Transceiver

The combination LT70S + IC-746 is not really satisfying because of the 10m - IP3. (see 144MHz) so we kept the "good old" IC-475 as backup running.
 

The PAs are also homebrewed by DK4RC.Construction details see 144MHz.
 

Also the same situation as on 144MHz. Depending on the "man power" the main antenna is a 4 x 13el Flexa group and the 2nd antenna is 2..4 x M² 432-13WL.
 

The antenna switch handles two separate antenna systems . There are some different operation modes depending on how may PAs and Tcvrs are used. Two separate foot - pedals handle both PTT and antenna switch. This keeps the OPs hands clear and provides a kind of "rallye feeling" :

Configuration with 1 PA

Configuration with 2 PAs

A nice feature is the use of a second transceiver as an additional Rx. The two antennas are cross connected to both Rx and the AF is fed into stereo headphones. The OP has the choice : RX 1 only, RX 2 only, "stereo". In all cases the antenna assignment can be reversed by the foot - pedal.
The 3dB - Splitter is a commercial antenna coupler mounted external and can be changed for 144 / 432 MHz.

Inside the box : principal schematic of the switch with 1 Tcvr

Same with 2 Tcvr, the 2nd is used as Rx only, antennas are cross connected

The handling of such switches is not so easy, some sequencing and interlocking must be done to protect the PAs, antenna relays and the OP :

Schematic of the control PCB, pins are numbered as shown in the pictures above