Beacon Transmit and Receive Timing -

There is now a capability to have the transmit/receive toggle on a timed basis. This has been nicknamed the "Beacon Mode," but is not really a mode, it overlays any mode. So you can use it on USB or FM if there is an application. Do Not use it with EME2; this makes no sense. The operation is simple: If activated ( ALT-H or ALT-h) toggle between Transmit and Receive with the specified time pattern.

This can be especially useful for PUA43 mode where weak signal operations might take hours. Originally T/R was done by manual operator intervention. With the advent of the LTI mode automatic T/R has seen many months of use in propagation studies on 10 GHz, and recently on 24 GHz.

Beacon Overlay changes

Beacon operation has been rewritten to reflect the new clock system, but continues all the old features, except b_minutes 60, 30/60 minute option. See the configuration file variables, listed below ,or the configuration file for more information.  

The following variables can be set from the SCRL-F2 dialog box.


b_transmit_sec The number of seconds that transmission occurs
b_receive_sec  The number of seconds that receive occurs, after transmit
b_offset_sec    The number of seconds of offset for both transmit and receive
lt_b_save         If 1 there will be data saved in LTI from the yellow trace
lt_b_clear        If 1, the LTI yellow trace will be cleared after the data save
b_active1        The starting minute of each hour for which beacon is active
b_active2        The first minute of each hour for which beacon is inactive.

These can be set in the UHFA.CFG or in the Beacon dialog box by  SCRL-F2 .  Data is entered by "backspacing" over the data and typing in the new data. Use "TAB" to move to the next line, and "ENTER" to quit and save the new settings.

The variable b_active1 has always been around, but not in the SCRL-F2 dialog box. 

Some discussion of the timer used for this function:

The timer runs  24 hours before resetting with timing referenced to UTC midnight.   7200 seconds is the largest even number that can be entered in the SCRL F2 dialog box, though it is possible to use 9999.

When "beacon mode" is active T/R will toggle according to b_transmit_sec and b_receive_sec,  The convention is to list the transmit interval first, then the receive interval and finally the start time. This order is consistent in the F2 Dialog Box and the screen display when "beacon mode" is active.

The listing shows how long to wait before transmitting, how long to transmit and how long to receive. Once started, the sequence is continuous.

To operate as a beacon, transmitting the last minute of the hour,

   b_transmit_sec   60 
   b_receive_sec   3540 
   b_offset_sec      3540

This says,
wait for the 3540th second (3540/60 = 59),transmit for 60 seconds then go to receive for 3540 seconds.
transmit for 60 seconds then go to receive for 3540 seconds
transmit for 60 seconds then go to receive for 3540 seconds

To operate as a beacon, transmitting one minute each hour,during the first minute

   b_transmit_sec  60
   b_receive_sec   3540
   b_offset_sec       0

This says,
wait for the  0 second ,transmit for 60 seconds then go to receive for 3540 seconds..
transmit for 60 seconds then go to receive for 3540 seconds
transmit for 60 seconds then go to receive for 3540 seconds
A very common interval used for LTI is five minutes on and five minutes off.

Station A
b_transmit_sec  300  
b_receive_sec   300 
b_offset_sec     300

Station B
b_transmit_sec  300
b_receive_sec   300
b_offset_sec       0

If I wanted to have a sked with me transmitting 2nd and 4th 15 second periods I would use
   b_transmit_sec  15 
   b_receive_sec   15 
   b_offset_sec      15

The other station would use

   b_transmit_sec  15 
   b_receive_sec   15 
   b_offset_sec      0


Another instance:
 If Mike, Ernie and Larry wanted to send for "rotating" 5 minute periods, they could each set up

   b_transmit_sec 300 
   b_receive_sec  600 
   b_offset_sec     0 
   b_transmit_sec 300 
   b_receive_sec  600 
   b_offset_sec   300 
   b_transmit_sec 300 
   b_receive_sec  600 
   b_offset_sec   600


If I wanted to use the timing to write data to disk every two hours,

   b_transmit_sec  0 
   b_receive_sec  7200 
   b_offset_sec    0

and check the "Save LT data to Disk" box in the
F2 Dialog box. The "Clear --" box should be
checked also for data saves.

The annotation in the lower right corner of the upper spectral display is the same order as above. It is a reminder that the beacon operation is running.

All characters, except the tilde, '~', are completed before transmit is stopped. This may overrun the receive period, if the sending is slow. The '{' and '}' are still available in CW and LTI to send or not send one second time periods. This may be useful to hold the key down without messing up the timing.

The HOME key operates, during Beacon operation. The HOME key will interrupt transmit.and return to receive. In order to not return to transmit, the beacon operation will automatically be turned off.  Likewise, if the beacon operation is turned off (Alt-H) when in transmit, the radio will go into receive and the beacon operation will be turned off.

Other regular keys are available in T or R as are allowed.

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