Thanks everyone for the most useful suggestions. I have now determined that the semi break in delay only works when VOX is activated, so if you are using PTT, which I was, and you press the memory button, there is no delay and the PTT output rattles up and down. With VOX activated the hang time is asserted.
Fortunately, VOX is mode sensitive, i.e. CW and SSB are set individually so one can live with this. I don't understand why you need VOX for Semi break in to work, but that's how it is. The TX suppression is a good thing to have, but in my case it is handled in the transverters. The TX power is only 1mW and it goes straight into the mixer. At that power level it hardly matters if the input pin diodes or relays are hot switching. What does matter is the settling of the output TX/RX relays and this is OK because I switch the PA bias with a 100mS delay so they don't see power until they have had time to settle. A rapidly changing PTT out status is a problem for my system because, a lot is going on in the TX/RX changeover. There are bias supplies and drain supplies to switch and a rapid on/off could defeat my relatively simple sequencing logic. This takes about 100mS and if the PTT drops part way through and then rises again just after, it could result in hot switching. There is a useful K3 option to delay TX by up to 60mS to allow for amplifiers to switch. I am using this as well, just in case. In the unlikely event anyone is interested, I use one of WW2R/G4FREs band selection boards to provide a 12V signal for 4m/2m/70cm/23cm/13cm/9cm/6cm/3cm band. It monitors the K3 RS232 line. It also provides band by band PTT but I don't use that facility, I gate a single PTT line via the 12V per band. In the shack I have two of W1GHZs miniverters, one for 2m and one for 70cm which provide the interface to the microwave transverters. These share a VHF Apollo local oscillator which develops 116 MHz or 404 MHz as required. Some simple diode/relay logic selects which IF, LO and microwave transverter is activated depending on the microwave band. It is designed for 23/13/9/6/3cm but currently only 23/13/9cm are on the mast. My microwave transverters are located 20m away, at the base of my lightweight Tenamast to cut down on cable losses. The 12V per band and PTT signals are decoded with relay/diode logic. I have 1:6 relays at the top and bottom so I only need one TX and one RX feeder up the mast. This saves much weight and each feeder is only 10m long. As the pre-amps and band select are all in a box at the top, I can use a lightweight LMR400 for the RX line. The TX line is LDF4-50, LDF5-50 would have lower loss but it is not flexible enough. Apart from raising the mast, this is all completely automated, (potentially controllable via the internet if only I had a decent broadband connection) and it does not interfere with HF/VHF operation. Mike -- View this message in context: http://elecraft.365791.n2.nabble.com/Feature-request-Disable-Break-In-on-K3-tp7578303p7578335.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
