More updates to the WSJT-X User Guide.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7995 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
| @ -18,16 +18,23 @@ double-clicking on decoded text or a signal in the waterfall.  They | ||||
| can also be adjusted using the spinner controls. | ||||
| 
 | ||||
| * You can force Tx frequency to the current Rx frequency by clicking | ||||
| the *Tx<-Rx* button, and vice-versa for *Rx<-Tx*.  Check the box *Lock | ||||
| Tx=Rx* to make the frequencies always track one another.  The | ||||
| on-the-air frequency of your lowest JT9 or JT65 tone is the sum of | ||||
| dial frequency and audio Tx frequency. | ||||
| the *Tx<-Rx* button, and vice-versa for *Rx<-Tx*.  The on-the-air | ||||
| frequency of your lowest JT9 or JT65 tone is the sum of dial frequency | ||||
| and audio Tx frequency. | ||||
| 
 | ||||
| * Check the box *Lock Tx=Rx* to make the frequencies always track one | ||||
| another. | ||||
| 
 | ||||
| TIP: In general we do not recommend using *Lock Tx=Rx* since it | ||||
| encourages poor radio etiquette when running a frequency.  With *Lock | ||||
| Tx=Rx* checked, your own Tx frequency will move around following your | ||||
| encourages poor radio etiquette when running a frequency.  With this | ||||
| box checked, your own Tx frequency will move around following your | ||||
| callers. | ||||
| 
 | ||||
| * For modes lacking a multi-decode feature, or when *Enable | ||||
| VHF/UHF/Microwave features* has been checked on the *Settings -> | ||||
| General* tab, the *F Tol* control sets a frequency toilerance range | ||||
| over which decoding will be attempted, centered on the Rx frequency. | ||||
| 
 | ||||
| * The *Report* control lets you change a signal report that has been | ||||
| inserted automatically. Typical reports for the various modes fall in | ||||
| the range –30 to +20 dB.  Remember that JT65 reports saturate at an | ||||
| @ -37,13 +44,36 @@ TIP: Consider reducing power if your QSO partner reports your | ||||
| signal above -5 dB in one of the _WSJT-X_ slow modes.  These are | ||||
| supposed to be weak signal modes! | ||||
| 
 | ||||
| * With *Split operation* activated on the *Settings -> Radio* tab, you | ||||
| can activate the spinner control *Tx CQ nnn* by checking the box to | ||||
| its right.  The program will then generate something like `CQ nnn | ||||
| K1ABC FN42` for your CQ message, where `nnn` is the kHz portion of | ||||
| your current operating frequency.  Your CQ message *Tx6* will then be | ||||
| transmitted at the calling frequency selected in the *Tx CQ nnn* spinner | ||||
| control.  All other messages will be transmitted at your current | ||||
| operating frequency.  On reception, when you double-click on a message | ||||
| like `CQ nnn K1ABC FN42` your rig will QSY to the specified frequency | ||||
| so you can call the station at his specified response frequency. | ||||
| * In some circumstances, especially on VHF and higher bands, you can | ||||
| select a supported submode of the active mode by using the *Submode* | ||||
| control.  The *Sync* control sets a minimum threshold for establishing | ||||
| time and frequency synchronization with a received signal. | ||||
| 
 | ||||
| * Spinner control *T/R xx s* sets sequence lengths for transmission | ||||
| and reception in ISCAT, MSK144, and the fast JT9 modes. | ||||
| 
 | ||||
| * With *Split operation* activated on the *Settings -> Radio* tab, in | ||||
| MSK144 and the fast JT9 submodes you can activate the spinner control | ||||
| *Tx CQ nnn* by checking the box to its right.  The program will then | ||||
| generate something like `CQ nnn K1ABC FN42` for your CQ message, where | ||||
