Can the Pluto cause tx RF spikes?

  • I have bought a Bison three semiconductor PA and the seller warns that my Pluto, (and then an Analog Devices preamp) can cause high level TX spikes as it occasionally self calibrates. These can apparently kill the PA. I have not heard of this before, and have not had an issue with my current LAN connected Pluto - AD preamp - SG Labs 20W power amp into a POTY.


    How should I go about stopping this risk?


    I want to have as much gear as possible in the cabinet, which has mains power available, under the dish, including the new PA and AD preamp,


    At the moment a LAN cable and the LNB coax for the wide band polarisation connection to the 4 port LNB are all that need to come back to the shack. This set up allows me to run SSB using SDR Console on the narrow band transponder via the LAN to the Pluto, and one LNB port, and low power to the wide band transponder for DATV, with a Minitiouner for RX off the LNB cable into the shack, from another LNB port. I am currently using a Portsdown for TX. The Portsdown is LAN connected to the Pluto at the dish.


    Adding this much more powerful PA is looking more complicated than I thought as the SG Labs PA uses VOX instead of electrical PTT. Are others troubled by this calibration spike when running higher power PA's and need to get the Pluto TX'ing before turning on the PA, presumably manually or with some sort of PTT timer arrangement?


    I have built the PTT relay board to go inside the Pluto, but had no need to fit it yet as the SG Labs 20W PA uses VOX to go to TX mode. I am getting a bit confused as to what's needed to protect the new PA now, with the bigger Bison PA which has been built to have a lot of gain meaning the Analog Devices preamp should very easily drive it.


    Any advice most welcome, thank you.


    *EDIT*


    I have read a BATC article describing an out of band high level TX when the Lime Mini SDR is self calibrating, I wonder if the vendor is getting confused and thinks the Pluto SDR also do does this, or is the one that has this issue?