The answer is in the quoted message below, but I'll repeat it since it perhaps wasn't clear enough. The suggested thermal switch is available from Digi-Key as their catalog number 317-1094-ND. The Digi-Key home page is www.digikey.com If you type "317-1094-ND" into the search box, it will open the page at which the switch can be ordered.
Yes, you can wire two or more thermal switches in parallel, so that the fan runs whenever any monitored device exceeds the temperature setting. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of wqjf348 Sent: Thursday, October 16, 2008 5:18 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: GR500 Cooling Fan Control Thanks for the reply. Do you have a good source for that part? Also, could I wire two of them in parallel, one on the radio heat sink and one on the power supply sink? Thanks, Ben --- In Repeater-Builder@yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> , "Eric Lemmon" <[EMAIL PROTECTED]> wrote: > > Ben, > > I believe that the best solution is to use a normally-open thermoswitch > mounted to one of the heatsink fins. My choice is Digi-Key 317- 1094-ND, > about $7, which closes at 50 degrees Celsius (122 degrees Fahrenheit). This > setting ensures that the fan does not run needlessly, but will kick in long > before the radio gets hot enough to affect its health. I drilled and tapped > a couple of 4-40 holes, and mounted the switch with some heat-sink compound > under it to get good heat transfer. > > 73, Eric Lemmon WB6FLY > > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> > [mailto:Repeater-Builder@yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> ] On Behalf Of wqjf348 > Sent: Saturday, October 11, 2008 11:39 PM > To: Repeater-Builder@yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> > Subject: [Repeater-Builder] GR500 Cooling Fan Control > > I am setting up a GR500 with the R1225 radio. It is in the wall mount > box. The cooling fan that came with the box runs non-stop. > > I would like to be able to control the fan either by slowing it down > or making it switched by temperature or PTT of the repeater. > > Can anyone here offer some suggestions? It is currently wired > straight from the power supply. > > Thanks in advance! > > Ben > WQJF348 > West Jordan, Utah >
