There are solid-state relays in a DIP-6 or a SOP-4 package that can fit most places and are fast. Check out the NEC PS7113 or PS7141, and similar devices.
73, doug X_CMAE_Category: 0,0 Undefined,Undefined Date: Thu, 12 Feb 2009 11:00:27 -0500 From: Don Wilhelm <[email protected]> Terry, For those who prefer not to touch the K3 with a soldering iron, an external 12 volt relay is a good solution. Obtain the power from the K3 12VDC OUT jack and use KEYOUT to key the relay. It accomplishes the same thing and retains the ability to use QSK in the future without 'undoing' the internal relay. 73, Don W3FPR [email protected] wrote: > > I've seen numerous posts about the PTT output line on the K3 and using > older amps. Yaesu's, Kenwood's, Icom's all share the same issue. > > > > Unless you are running QSK and need instant keying, I would suggest > adding a small 12v relay inside the K3 that the solid state device > keys and presents the user with a set of dry, isolated contacts that > can handle positive, negative and up to 250v DC or AC. I have added > this to several K3's to protect the switching transistor from eventual > destruction. Once again, if you are using QSK, solid state due to it's > fast switching time is your only option. > > > > Yes, it means touching your K3 with a hot soldering iron, but it's a > "pay me now or pay me later" thing, sooner or later it will blow the > switch if you are hooking up older or HB amps that use other than low > current positive keying voltages. > > > > Terry > > ______________________________________________________________ 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 ______________________________________________________________ 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

