One of the main issues I wanted to solve for enclosing the radio was cooling, for this I had decided on 80mm PC case fans, which are widely available and in my case as I have pulled many a PC apart over the years free of charge subject to testing.
So, a short while ago I dug out two such fans, one was removed from the remains of a computer power supply that went pop some years ago, the other from a chassis which I don't think I'll ever reuse, the latter seems to spin a bit faster than the former but this is not a major problem.
One thing I alluded to was that I would set the fans up so colder air would be brought in and hot air removed, these fans don't work if wired up backwards however on them are arrows indicating the direction of rotation and the airflow so can be fitted either way, I also found two grilles, one silver coloured off the power supply I alluded to and one gold coloured off an old computer case which I use as a groundplane for indoor 10-metre use on a CB antenna (the grille was removed before the case was put to that use).
The fan on the radio itself will always start when the radio is keyed up, I noticed this a lot when operating APRS, however I want these vent fans to start if the temperature is above a certain point though not too high, enough to keep the radio cool and a decent airflow around it, I plan to keep the radio as close to the two fans as possible, these will be mounted into the top of the enclosure, the main use for the enclosure is to protect the radio and allow for extra sockets for 12-volt accessories such as the mini fridge or a compressor.
Construction on the enclosure begins this weekend and the relay is also due to be fitted to the car then as the loom required is on its way (I can repin it if the pinout does not match my car (that is not straight through) which I will test with a multimeter), this will give me a good opportunity to test the relay to ensure it works and also find a suitable place to mount it, the relay is rated to 40A and I don't think that a couple of fans and a temperature control unit will add much more on top of the 35A I have calculated maximum for the current draw (though I chose 50A cable to do the job so the only real failure point is the relay.
Given my house move I am amazed I could still find these old fans lying about, and the grilles for that matter, to be honest I don't mind which colour each one is, just that they be there to protect people from putting their fingers onto an operating fan.
73 de 2E0EIJ
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