enforce static Tx Pct rate in WSJT-X to get simultaneous spots with friends for comparison

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DD5XX's picture
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enforce static Tx Pct rate in WSJT-X to get simultaneous spots with friends for comparison

Hello all,

certainly you all know the setting "Tx Pct" that you set in WSJT-X software when using WSPR mode. If defines the transmit percentage when you transmit and receive.

Some ham radio friends of mine want to perform some TX tests during 24 hours operation with 4 different stations and our goal is to transmit on exactly the same 2-min time slots and thus get simultaneous spots. Unfortunately this does not work because each of our stations running WSJT-X is generating a randomly TX time slot although we all setup the same TX percentage value and start our transmission on the same time slot.

For example: all of the 4 stations are using the same WSJT-X version and we did setup "Tx Pct = 20%". All together we start sending on 14:00 UTC. Now it happens that on 14:12 UTC only station4 did TX, on 14:14 UTC station1+station3 did transmit and on 14:16 station2 transmitted. This is just an example out of my head and does not reflect the real experience.

The WSJT-X 1.9.1 manual says:

If you will be transmitting as well as receiving, select a suitable value for Tx Pct (average percentage of 2-minute sequences devoted to transmitting) and activate the Enable Tx button. Transmitting periods are also 2 minutes duration, and will occur randomly in time to reduce the chance of clashing with other stations you may be monitoring.

I understand the meaning of this random function and it's generally ok but we really like to have a static value when transmitting so we can achieve simultaneous spots even when TX during the whole night. Actually we can do so only if we would use Tx Pct = 100% which is certainly not we want. One more reason we are looking for a way to configure a static and not randomly generated TX time slot is when it comes to RX. We live nearby and if 2 of 4 stations of us are transmitting on a time slot where the other 2 stations are receiving this cause strong signals on one of the two RX stations. The strong signal affect a long-time analyze of the reported SND even when using AGC.

For the given reason we are looking for a comfortable way to "teach WSJT-X" to use a static time slot for the TX Pct rate we are configuring in the software. Is anyone aware of such a configuration option, any clues? We are really looking forward to any comments and help.

Thanks to everyone in advance.

vy 73 de DD5XX