SW1, 2 and 3 above decides which 2 of the 3 radios are to be used during the contest. It even allows you to choose which one to use as radio 1 or 2. To enable this 3 standard 3-way switches are built into a small box and used for each radio. The positions switchable are Radio1, Radio 2 or Standby. This is usually set up and tested a couple of days prior to a contest.
Radio 1 connects the RF output of the tranceiver direct to Hoscha 1, a motor driven coaxial switch. It also connects the PA relay circuit to PA1.
This way Radio 1 will be connected to RatPak Radio 1 through Band Pass Filter -1 and PA 1. Alla antenna switching is done by RatPak Radio 1.
Radio 2 connects the RF output of the tranceiver through a coaxial relay to Hoscha 2. It also connects the PA relay circuit to PA2.
This way Radio 2 will be connected to RatPak Radio 2 through Band Pass Filter -2 and PA 2. All antenna switching is done by RatPak Radio 2.
The Standby position leaves this tranceiver unconnected.
The Band Decoders are delivered by Top Ten, www.qth.com/topten/, and serves the purpose of automatic switching of the BPF´s, delivered by Array Solutions - www.arraysolutions.com, as the bands are changed. The switching of which rig to use is done manually prior to the contest. The EZMaster an all mode - all in one PC interface, www.hamradiosolutions.com, which takes care of the keying and switching of the radios is described below. PA1 is switched directly by Radio 1. I might re-build the switching of the BPF´s and use the output from the EZMaster instead of the Band Decoders at a later stage.
Two VFD SWR meters are connected after the PA´s and they monitor the SWR as well as show the output power. The relay control from the X-mitter is routed through the SWR watch of the VFD. If a SWR above 2:1 occurs the keying of the PA is disrupted immediately. The SWR watch can be set for various values and the PU-unit is located near the PA and the actual meter close to the rig.. The VFD´s are obtained from Array Solutions.
This way the PA´s are protected should the wrong antenna be connected or a malfunction of an antenna occur.
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