When watching a documentary today I noticed that the makers used the very known rtty sound when they are talking over wireless communication. I remember that in the James Bond films of the 60's and probably the 70's also they use the same sound. I guess it is a 75 or 100 baud rtty sound. Even in modern shows or films it is used. Who has a better and more up to date sound that can be used ?
Archive for the Digital Mode Category
My top 5 of my best dx using wspr. On 20m the antenna is a half wave vertical. On 80/40 and 30m I used the Diamond W735 with an extra dipole for 30m. This antenna hangs just 2 meter above the lawn. (more…)
05 02 2009
Ham radio operators interested digital modes will often use these computer interfaces to automate CW contacts (send morse code from the PC), use the PC soundcard for RTTY and control push-to-talk functions among other things. Many of the PTT interface drawings found on the net suffer the same problem. Well it is not really a problem.
A friend of me asked if I could detect some WSPR signals on 20m. He has been monitoring it a while without any activity. I also read the comments of G4ILO on the WSPRnet.org site : http://wsprnet.org/drupal/node/384 I must admit that I was also stuck on 30m. He made a statement and yesterday I had a day off. A whole day of listening later this is what passed my screen :
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az 2009-01-21 10:48 EA1FAQ 14.097137 -24 0 IN71op 0.5 ON3JT JO21fe 1274 30 2009-01-21 09:58 VK6BN 14.097091 -23 -1 OF88ac 10 ON3JT JO21fe 14167 313Not much. Hey guys, if you want that propagation monitoring works, we need to activite all bands.
Tonight I used WSPR again to see the activity on 30m. Now I received about 7 stations from the USA, Hungary, Spain, Switzerland, UK and the Czech republic. After a few hours I ticked the 20% T/R option. This switches the transceiver on for 20% of the time and the remaining 80% listening. And yes, my signal gets out. Using only 2 watts my signal is picked up by VK6KHD, Nigel in Australia. My first. That is about 14190 km or 7095 km per watt or very very far from my qth 🙂
16 12 2008
Last saturday night my computer has been running all night long the WSPR (whisper) software from ..... to see if I could receive that mode too. My wife had the night shift in the hospital and could not argue that the computer is making too much noise in the bedroom 🙂 That is the downside of having the shack in the bedroom. I set the receiver to 10.138.7 in the 30m band and went to bed. (more…)
13 11 2008
After reading this site : http://paginas.terra.com.br/lazer/py4zbz/hamdream/rxdrm.htm I modified my Icom IC725 with a similar capacitor. It worked more or less. Switching to the CW-N mode on my trx and decoding with Dream I could listen to some DRM radiostations. At that time the only antenne I could use was a magnetic loop, mounted near the window. Not the setup that everyone dreams of 🙂 (more…)