Jon, Look to computer shops for fans from defunct computers - often you can get them for free.
Put a resistor in series to reduce the fan speed (and noise), and place the fan over the PA transistor area of the heat sink. The fan should pull air away from the heat sink for the most effective cooling. 73, Don W3FPR On 10/2/2010 8:54 PM, Jon Perelstein wrote: > Don, > > Thanks for the response and info. > > The wording in the Operating Manual made me think that the same values are > used > for RTTY as for SSB, my mistake. I used Spectogram (surprisingly easy) and > have > everything working nicely now. > > On the digital transmission heat issue. The rig is ok on 1-2 minute digital > transmissions (e.g., 1-2 minutes of PSK at 30 watts). It'll warm up a bit, > although nothing uncomfortable, and the internal fan can handle it. The > problem > is longer transmissions. For example, I do a lot of file sending for EmComm > simulations and those transmissions can run 5-10 minutes at a time. The area > above the power transistors gets very uncomfortable on a long transmission > like > that and people notice drift in my transmissions. > > For now I've got a desk fan pointed at the rig when doing longer transmissions > and that's keeping the rig cool and stable. I'll find myself a muffin fan or > smaller desk fan at the next hamfest. > > Jon > KB1QBZ > > > > ________________________________ > ______________________________________________________________ > 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