| `nnn` is the kHz portion of your current operating frequency.  Your CQ | ||||
| message *Tx6* will then be transmitted at the calling frequency | ||||
| selected in the *Tx CQ nnn* spinner control.  All other messages will | ||||
| be transmitted at your current operating frequency.  On reception, | ||||
| when you double-click on a message like `CQ nnn K1ABC FN42` your rig | ||||
| will QSY to the specified frequency so you can call the station at his | ||||
| specified response frequency. | ||||
| 
 | ||||
| * Checkboxes at bottom center of the main window control special | ||||
| features for particular operating modes: | ||||
| 
 | ||||
| ** *Sh* enables shorthand messages in JT4, JT65, and MSK144 modes | ||||
| 
 | ||||
| ** *Fast* enables fast JT9 submodes | ||||
| 
 | ||||
| ** *Auto Seq* enables auto-sequencing of Tx messages | ||||
| 
 | ||||
| ** *Call 1st* enables automatic response to the first decoded | ||||
| responder to your CQ | ||||
| 
 | ||||
| ** *Tx6* toggles between two types of shorthand messages in JT4 mode | ||||
| @ -18,10 +18,9 @@ recognized ADIF format, for example 630m, 20m, or 70cm.  The band-name | ||||
| format works only if a working frequency has been set for that band | ||||
| and mode, in which case the first such match is selected. | ||||
| 
 | ||||
| TIP: You can also enter a frequency increment in kHz above the | ||||
| currently displayed integer MHz. For example, if the displayed | ||||
| frequency is 10,368.100, enter `165k` (don't forget the `k`!) to QSY | ||||
| to 10,368.165. | ||||
| * You can also enter a frequency increment in kHz above the currently | ||||
| displayed integer MHz. For example, if the displayed frequency is | ||||
| 10,368.100, enter `165k` (don't forget the `k`!) to QSY to 10,368.165. | ||||
| 
 | ||||
| * A small colored circle appears in green if the CAT control is | ||||
| activated and functional.  The green circle contains the character S | ||||
| @ -34,10 +33,6 @@ split transmit frequency. When using _WSJT-X_ with such radios you | ||||
| should not change the current VFO, split status or dial frequency | ||||
| using controls on the radio. | ||||
| 
 | ||||
| * The slider adjacent to the level meter can be used to adjust the | ||||
| signal level sent to the Fast Graph.  If *Flatten* is not checked, | ||||
| the same is true for the Wide Graph. | ||||
| 
 | ||||
| * If *DX Grid* contains a valid Maidenhead locator, the corresponding | ||||
| great-circle azimuth and distance from your location are displayed. | ||||
| 
 | ||||
|  | ||||
| Before Width: | Height: | Size: 37 KiB After Width: | Height: | Size: 34 KiB | 
| Before Width: | Height: | Size: 234 KiB After Width: | Height: | Size: 151 KiB | 
| Before Width: | Height: | Size: 86 KiB After Width: | Height: | Size: 86 KiB | 
| Before Width: | Height: | Size: 6.2 KiB After Width: | Height: | Size: 5.8 KiB | 
| @ -1,3 +1,55 @@ | ||||
| === AP Decoding | ||||
| 
 | ||||
| With the QRA64 decoder Nico Palermo, IV3NWV, introduced a technique | ||||
| for decoding with the aid of information that naturally accumulates | ||||
| during a minimal QSO.  This _a priori_ (AP) information can be | ||||
| used to increase the sensitivity of the decoder. | ||||
| 
 | ||||
| When an operator decides to answer a CQ, he already knows his own | ||||
| callsign and that of his potential QSO partner.  He therefore knows | ||||
| what to expect for at least 56 of the 72 message bits in a | ||||
| standard-format response to his call.  The _WSJT-X_ decoders for QRA64 | ||||
| and FT8 can use these AP bits to decode messages containing them with | ||||
| higher sensitivity than otherwise possible. | ||||
| 
 | ||||
| We have implemented AP decoding in slightly different ways in QRA64 | ||||
