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## Re: [Amps] Advice needed for SS amp

 To: Manfred Mornhinweg , "amps@contesting.com" Re: [Amps] Advice needed for SS amp "Fuqua, Bill L" Fri, 7 Jun 2013 03:46:20 +0000 mailto:amps@contesting.com>
 ```We had a professor with a large water cooled 3cv10,000 tube in a DC electron metal evaporator power supply. Guy working on a shoe string budget. It was donated. He could not run tap water thru it so I had him get a 55 gallon drum and fill it with distilled water. Pump and a deionization filter was attached. He did ultimately cool with tap water by running the tap water thru 1/2 inch cooper tubing in a coil placed in the drum. Worked great! He did not need all the full capacity of the power supply and he was able to cool it and his e-gun evaporation system at the same time. As I said, he was on a shoe string budget. This power supply put out over 5kV at few amps. 73 Bill wa4lav ________________________________________ From: Amps [amps-bounces@contesting.com] on behalf of Manfred Mornhinweg [manfred@ludens.cl] Sent: Thursday, June 06, 2013 10:08 PM To: amps@contesting.com Subject: Re: [Amps] Advice needed for SS amp Larry, Jim, > Any one want to check my math? I checked it, and Larry is right. A half gallon of water (1893 milliliters), which has a specific heat of roughly 4.19 joule per milliliter per kelvin (the actual value varies slightly with temperature), heated for 5 minutes (300 seconds) with 1500 watts, would warm up by 1500 * 300 / 1893 / 4.19 = 56.7 kelvin, which is the same as 56.7 degrees Celsius. Hardly enough to make it boil, unless it was pretty warm to begin with! Starting from typical tap temperature, and considering some loss that ends up heating the kettle and producing some steam, the actual time required for boiling would be somewhat between 7 and 8 minutes, assuming the power is actually 1500 W and the water volume is actually half a gallon - and that the water is pure, not mixed with some liquid that has a lower specific heat! Now I don't think that anyone will boil a water/glycol mix to make coffee, but it's very possible that the heater actually is consuming more than 1500 W, or that the amount of water is somewhat less than half a gallon. This illustrates that cooling a legal limit amp with a bucket of water under the operating desk is a satisfactory method for casual operation in SSB, but won't cut it for a full weekend of RTTY contesting! Manfred ======================== Visit my hobby homepage! http://ludens.cl ======================== _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps ```