[PapaErde]

Thanks for the help werk_ag.  I´ve recognised the 82B715 as TX chips on the main TX board. But i was searching for the part list of the extender pcbs and found it here https://www.meteocercal.info/forum/thread-1898.html 

Maybe the TS922 was mistakenly added by heavyweather on his digikey-list. So again: Thanks for the service and maybe he´ll check the shopping list.

Greetings from Austria