Traditionally, whether digital or "over-the-air", signal reports were a traditional part of a QSL. This included the RF signal level received by the radio and the quality of the audio.

People deemed that signal reports could be used to locate an operator, which is process called "triangulation". Unfortunately, "triangulation" is just a sweet myth when it comes to HAM radio because a signal report, when it is received by a station represents the quality of the transmission of the current station as it is received at the other end. However, the transmission-reception cycle embeds so many moving parts that it is more or less impossible to draw a sensible conclusion just for the signal report. First, there are various types of antennas, each having different scatter patterns as well as directions that they are pointed at, then there is the transmit power that is not always sent along with the report, then there are signals bouncing off objects or the atmosphere itself that affect the quality of the signal as it is received; all of these just show that any "triangulation" attempt, even when using, say, three identical reception stations is just a gross estimate. On higher frequency, such as Bluetooth, the same "triangulation" is possible by measuring the signal strength RSSI, but even there, a precise measurement cannot be made.

With that established, signal reports are just a very empirical measure of quality with many HAM operators exchanging them just because they are part of the protocol, not because they are meaningful and preferring to just make sure that the QSO is made.

However, assuming that an operator has a fixed setup; say, an antenna pointing in a specific direction, the usual number of watts used for transmissions, the same transmission level of the audio, then it sometimes becomes interesting to speculate on why the signal quality will differ from the same other station or the same direction, which under ideal circumstances measures the atmospheric propagation. On the other hand, considering a directed antenna such as a Yagi and a receiving station that transmits signal reports, it is definitely possible to tune the antenna by rotating it according to the receiving station but bear in mind that this is mostly a very gross estimate.

Digital HAM does not change the situation too much and signal reports are now directly embedded in the requirements for a successful QSO (without the audio quality report).

Here is a typical FT8 QSL transmission-reception cycle as a QSO is made from a local station whose callsign is LID:

RID LID GRID
LID RID -10
RID LID R-8
LID RID RR73
RID LID 73

where:

• RID is the remote station callsign,
• LID is the local station callsign,
• GRID is the local station grid,

In this case, -10 is the signal report sent by the remote station as it answers the call from the local station and represents the quality of the transmission of the local station as it is received by the remote station. The local station then acknowledged the signal report of the remote station by answering back with its own signal report R-8 where R stands for an acknowledgement (roger) and -8 is the signal report.

   ^                                    ^
   | HELLO RID?                         |
   |         HI LID, YOUR SIGNAL IS -10 |
   | RID, YOUR SIGNAL IS -8             |
   |                   ROGER, GOOD LUCK |
   | GOOD LUCK                          |
   | +-----+                            | +-----+
   | | LID |                            | | RID |
   + +-----+                            + +-----+

Sometimes, the following pattern might be observed:

RID LID GRID
LID RID -10
RID LID R-8
LID RID -10
RID LID R-8
LID RID -10
RID LID R-8
...

which would indicate that the remote station heard the first call by the local station but for some reason is re-transmitting the signal report, as if the local station cannot be heard anymore and is not going forward to acknowledging the reply from the local station RID LID -10.

However, this is one instance where FT-8 can actually be used for some "useful purpose" such as tuning an antenna rather than just making contacts. Here is how this scheme would go:

RID LID GRID
LID RID -10
RID LID R-8
LID RID -8
RID LID R-1
LID RID -5
RID LID R-2
LID RID -2
RID LID R-2
LID RID RR73
RID LID 73

with the following things happening in order:

• the local station calls the remote station and sends the grid,
• the remote station replies with a -10 signal report to which the station replies with the local report of -8,
• the previous sequence is now repeated a bunch of times with the remote station continuing to send signal reports,
• at some point the remote station closes the session with RR73 and the local station confirms with 73

For the duration of the message exchange, both operators can be tuning their antennas in order to minimize the signal level as it is reported. Again, this will not provide anything precise because signal levels are dependent on so many components that this has the scientific value of licking your finger to check for the wind direction but in case one of the operators is rotating a directional Yagi antenna in the ground plane, perhaps even using remote motor, then the signal report will definitely matter a whole lot and the values will be relatively meaningful due to the overwhelming specifics of a Yagi that will "overrule" other parameters, say, the current atmospheric conditions and at least for this session.

Typically FT-8 QSLs are made with WSJT-X and regrettably since 2.1.2 a change has been introduced that does not change or update the signal report when a line is being clicked. The change was justified by saying that a QSO should contain the signal level that the contact was made at, by essentially gearing the meaning and purpose of digital QSOs towards "making contacts". However, this must not necessarily be the case, and even in terms of "voice contacts", it is perfectly acceptable for two operators to tune their antennas and gear while contacting each other, such that the decision to make that change in WSJT-X does not seem well-founded in terms of HAM radios. Trivially, even during a regular voice contact, both operators DO tune their radios to clear up the reception of the other side and asking if the other side hears you better happens all the time.

In other words, when using WSJT-X, the Tx2 and Tx3 messages would have to be edited manually in order to include the updated signal in case the signal from the remote station changes, because just double-clicking the antecedent message of the station will not update the signal level part even if the signal level has changed within the same session.

Fortunately, there is a way to do this by changing the report box manually using the scroll wheel and sending the updated message. So, instead of attempting to change the message sequence boxes in Tx2 or Tx3, it is also possible to just adjust the report box and the message will be updated.

Alternatively, WSJT-X 2.1.2 can be used instead but note that the support for radios was somewhat worse back then such that older bugs might resurface. For example, on Yaesu radios, selecting a frequency via CAT commands requires specifying whether the tuner will be on or off and WSJT-X at 2.1.2 more than likely ignores the tuner such that WSJT-X sends just the frequency and the radio disables the tuner (which, when using a wire antenna or a dipole, is very very bad).