My cores arrived yesterday. I haven't done any electrical testing on them yet, but mechanically they appear to be fine. They were not "crumbly" as some were concerned about. I don't think they are as high quality as the fair rite cores I've used in the past, but this is based only on aesthetics (the amidon cores I received have some striations in the faces, and will mar fingers if you rub them). I don't think they will be a problem in service.
My known-to-be fair rite cores from a previous mouser order did not show any striations in the faces of the cores, nor did anything come off on fingers when they were rubbed. They were also #31 mix though, so that might be part of it. I don't have any other #61 cores laying around to try with a "rub test". It looks to me that amidon has either switched suppliers or their supplier has corrected the problem that was reported earlier. -Bill Sent from my iPad > On Aug 5, 2014, at 3:29 PM, "Bill Wichers" <[email protected]> wrote: > > It sounds like they weren’t properly fired from what he said about them > crumbling. That, at least, is an easier thing to look for than a messed up > mix. If they have poor QC on these things then I’d be concerned about the > “mix #61” not actually being mixed correctly resulting in the cores not > having the correct magnetic properties. If I have some time I can put > together a test setup for that and check the ones I have coming to be sure. > > That post looks to be several years old so hopefully Amidon has corrected the > problem, or otherwise switched suppliers. > > -Bill > > From: Mike Waters [mailto:[email protected]] > Sent: Tuesday, August 05, 2014 3:01 PM > To: Bill Wichers > Cc: topband > Subject: Re: Topband: Ferrite Cores > > It's certainly possible. > > You can read what he said and see photos at > http://forums.qrz.com/showthread.php?240056-Need-source-for-Cushcraft-R5-torroids&p=1882177#post1882177 > > 73, Mike > www.w0btu.com<http://www.w0btu.com> > > On Tue, Aug 5, 2014 at 1:54 PM, Bill Wichers > <[email protected]<mailto:[email protected]>> wrote: > Well, I should have them in a few days so I’ll check them out and report back > what I find. Maybe Greg just got some from a bad lot? > FT-240-61 cores. Amidon was $9/ea, Mouser (for the Fair Rite equivalent) was > $14/ea. > > Those were the SAME Amidon cores that Greg, W9GB said were crumbly, cheap > Chinese junk and completely unusable. See my previous post. > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband
