Post by thread:[PICLIST] [EE] Little math problem

I have here "RF Circuit Design" by Chris Bowick. In chapter 3, Impedance Matching, one of his solutions os pretty sketchy... I understand everything except the jump from 2 to 3...it seems to be missing some steps because I don't believe you can convert directly to polar notation from a product over sum. How does he jump from step 2 to 3? Xc = Capacitive Reactance Rl = Load Resistance 1. XcRl Z = ------- Xc + Rl 2. -j333(1000) = ------------ -j333 + 1000 3. = 315 at -71.58 degrees 4. = 100 - j3000 Ohms Thanks for any help... Brandon Irwin - end _____________________________________________________________ Get your free email here at http://www.e-ha.com -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

1) A bit of math, try to multiply iten 2 by (+j333+1000) / (+j333+1000) as both values are equal you are multiplying by one, so you don't change the original value. you will end with -j333(1000) * (+j333 +1000) = ------------------------------ (-j333 + 1000) * (j333 +1000) 111088900 - j333000000 = ----------------------------- 1110889 = 100 -j299.76 = 315 -71.58 degrees in polar notation Note: iten 4 has an error it's 100 -j299.76 (or -j300 by rounding) not -j3000 I assume you know complex number algebra, let me know if you need anything else. This book is really amasing, enjoy it. Regards Horta wich in polar form is {Original Message removed}

Have a look at articles 12 and 13 at http://www.hallikainen.org/rw/theory/ Harold On Thu, 17 Jan 2002 14:57:08 -0800 Brandon Irwin <spam_OUTbrandonTakeThisOuTE-HA.COM> writes: {Quote hidden}> I have here "RF Circuit Design" by Chris Bowick. > > In chapter 3, Impedance Matching, one of his solutions os pretty > sketchy... > > I understand everything except the jump from 2 to 3...it seems to be > missing some steps because I don't believe you can convert directly > to polar notation from a product over sum. > > How does he jump from step 2 to 3? > > Xc = Capacitive Reactance > Rl = Load Resistance > > 1. > XcRl > Z = ------- > Xc + Rl > > 2. > -j333(1000) > = ------------ > -j333 + 1000 > > 3. > = 315 at -71.58 degrees > > 4. > = 100 - j3000 Ohms > > > Thanks for any help... > > Brandon Irwin > > - > end > > > > > > > > > > > > _____________________________________________________________ > Get your free email here at http://www.e-ha.com > > -- > http://www.piclist.com hint: PICList Posts must start with ONE > topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: > ->Ads > > FCC Rules Online at http://hallikainen.com/FccRules Lighting control for theatre and television at http://www.dovesystems.com ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: dl.http://www.juno.com/get/web/. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics