3.4 GHz DATV

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As the UK band has recently been reduced to 10 MHz (3400 to 3410MHz) it is only possible to run DATV and there is currently very little activity in the UK apart from repeater outputs.

Reports from the repeaters on 3.4GHz suggests it is very low noise spectrum and actually performs as well if not better than 2.3GHz.

There is (or was) a lot of surplus transmit (and receive) equipment on the surplus market, mainly from the failed Ionica broadband wireless system, and it is a very easy band to get on to, both for Tx and Rx.

Receiving 3.4 Ghz DATV

9cms rx.JPG

However it is actually a very easy band to receive DATV on using C band satellite LNBs feeding directly in to a free to air satellite receiver or MiniTiouner

A lot of people use the Titanium PLL LNB available from ebay. You can either use the basic LNB or mount it on a Sky mini dish to give more gain.

G8GTZ antennaes.jpg

Transmitting 3.4GHz DATV

  • Airspan AS4000

G6gvi9cm.jpg

The Airspan AS4000 is an outdoor consumer unit operating in duplex mode (Tx and Rx) on 3.4 GHz - it needs DC supply, transmit IF and reference oscillator up the co-ax and sends rx IF down.

The unit IF is at 820 MHz and G6GVI and M0DTS have both modified the local oscillator by changing the reference oscillator and reprogramming the PIC to provide an IF at 1296.

However, it is now possible to just use the ADF4351 controlled by Ron G7DOE's simple controller to provide an LO of 2970, which provides an IF at 432 MHz for Narrow Band and DATV use.

Link to G6GVI page

Link to M0DTS page

  • Ionica PA

Surplus units which require no modification to produce 15 watts NB or 5 watts DATV when driven by the AS4000

Link to Page listing how to use the Ionica PA