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AE5ME > ARES 29.03.16 04:57l 20 Lines 5662 Bytes #999 (0) @ WW
BID : 4272B8Z2DMG4
Read: GUEST
Subj: Digital Emergency Communications Series by AD5XJ (SAT
Path: IW8PGT<F1OYP<F4DUR<F3KT<F1OYP<7M3TJZ<HG8LXL<N0KFQ<AE5ME
Sent: 160329/0209Z 34479@AE5ME.#NEOK.OK.USA.NOAM BPQ1.4.64
The waterfall and digiscope will appear as:
This display indicates an and extremely linear detected signal (as indicated by the digiscope on the right) with little noise shown on the waterfall.
The text displayed in the status area is the secondary text being sent by the transmitting station. When the keyboard buffer is empty the Thor modem transmits text from the secondary text buffer. Your secondary text buffer can be edited on the Thor configuration tab.
Transmit Image
Transmitting an image in Thor is initiated by selecting the "Send image" menu item from the pop up Tx menu. Right click on the Tx panel. This selection opens up the Send Image dialog.
The Send Image Dialog is shown with a 160x120 color image loaded and ready to transmit.
Transmission begins when you press the "Xmt" button. fldigi will insert the text preamble and immediately begin the image transmission. fldigi returns to the receive mode when the image transmission is completed.
Receive Image
Reception is completely automatic. The decoder will identify the picture start, and record the picture. In doing so, it automatically opens a separate "Thor Rx Image" dialog.
OLIVIA
In an article that appeared in QST Dec. 2008 the author Gary Robinson, W8ROL describes OLIVIA mode this way:
Olivia mode can be set to various formats that are labeled using the particular format’s bandwidth and number of
tones. Bandwidths of 125, 250, 500, 1000 and 2000 Hz are typical. The number of tones can be set anywhere from 4 to 256 depending upon the propagation conditions. Different combinations of tones and bandwidths provide for slower or faster transmission rates. Commonly used formats are 125/4 (125 Hz bandwidth using 4 tones), 250/8, 500/16, 500/8, 500/16, 1000/32. The 500/8 format seems most popular at this moment, though I have had several QSOs on the 125/4 and 250/8. The 1000/32 format seems to be popular on 20 meters.
Each of the Olivia formats has advantages and disadvantages. Obviously, the bandwidth differences make the more narrow formats attractive because they will fit in available open spectrum space more easily. They also will likely get through slightly better since all the power of the transmitted signal is concentrated in a smaller bandwidth — much the way CW gets through better than wide phone signals.
The speed of Olivia is an issue also. Olivia is generally not as fast as PSK31 or MFSK16. Olivia 500/16 sends text at approximately 20 wpm. The 500/8 format speeds that up to nearly 30 wpm. Fewer tones results in more speed while less bandwidth results in slower speed. Olivia 1000/8 and 2000/8 are often used by Military Affiliate Radio System (MARS) traffic nets because these formats are fairly fast, accurate and get through when the MT63 mode (a digital mode using 64 tones phase shift keyed in a 1 kHz bandwidth) fails. Most of this information and more pertaining to Olivia are available at the HFLink and DXZone Web sites.
Many hams find Olivia slower than they like and prefer to use other modes, while many others find the accuracy and ability to get through an acceptable trade off. Also, many of us, including myself, are not fast typists and actually find "slower" to be a positive attribute and allows for more comfortable overall operation.
Another advantage to the mode is that it’s not quite as critical for it to be tuned exactly on frequency as it is with PSK, MFSK and many other modes. If you click on the waterfall with your mouse and the indicator doesn’t get exactly on the signal it may still decode properly. Most implementations of Olivia are set to search for signals to either side of your center frequency by a fixed percentage of your signal’s width. The W1HKJ documentation describes OLIVIA this way:
These [OLIVIA sub-modes] are unconnected, simplex chat modes with full time Forward Error Correction. Olivia is a very robust mode with low error rates, but the penalty can be an annoyingly slow transfer of information. If you are a one finger typist then Olivia is your cup of tea. The tones are spaced the same as the baud rate, for example 31.25 Hz for the default baud rates. The default calling mode is 32-1000. It has the following appearance on fldigi's waterfall: When you call CQ on this mode be patient and wait at least 45-60 seconds before you put out another call. When the other person who hears your CQ clicks on the waterfall it may take 4-20 seconds or even longer before they might actually start decoding your signal. That varies a lot depending on the software they are using AND value they have their Sync Integration Period set to. The Sync Integration Period setting determines how "deep" the Olivia decoding algorithm searches in the noise to get the signal. A higher settings takes longer BUT usually decodes with more accuracy - at least to a point. However, a higher setting (since it does more work and takes longer) will increase the delay factor. So, when you finish your CQ and your transmitter switches to receive - the station listening to you (depending on his Sync Integration Periods setting) MAY NOT finish decoding your CQ for another 4-20 seconds. The same applies during a QSO when you pass it back to the other guy for his turn – be patient if he doesn't come back right away because his software may still be decoding your signal long after you stopped transmitting.
It DOES NOT PAY to be impatient on this mode and send SHORT CQ's or NOT wait at least 45-60 seconds between CQ's. Generally a 2x2 CQ sent at least 2 or 3 times is going to work much better for you than a short one. . . . FLDIGI can operate on the following Olivia modes without special setup by the operator:
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