| and FT8.  To provide some explicit examples for users, we provide here | ||||
| a brief description of the FT8 behavior. | ||||
| 
 | ||||
| The FT8 decoder always tries first to decode a signal without using | ||||
| any AP information. If this attempt fails, and if *Enable AP* is | ||||
| checked on the *Decode* menu, a second attempt hypothesizes that the | ||||
| message contains callsigns MyCall and DxCall. If the QSO has | ||||
| progressed to the point where signal reports have been exchanged, a | ||||
| third attempt hypothesizes that the message contains the known | ||||
| callsigns followed by RRR, RR73, or 73. | ||||
| 
 | ||||
| AP decoding attempts effectively set the AP bits to the hypothesized | ||||
| values, as if they had been received perfectly.  The decoder then | ||||
| proceeds to determine whether the remaining message and parity bits | ||||
| are consistent with the hypothesized AP bits.  If a codeword is found | ||||
| that the decoder judges to have high (but not overwhelmingly high) | ||||
| probability of being correct, a ? character is appended when the | ||||
| decoded message is displayed. | ||||
| 
 | ||||
| Successful AP decodes are always labeled with an end-of-line indicator | ||||
| of the form aP, where P is one of the single-digit AP decoding types | ||||
| listed in Table 1.  For example, an a2 designator says that the | ||||
| successful decode used MyCall as hypothetically known information. | ||||
| 
 | ||||
| [[AP_INFO_TABLE]] | ||||
| .AP information types | ||||
| [width="25%",cols="h10,<m20",frame=topbot,options="header"] | ||||
| |=============================================== | ||||
| |P | Message components | ||||
| |1 | CQ         ?         ?  | ||||
| |2 | MyCall     ?         ?  | ||||
| |3 | MyCall DxCall      ?  | ||||
| |4 | MyCall DxCall RRR | ||||
| |5 | MyCall DxCall 73 | ||||
| |6 | MyCall DxCall RR73 | ||||
| |=============================================== | ||||
| 
 | ||||
| === Decoded Lines | ||||
| 
 | ||||
| Displayed information accompanying decoded messages generally includes UTC, | ||||
| @ -34,24 +86,10 @@ End of line information:: | ||||
|  `f` - Franke-Taylor or Fano algorithm + | ||||
|  `M` - Message length (characters) + | ||||
|  `N` - Number of Rx intervals or frames averaged + | ||||
|  `P` - Number indicating type of AP information (see table below) | ||||
|  `P` - Number indicating type of AP information (Table 1, above) + | ||||
|  `R` - Return code from QRA64 decoder + | ||||
|  `T` - Length of analyzed region (s) | ||||
| 
 | ||||
| [[AP_INFO_TABLE]] | ||||
| .AP information types | ||||
| [width="25%",cols="h10,<m20",frame=topbot,options="header"] | ||||
| |=========================================== | ||||
| |P | Message components | ||||
| |1 | CQ         ?         ?  | ||||
| |2 | DE         ?         ?  | ||||
| |3 | MyCall     ?         ?  | ||||
| |4 | MyCall DxCall      ?  | ||||
| |5 | MyCall DxCall RRR | ||||
| |6 | MyCall DxCall 73 | ||||
| |7 | MyCall DxCall RR73 | ||||
| |8 |   ?       DxCall     ? | ||||
| |=========================================== | ||||
| 
 | ||||
| 
 | ||||
| === Reference Spectrum | ||||
|  | ||||
| @ -212,7 +212,7 @@ longer at distances close to the upper limit.  But with patience, 100 | ||||
| Watts or more, and a single yagi it can usually be done.  The | ||||
| following screen shot shows two 15-second MSK144 transmissions from | ||||
| W5ADD during a 50 MHz QSO with K1JT, at a distance of about 1800 km | ||||
| (1100 mi).  The decoded segments have been encircled on the *Fast | ||||
| (1100 mi).  The decoded segments have been marked on the *Fast | ||||
| Graph* spectral display. | ||||
| 
 | ||||
| image::MSK144.png[align="center",alt="MSK144"] | ||||
|  | ||||