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Old 13-02-2011, 22:27   #9
mathias
Registered User
 
Join Date: Jul 2003
Posts: 3
Hello,

A big thank you to all for your reports. Without you, the experience wouldn't be so great. We were very surprised to see that you could receive it so far, given the low power and the fact that the antenna is designed for 765kHz. We will now try to analyse and see what we can enhance for the next trial on next Sunday (same times, same frequencies).

We extended a bit the transmission time as we saw that the power amplifier could cope with the DRM signal as it is normally designed for SSB (we first thought that it would overheat). We will probably do the same on next week. We had some linearity problems and had to reduce a bit the power.

You may have had interruptions too because we changed the mode in the middle. We started transmission with 16QAM and so only with audio (no space left for slides) which is the most robust and then switched to 64QAM where you had slides too. Sorry, the time was effectively wrong.

Please don't hesitate at any time to give proposal of what could be enhanced for the next trial.

You can also follow the latest updates on our page: http://www.opendigitalradio.org/inde..._II_in_Sottens

Don't forget to check it before the next trial in case we would have to change something.

Credits also to Yves HB9DTX, Stan from Maxxima, the HB9MM amateur radio club and Swisscom for lending them for a month such a great antenna. At least Sottens will have gone digital before dying. It shows also that DRM transmission can be done with limited equipment (apart from antenna), an interesting thing for local or community radio.

A warm thank you again,

Mathias Coinchon
HB9UFQ
opendigitalradio.org

Last edited by mathias : 13-02-2011 at 22:33.
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