Transmit Delay

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I have a 6500 and a non-QSK amplifier.  I want to setup a delay for T/R switching.

What is the difference between these in Radio Setup -

And this in SSDR -

And which do I use to set a 30ms delay for the relays in the amp?

73 de K1ESE
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Posted 3 years ago

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Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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Official Response
So this is my take on it and anyone correct me if I am wrong.

The bottom delay is for CW so ignore that one for the time being,

The RCA TX1-3 and ACC TX are the RCAs in the back of the radio to engage devices such as amps, transverters, etc... when you PTT de radio.

This is where you could define a SEQUENCE in the engagement of devices. For example, you might want to engage a relay that shuts off a preamp on a receiving antenna a few ms before it engages the amp. So you might have the PreAmp on AccTX with value 0 and the amp connected on TX1 with a value of 20 (which means 20ms).

The TX Delay then can have the amount of time between the moment you press PTT on the radio and the moment the Power Amplifier of the Flex sends RF into your amp. You could set this to 30ms.

In that scenario, once you push PTT in your Flex the PreAmp shuts off right away, the Amp receives the PTT signal 20ms later and 10ms after that the Flex radio send RF.

TL;DR TX Delay is the one that will define the amount of time between PTT depress and RF being sent out of antenna port.

You can test this yourself using 1000ms for the TX Delay. That equates to 1 second and you can see that your amp gets the PTT signal right away but there isn't any power until 1 second has passed. When you use 6 ms or even 20ms is not perceptible to the naked eye.