RE: [Repeater-Builder] fan timer circuit
I will grab my notes on it but as I recall it called for a 12 volt supply when the devices leaked SMOKE at that voltage. I think we had to use a regulator and reduce to a much lower voltage. -I will get back to you on this when I look at the notes. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bob M. Sent: Saturday, December 20, 2008 2:31 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] fan timer circuit I would think that the person who designed it, and submitted it for posting on r-b, built and tested it. Did you have a problem with it? Do you think there's an error in the diagram? If so, it should be fixed. Please provide more info. Bob M. == --- On Sat, 12/20/08, Michael Ryan mryan...@tampabay.rr.com mailto:mryan001%40tampabay.rr.com wrote: From: Michael Ryan mryan...@tampabay.rr.com mailto:mryan001%40tampabay.rr.com Subject: [Repeater-Builder] fan timer circuit To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Date: Saturday, December 20, 2008, 1:57 PM I was directed by someone on the reflector here some months back, to a cooling fan timer circuit that is posted on the repeater builders website. I wonder if anyone has tried to build this? - Thanks - Mike __ NOD32 3709 (20081220) Information __ This message was checked by NOD32 antivirus system. http://www.eset.com
Re: [Repeater-Builder] fan timer circuit
The thermal switches sold for attic fans should work great. I bought one rated at 119ºF at a surplus store. My S-COM controllers all had start-of-activity and end-of-activity macro triggers, which would be a more elegant way to do the timer-based function than a separate board with a 555 IC. Personal opinion, but I'd never put up a repeater that relied on a fan to keep temps within spec. I remember being horrified when Icom repeaters went to using a single internal fan with no air filter blowing through both the PA and power supply heatsinks, with the air exiting through a vent hole in the back. I much preferred the older style with the full-width cast-aluminum sink. 73, Paul, AE4KR - Original Message - From: Michael Ryan To: Repeater-Builder@yahoogroups.com Sent: Saturday, December 20, 2008 11:57 AM Subject: [Repeater-Builder] fan timer circuit I was directed by someone on the reflector here some months back, to a cooling fan timer circuit that is posted on the repeater builders website. I wonder if anyone has tried to build this ? - Thanks.. - Mike
Re: [Repeater-Builder] fan timer circuit
At 12/21/2008 14:15, you wrote: Personal opinion, but I'd never put up a repeater that relied on a fan to keep temps within spec. Yes, fans are not as reliable as 100% passive cooling. Unfortunately, the latter method requires a lot more rack real estate which sometimes ( in my case, always) isn't available. Bob NO6B
Re: [Repeater-Builder] fan timer circuit
I would think that the person who designed it, and submitted it for posting on r-b, built and tested it. Did you have a problem with it? Do you think there's an error in the diagram? If so, it should be fixed. Please provide more info. Bob M. == --- On Sat, 12/20/08, Michael Ryan mryan...@tampabay.rr.com wrote: From: Michael Ryan mryan...@tampabay.rr.com Subject: [Repeater-Builder] fan timer circuit To: Repeater-Builder@yahoogroups.com Date: Saturday, December 20, 2008, 1:57 PM I was directed by someone on the reflector here some months back, to a cooling fan timer circuit that is posted on the repeater builders website. I wonder if anyone has tried to build this? - Thanks - Mike
