As I hit the send button a solution came to mind, if you built a circuit like the gauge circuit, with a larger resistor for the clock voltage, you could include a fan from a computer to cool the processors in the build over the heat sink to keep things cool. Herb -------Original Message------- From: Herb Date: 1/31/2009 12:17:21 PM To: 1962to1965mopars@xxxxxxxxxx Subject: Re: Alternative on Dash Clock Conversions The clock is not creating the heat the resistor reducing 12v to 1.5v is the culprit. For example building the circuit to run the gauges needs a heat sink for the resistor going from12v to 5v and it runs Hot. The bottom line, resistance = heat. I would almost guess the extra heat generated dropping to1.5v would cause damage to the dash if the heat sink was mounted on it. With that big of drop you might look at mounting the heat sink to the fire wall or something not affected by heat under the dash. Just my II. Herb St. Louis, MO. -------Original Message------- From: Dodger7998@xxxxxxx Date: 01/31/09 10:51:13 To: 1962to1965mopars@xxxxxxxxxx Subject: Re: Alternative on Dash Clock Conversions really stretching my memory here, but would think that the value of the resistor would be 7 times the resistance of the clock, and that there combined resistance would make the 8, and as far as the heat,,,,,I can not believe that the power used by a clock would cause any amount of heat, surely there is some one on the list that has been to school since I have that could clarify this In a message dated 1/31/2009 10:15:39 A.M. Central Standard Time, pjlenn@xxxxxxxxx writes: That's what I was trying to get to with the father-in-law. How do you calculate the value of the resistor needed? But I couldn't quite get him to give me a straight answer. So I looked around a little in some of my old stuff and found a slide type Ohm's Law calculator. It will Give me the value of the resistor if I know the voltage (12) and how many milliamperes the clock will draw. So, would you then multiply the value it gives you for the resistor x's 8 as discussed in the previous post? I don't know. Probably just easier to grab a handful of resistors and a voltmeter and experiment a little. If you used a higher wattage resistor it might take care of the heat issue. A heat sink would probably make everything last longer. Paul L. '63 Sport Fury 440/727 http://www.1962to1965mopar.ornocar.org/ml-lennemann63.html [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. This email was sent to: arc.6265@xxxxxxxxxxxxxx u/?bUrDWg.bSONJP.YXJjLjYy ?p=TEXFOOTER