Sequencing of various voltages and r.f. switching is necessary for the W1GHZ simple transverters. This web page will show some possibilities. Sequencing can be very simple as shown below with the writeup by Gary Rheuark, K5QNM, or they can be more complicated/protective/fool-proof/expensive as detailed in the references.
http://4smicrowave.ae5k.us/gbuy/k5qnm_sequencer.pdf
http://www.w1ghz.org/small_proj/sequencer_V2.pdf
http://reality.sgiweb.org/overby/ham/Equipment/Sequencer/seq1.html
http://www.w6pql.com/relay_sequencer.htm
http://www.downeastmicrowave.com/PDF/trs.PDF
http://www.jwmeng.com/seq1.html