It looks very professionally done. I use something similar, except that it is glued to a heat sink fin.
Richard www.n7tgb.net The problem with socialism is that eventually you run out of other people's money --Margaret Thatcher _____ From: [email protected] [mailto:[email protected]] On Behalf Of Eric Lemmon Sent: Saturday, May 01, 2010 5:29 PM To: [email protected] Subject: RE: [Repeater-Builder] Neat kit for switching repeater devices Larry, My first use of this thermal switch was on a solar-powered Motorola R1225 UHF repeater at a commercial site. I simply drilled and tapped two 4-40 holes on a flat portion of the outside fin, and mounted the thermal switch after applying some heat-conductive paste. I used a three-inch low-EMI Panasonic fan blowing right on the fins. This is a 45-watt repeater set for about 30 watts output. It went into service early in 2003, and has been trouble-free ever since. I have attached a picture of what it looks like. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com [mailto:Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com] On Behalf Of Larry Horlick Sent: Saturday, May 01, 2010 11:56 AM To: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices Eric, This is good info. I have an immediate use for this. How have you actually attached this 'stat to the fin? Larry On Sat, May 1, 2010 at 2:36 PM, Eric Lemmon <wb6...@verizon. <mailto:wb6fly%40verizon.net> net <mailto:wb6...@verizon. <mailto:wb6fly%40verizon.net> net> > wrote: Scott, I must agree that the CK1614 is an extremely versatile timer, with many potential uses. However, using it for fan control is not only expensive, but unnecessary. A fan blowing on a transmitter heat sink does absolutely nothing immediately after the transmitter is keyed, since the heat sink is likely at ambient temperature. It takes a period of time for the heat sink to warm up, so operating the fan prematurely is a waste of energy- which may be an issue for a solar-powered repeater. IMHO, the most efficient means of fan control is also the cheapest: A thermal switch. My first choice is a Cantherm #R2005015 normally-open thermostat that closes at 50 degrees Celsius, about 122 degrees Fahrenheit. When attached to a heat-sink fin, it turns the fan on when necessary, and keeps it on until the heat sink cools below about 100 degrees F- around body temperature. This particular switch is available from Digi-Key for about $9, as Catalog Number 317-1094-ND. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> [mailto:Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> ] On Behalf Of na4it Sent: Saturday, May 01, 2010 9:38 AM To: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> Subject: [Repeater-Builder] Neat kit for switching repeater devices I have started using this little kit (http://www.electron <http://www.electronickits.com/kit/complete/elec/ck1614.htm> ickits.com/kit/complete/elec/ck1614.htm <http://www.electron <http://www.electronickits.com/kit/complete/elec/ck1614.htm> ickits.com/kit/complete/elec/ck1614.htm> <http://www.electron <http://www.electronickits.com/kit/complete/elec/ck1614.htm> ickits.com/kit/complete/elec/ck1614.htm <http://www.electron <http://www.electronickits.com/kit/complete/elec/ck1614.htm> ickits.com/kit/complete/elec/ck1614.htm> > ) for fan control on repeaters. I can also be used as a PTT and Time Out circuit, along with a lot of other uses. Download the pdf on that site and check it out. Scott NA4IT
