Multiple Simultaneous Transmissions Possible?

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I am new to SDR and I was wondering if it would be possible transmit a digital signal and a voice signal on two different frequencies through the same antenna at the same time. e.g. Have a winlink session going on say 143.5 and then have a voice conversation on 144 while the winlink was still going on. This assumes that there is a receive antenna and a transmit antenna.
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A Skispcs

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Posted 1 year ago

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Walt

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Commercial radio services combine transmitters on to a single antenna all the time.  It takes a certain amount of engineering and a large amount of money to purchase the filters and isolators that make it work.  The frequency numbers you give do not seem to match any frequency that a Flex radio would transmit on, so this answer is limited.

Cheers !
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A Skispcs

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Sorry my explanation was poor. I am not trying to tie two separate transceivers onto one antenna, I am interested in if a single SDR transceiver can handle multiple transmissions such as a winlink connection and voice at the same time.
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Walt

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I do not know of a commercially available SDR transmitter that can do that.  The government has special-use transmitters that do (things like look-down-shoot-down radars), and I believe the cellular industry also has multi-mode/frequency systems designed into a single transmitter, but none available for amateur radio use.

If you want to take the time and energy to roll your own, here is a starter article that discusses what it takes to program subsystem modules to complete a system of your own design.

https://www.digikey.com/en/articles/techzone/2014/feb/building-a-software-defined-radio

Good luck with what you are working on.
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Martin Ewing AA6E

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The Flex 6000 series (for example) has only one TX channel that is up to 10 kHz wide (from memory).  So you can transmit as many data-type signals as you want, if you cram them into that same bandpass.

I have toyed with the idea of carrying on multiple simultaneous JT65/JT9 QSOs.  That's possible if they all transmit at the same even/odd minute in the same band!  
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Bill W2PKY

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I have seen one station run two instances of WSJT-X and combine the audio to effectively transmit 73 to one station and CQ at the same time. Only one slice flag can have the "TX" ICON active at a time.
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Martin Ewing AA6E

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The logistics -- remembering where you are in multiple QSOs -- gets complicated.  Does this count as multi-transmitter in contests?  Etc.