[Boatanchors] Do Headphones Age-Away?

[1oldlens1]

I wrote a response  about magnetic headphones.  Crystal phones have very high impedance and are very sensitive but do deteriorate.   Crystal headphones, microphones, phone pickups,  are vulnerable to moderately high temperatures, humidity, mechanical shock.  Brush, who owned the patents,  made headphones for decades but it's very difficult to find any that work.  I have several in my collection but only one capsule that is still good.  Perhaps headphones are  more vulnerable than microphones. Old crystal mics are rare enough but phones seem almost nonexistent.  I don't know if any ceramic phones were made, like microphones they would tend to be more long lasting.  Because crystal phones do not pass DC unless they are bad they don't have a characteristic resistance as magnetic or moving coil phones do.  The impedance of Brush phones was on the order of 100k per phone.  Unlike magnetic phones which are usually connected in series crystal phones must be in parallel to work.Sent from my Galaxy
-------- Original message --------From: Ron VE8RT <ve8rt at yknwt.ca> Date: 8/12/22  10:42 PM  (GMT-08:00) To: boatanchors at mailman.qth.net Subject: Re: [Boatanchors] Do Headphones Age-Away?   As no one has replied yet, I think that this may be helpful:https://en.wikipedia.org/wiki/Crystal_earpiecehttps://www.antiqueradios.com/forums/viewtopic.php?t=172739  If the earpiece is made using rochelle salts then yes they dodeteriorate (more rapidly in a humid environment) over time.  It is also a problem with antique microphones.  I would not be able to help with the question as to whether anythingcan be done about it.  Ron VE8RT VE8TEAOn Fri, 12 Aug 2022 22:57:53 -0500David Stinson <arc5 at ix.netcom.com> wrote:> I have a set of Featherlight 12,000 Ohm headphones> I've had since I was a young boy.  They were "sensitive"> for crystal radio sets, giving lots of volume (for phones).> Now, they're pretty weak.> Is anyone familiar with this "aging" of Hi-Z phones,> why it happens and if anything can be done about it?> > -- > This email has been checked for viruses by Avast antivirus software.> www.avast.com> ______________________________________________________________> Boatanchors mailing list> Home: http://mailman.qth.net/mailman/listinfo/boatanchors> Help: http://mailman.qth.net/mmfaq.htm> Post: mailto:Boatanchors at mailman.qth.net> > List Administrator: Gary Harmon, K5JWK> ** For Assistance: gharmon at idworld.net **> > > This list hosted by: http://www.qsl.net> Please help support this email list: http://www.qsl.net/donate.html> Message delivered to ve8rt at yknwt.ca -- Ron VE8RT <ve8rt at yknwt.ca>______________________________________________________________Boatanchors mailing listHome: http://mailman.qth.net/mailman/listinfo/boatanchorsHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:Boatanchors at mailman.qth.netList Administrator: Gary Harmon, K5JWK** For Assistance: gharmon at idworld.net **This list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.htmlMessage delivered to 1oldlens1 at ix.netcom.com