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Well lets see here DOC and Frank
Have you tried a Large farad cap on your amp? I thought not. So unless you have then don't cut it. Frank you need to learn what ESR is you ****en dum ass. These cap have a very LOW ESR as I said in my first post I or do you not read very well. Doc , it works, and you know it could unless your a Dumass also. so why put your little ****ty wisdom comments in Sure its costs money, but to me running several alternators and a big amp just to say Audio is a waste of money to me. We all have our quirks. Why do CBERs spend good money just to raise the power out on a 4 watt rig to 7 watts and think its walking the dog, cant tell it on the receiving end. O well beleave what you want. He asked a question and I gave a good answer, it works. Then here comes all the so called Brains on this group. Hell I dough if they really do anything with there's, just sent on their ass and tell every one else how smart they think they really are . SO called DOC is really a flunky, and Frank hell he must work for some portal potty outfit. Dam It would be nice if they could just give a answer without trying to act as if they are the only ones in the world with knowledge. **** them two. Frank go and get one of those caps there are very LOW "Frank Gilliland" wrote in message news ![]() In , wrote: On Mon, 8 Dec 2003 03:23:00 -0600, "Dr. Death" wrote: I noticed that a lot of high end auto audio systems use a capacitor in series with the main power lead to the amplifies so the amp hits harder. Could this same principle be applied to ssb, I think it can. place a 1 farad audio cap inline with the power lead to say a Texas star dx1600 and you run the rig on ssb the cap will discharge under peak load giving you a higher average output. Any comments? (and I mean REAL comments) A one farad capacitor can only supply one amp for one second at one volt. Hardly worth the expense. It can only prevent a voltage drop on the first few peaks of a SSB modulated signal. It's usefulness would be almost totally drained after speaking just one appropriate word, pointless. Then there is not much point in using them in any kind of DC power supply, is there? Of course there is. Do the math, Tnom: A good car battery has, on the average, an source impedance of around 0.01 ohms (dropping 1 volt per 100 amps, which is a darn good battery). Ten feet of #8 AWG has a DC resistance of 0.0063 ohms, and we'll just assume that the negative lead is grounded at 0 ohms. So the total source impedance at the input of the amp is 0.0163 ohms. Now take an amp that can do 500 watts PEP. Assuming 50% efficiency, that means it can draw a maximum of 79.4 amps @ 12.6 volts. But since the source impedance is 0.0163 ohms, the voltage is going to drop 1.3 volts on the peaks, reducing the peak output by 50 watts or more. This is a type of soft-clipping and can result in some significant AF -and- RF distortion. And that's not considering the temperature coefficient of copper, which shows more resistance as it warms up from carrying lots of current, making the situation worse. Adding caps at the power input leads of the amp can significantly reduce the source impedance of the power supply. It -can't- provide more power than the supply is capable of providing, but it -can- smooth the voltage ripple just like in any other type of power supply. And what if the vehicle is running? Do the math: If you have a 100 amp alternator (at 13.8 volts), it has a source impedance of .138 ohms, which is significantly higher than the battery, so it's not going to be much help. In fact, because it's going to be so heavily loaded, it's going to introduce some ripple into the power lines, ripple that can be reduced by using caps at the input of the amp. How much capacitance is needed? There is no easy equation. There are a number of factors, such as the source resistance of the battery and alternator, resistance of the wire, ESR of the capacitors, average modulation percentage, PEP watts, etc, etc. Because of the very low impedance required by the amp, low ESR is paramount. Despite the advertised claims, the 'monster' caps usually have an ESR of several ohms, much higher than is usable. Computer-grade electrolytics have a much lower ESR. Using many smaller caps in parallel is better than one big cap because the ESR is much lower. Those are just a few things to consider. But the general rule is to keep adding caps until they no longer make any improvement. I'm really suprised, Tnom. After all the times you have shot your mouth off and been proven wrong on technical topics, you -still- haven't learned to think before you speak. Maybe next time. ============= "...but I admitted I was wrong, Like a man! Something you and QRM have a problem with. You guys are wrong and you both know it and are both too small to admit it." ---- Twistedhed ---- ============= -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |