In the summer of 2016 MSK144 was introduced and it developped meanwhile in a widely used mode for meteorscatter. An effective transmision rate of 250 characters per minute, a bandwidth efficient modulation, a cutting-edge forward error correction and the ability to decodes signals as low as -8 dB in a 2500 Hz bandwith should give you more decodes than the older FSK441 protocol.
However, the introduction of the MSK144 protocol has also caused uncertainties. Frequency, timing, which period to transmit, no decodes... all questions you can see on the various chats with all kinds of different answers.
As the 144 MHz Meteorscatter Sprint Contest 2020 is near, we would like to say a few lines about using MSK144.
- MSK144 is for meteorscatter contacts. Do not call stations via tropo; usually this means distances below 800 km.
- The center calling frequency for MSK144 in Europe is 144.360 MHz.
- On the calling frequency we use ONLY 30 second periods. By local agreement all stations in the Netherlands, Belgium, Germany, Luxemburg, Denmark and the upper half of France (line Brest - Tours - Dijon) will ALWAYS transmit second period. Using 15 second period in the wrong timeframe will cause mutual inteference, loss of signals and above all bickering and annoyance. Forget all the old stuff written about timing of meteorscatter.
- Due to the forward error correction, MSK144 will give you a full decoded line or nothing. Meteorreflections are proportional to the inverse square of the operating frequency and therefore a 144 MHz ping will last 1/8 as long as those on 50 MHz. In MSK144 most of the transmitted frame must be received to decode the message, so pings less then 70 ms, very common on 144 MHz, will NOT decode. When you face such conditions, trying FSK441 might be a better option as it will give you also decodes on pings smaller then 70 ms. Maybe you will need to puzzle a bit more but at the end you might succeed.
|Sept. ε-Perseids (5)||2020-09-09|
|Dayt. Sextantids (5)||2020-09-27|
Meteor Scatter: August 2020
Now it's the time for one of the most popular meteor showers: the Perseids. According to IMO, the maximum in 2020 is expected to occur on August 12, most likely between 13h and 16h UT, with ZHR=110 hr-1. Read more about that (together wi ... more
Latest AU - 2020-04-20
Feel free to join the public group chat of MMMonVHF at Telegram Messenger.
In addition to our MMMonVHF_bot, we set-up this open chat for exchange, requests and discussion.
If you are already at Telegram, you may join the group chat by clicking https://t.me/mmmonvhf (or search for "MMMonVHF" within the platform).
We hope you will enjoy and support this platform.
We're happy to announce the launch of our news bot on the encrypted messaging platform Telegram.
If you are already on Telegram, you can check out the bot by following this link (or search for "MMMonVHF_bot" within the platform).
The bot instantly delivers you all updates around MMMonVHF, after just sending once the /start command. Several additional commands are available. Just type /help to get an overview.
The bot is still in development, so changes and additional commands may arrive.
Any feedback is welcome!