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I'll add to that those wonderful "Monster caps" that are those High farad
values of 5, 15, and 50 Farads (Thanks alot Alumapro, and Pheonix Gold) are junk. Even if the measured or stated (ESR) is low. The other problem is ESL, equivlent series inductance. The ESL is kind of like a the responsecurve of a VSWR curver through the frequency rage of a Antenna. The ESL changes with freq. Now that may be low with a DC circuit. But the minute you start fluctuating that current and voltage, the ESL Will start to rear it ugly head. Remember L = Inductace is the Opposition to current flow. If you really want some good imput on this hit up Carsound.com Forums and look up under Richard Clarks Archived topis for Capacitors. "Frank Gilliland" wrote in message ... In , "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) Even though you are a troll, you actually raise a good point here. Now I'm assuming you meant that the capacitor is connected in parallel with the power supply leads, because if it were connected in series you would get no power. In an SSB amp the RF power follows the audio, and will therefore have a current draw that varies at audio frequencies. A capacitor placed across the power leads of the amp, when combined with the inherent resistance of the wires from the battery, creates a simple low-pass filter which will help smooth out those 'audio' peaks. The bigger the amp, the bigger the cap. And keep the leads from the amp to the cap as short as possible. BTW, this type of filter won't do much in AM service since the current drawn by the amp in AM is fairly steady (at least it -should- be, i.e, it's not amplifying a signal loaded with overmodulation and 'swang'). But it -will- filter out noise from the power supply. A word about those 'moster caps' for audio amps: Most of them have a high equivalent series resistance (ESR) which defeats the purpose of using them. They behave more like a rechargeable battery than a capacitor. Locate your local computer junkyard and get some of those big electrolytics from the mainframe power supplies. Typically, just one 100,000 uFd aluminum electrolytic has a lower ESR than a 1.0 farad 'monster' cap. Also remember that you can reduce the ESR by putting capacitors in parallel. Ten 10,000 uFd caps in parallel will have a much better ESR, and therefore much better filtering ability, than one 100,000 uFd capacitor of the same type, even though the total mFd value is the same. ============= "...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! =----- |