I had the very set-up you are considering building - also using the 4 position Alpha Delta switch. I am now converting back to a modified manual set-up.
Why? the Alpha Delta switch developed a fault -- if you open it up you will find that the mechanism is a thin strip of metal which is pressed to make contact with each respective contact of the 4 positions as you move the knob into the next detent. It seems the metal strip was mounted by the manufacturer "not centered", so that after only after a short period of usage (2 months after installing a new unit) the contact made to the 2 positions on one side of the switch were poor or even intermittent. It cost me shipping my K-3 back to Aptos both ways and repair costs - and Elecraft was very nice to me on repair costs, even though this was clearly my fault. So, as a matter of QTH operating philosophy, I have now purchased a MFJ coax patch panel, have labeled all inlets and outlets of the panel and each piece of coax in my QTH on both ends -- and have designed and made copies of a check list which I use each time I re-configure. Perhaps overboard -- but it was an expensive lesson learned. FWIW. Regards, Erwin KI4TBD Canton, GA, USA "Join the DARC side! Deutscher Amateur Radio Club!" Greg Buhyoff wrote: > Group, > > This is off topic and I would deeply appreciate any responses to be > sent to me off list. I am posting here because I respect the > knowledge and experience of the people who are members of this > reflector. > > This may sound stupid but I have not had experience with this before, > so I ask before I do something stupid. > > I use an external antenna switch mounted on the outside wall of my > house to switch in one of six antennas and have a single coax line > coming into the radio room. I now have four separate radio stations, > 2 K3s and two other radios, all set up differently for different types > and modes of operation. All have amps in line that can be used when > needed -- one a KW and the others 750w output. Currently I manually > attach the output coax for the station I want to use to the coax lead > coming into the house from the external switch. A pain. > > I want to be able to simply use a manual switch to select the station > that would connect to the external antenna switch coax lead into the > radio room. I would then use the manual antenna switch to select the > station and the remote controller to select the antenna. I was > looking at the Alpha Delta manual switch with four switched ports and > a common and then would connect the common to the coax lead coming > from the external antenna switch (DX Engineering) and then each output > coax from each of four stations to the four ports on the Alpha Delta > and then could switch stations via the Alpha Delta manual switch (all > ports not selected go to ground) and, obviously, then select my > antennas as I have been doing using my remote antenna switch. > > Again, this sounds stupid, but I have not had to do this before and > always used manual "antenna" switches to simply select antennas. My > question is this: > > Given the Alpha Delta manual switch has >60dB port isolation -- is > this isolation good enough that I can use the this manual switch to > select stations even though each of the stations has the capability > delivering up to 1 KW output? I don't want to blow out the front ends > of the radios connected to this manual switch. > > I appreciate any answers that can be sent on to me. I know this > sounds stupid, but I have been a ham since 1958 and simply have not > had or needed to do this. I now have four great stations that I > carefully put together as part of a "plan" when I retired and I don't > want to do something stupid at this point. I have done plenty of > stupid things in the past and more will happen, but I thought I could > simply ask a question here with hopes someone can allay my fears of > using such a switching setup or educate me in those things I don't > understand or did not think of. > > Thanks so very much and 73, > Greg K2UM > > ______________________________________________________________ ______________________________________________________________ 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
