

    Martin

  • What is the reason to use the filter? You want a sine wave as a reference, but why? I used the Leo Bodnar mini GPSDO with and without a filter. No difference in receiver performance.

    Hello Patrick,


    yes, I want a sine wave. Before I had used a chinese GPSDO device and this generated multiple spectras. I am also using the Leo Bodnar device now. I haven't test it without the filter.

  • I'm finally on the air with QO-100! The receiving part was already active, I was just waiting for the 2.4GHz transceiver and PA to arrive from SG Labs, and they finally did.


    The RX part is composed by the LNB voltage generator, a raspberry pi 3 and a RTL based SDR; the LNB voltage generator is controlled by the raspberry, as well as the power to the TX part and to the rotator of the TX dish (controlled by a k3ng rotator controller on an Arduino Nano). Antenna is 80cm offset dish and the feed an Octagon PLL LNB, no clock injection.


    The TX part is made of SG Labs transverter and a buck step down converter from 24V (from the RX box) to 13.8V. Dish is prime focus 1m and feed is an old AO40 self made patch antenna. In the end PA has not been used as the bare output of the transverter (about 1w at the patch antenna after 2 meters of RG58) is enough to bring me on the bird. A 20w PE1RKI isolator has been used at the output of the transverter to make sure nothing gets fried in case of bad matching with the antenna.

    Here there are a few pics of the TX and RX chain; now that the work is done I can relax on an armchair and have a little fun on this beautiful satellite. See you on QO100!


    73 de iz2eeq

  • My portable setup at the airport festival "100 years first flight F13" in Dessau - JO61CU

    RX: Wlan Dish 60 X 90 cm, SG-Lab + PA ca. 10W

    RX: 60cm, Octagon Twin LNB, GPSDO - 27MHz + 594MHz, Out 145,.....MHz
    TRX: IC 910 2m / 70cm - full duplex

    Signal and band control with RSP2 + SDRuno

       


    VY 73 Jürgen