Abdul, Well ~
You're almost right . . . A typical RF Choke on a PCB is a certain length conductor (typically 1/4 wavelength), which is acting as an inductor, from one active part of an RF circuit (typically the Collector of an RF Transistor) to another part of the circuit, typically power (or sometimes ground), such that it is a "short" at DC, and isolated (or open) at a given frequency. Thus one can pass power thru the Choke to the Transistor, but it does not appear to be a short at RF frequencies. There are other applications, but this is probably the most common one you will find on a PCB, and is actually quite common today. Now - Go ask Protel how to make it . . . No, don't give us your version (which we have already seen here in the list), but go ask Protel how to make it. JaMi Smith -----Original Message----- From: Abd ul-Rahman Lomax [mailto:[EMAIL PROTECTED]] Sent: Wednesday, February 20, 2002 1:44 PM To: Protel EDA Forum Cc: JaMi Smith; JaMi Smith Subject: RF footprints At 12:42 PM 2/20/2002 -0800, JaMi Smith wrote: >(Go ahead, ask Protel what >an RF Choke is, and how to make one in Protel). Printed components tend to not have fixed sizes, unless they have fixed values or functions. If one wanted to make an RF choke footprint, one would have to have a separate footprint for each value, with variations on that for various choke parameters. Instead, one would provide a wizard for generating such parts; feed the wizard the PCB parameters -- which is already in the PCB file --, type of pattern, desired parameters, and the wizard would attempt to create a pattern that satisfied the conditions. I have in the past been given dimensions for creating series of certain narrowly defined parts, the dimensions came from work with a field solver or other similar programs. (I'm not an RF engineer, but I work closely with one.) All this would fit very nicely into the Protel mission, but it is not a simple piece of work. [EMAIL PROTECTED] Abdulrahman Lomax Easthampton, Massachusetts USA * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
