This topic greatly interests me, because I have never found saturation or non-linearity in typical cores an issue.
This might be an opportunity to explore something new that I have never seen. ----- Original Message ----- From: "David Cutter" <[email protected]> To: "Geoffrey Mackenzie-Kennedy" <[email protected]> Cc: "Elecraft Discussion List" <[email protected]> Sent: Friday, June 18, 2010 9:47 AM Subject: Re: [Elecraft] K3 Low Pass Question > Hi Geoff > > I didn't know that about small cores, but, if I were to take on this idea, > I > would use the biggest I could get in there, which is around 45mm. > > There's a local radio station on medium wave which has given me grief in > the > past, (pre K3 mind you) and I could change it into a high pass filter just > for that. > > Come to think of it, I wonder if I could make such a filter for use with > the > MFJ259; that might be a better idea. > > David > G3UNA > > > >> David, >> >> A Low Pass filter cutting off above 6m is useful here, because our not so >> local FM BC station operates just above 100 MHz. >> >> I suggest that if you do convert a LPF, do not use small toroidal >> inductors (unless "air wound") if the filter is to be used between a >> receiver and an antenna feeder. Small cores can create IMD problems ftom >> BC stations etc, which is one reason why the solenoid type of inductor is >> used. >> >> 73, >> >> Geoff >> GM4ESD >> >> >> David Cutter wrote on Friday, June 18, 2010 9:27 AM: >> >>> I was idly wondering if I should convert them to something useful, >>> perhaps >>> to a band pass filter. There's room to fit small toroid inductors >>> instead >>> of the solenoid types. Then again, with the Elecraft line up I probably >>> wouldn't benefit much, but it would be an interesting project. >> >> >> > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
