When I built my KPA100 back in 2003 my kit was short part of the fuse holder so I went down to the automotive store and bought one. A few months later my K2/100 started shutting off unexpectedly while transmitting. I discovered that the fuse holder was warm enough that the plastic was softening slightly, allowing it to stretch so the spring loaded contacts no longer pressed hard enough against the fuse! The lighter the contact, the more the resistance, the more the resistance the more the holder stretched under the spring pressure.
I had long since received the axial fuse holder Elecraft uses and installed it. I've not had an issue since. I assumed the holders Elecraft sourced used a more robust plastic. However, if that ever happens again, I'll switch to the blade-type automotive fuses. As you noted, their contacts are larger and should have much lower resistance. Also, the electrical contact pressure doesn't depend upon the molded plastic like axial type holders do. I think there's a reason we don't see axial type fuses in automobiles any longer and I sure don't experience fuse holder failures in my car! 73, Ron AC7AC -----Original Message----- It looks like one of the causes of my chirp on 222 MHz with the K2/XV222 combo was an unreliable fuseholder (an in-line type for an AGC/3AG/1-1/4x1/4 inch fuse). I wonder if automotive blade type fuses/holders might be more reliable as far as contact resistance goes. Does anyone have any good knowledge on this ? 73, Steve VE3SMA ______________________________________________________________ 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
