Follow the instructions and check the + terminal to - with an ohm meter for any shorts. The problem you face is the transistor is the worlds fastest fuse and on initial turn on you are looking at a low current surge as the unit charges the supply and decoupling caps. A full current rated fuse will not protect the PCB if you did something wrong, nor will current limit if set for the max current the K3 will draw on transmit.
If you test the resistance first, the chances are you will be safe on initial power up. Like one suggested using a current limiting PS set say at 3 amps, that will protect you adequately. When the K3 comes alive, you can increase the current limit to operating conditions. I hope this helps. Mel --- On Thu, 8/12/10, ab2tc <ab...@arrl.net> wrote: From: ab2tc <ab...@arrl.net> Subject: Re: [Elecraft] K3 inline fuse To: elecraft@mailman.qth.net Date: Thursday, August 12, 2010, 3:13 PM I completely agree with you. The inline fuses are there for mobile installations where you have a direct connection to the car battery. On my ICOM radios I have always shortened the power cable removing the inline fuse in the process. AB2TC - Knut David Cutter wrote: > > You are much better off using the current limiting feature of your dc > supply. A fuse is not fast enough to protect any electronic circuitry. > Strictly speaking a fuse in line is rated to protect the cable in the > event > of a short circuit in the rig which would be a very big fuse, far bigger > than your psu is rated to supply most likely. Fuses and their holders are > too slow and drop valuable volts along with the cable drop and connectors, > which all add up to a poorer distortion figure on transmit. > > David > G3UNA > <snip> > -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-inline-fuse-tp5414371p5418061.html Sent from the [K3] 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:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
