I have used 1N4007 diodes for this purpose and had no trouble! The last relay I took care of was the keying relays in the old Navy "TCS-12" transmitter I have. If you get across the key contacts when you are sending, the collapsing relay coil fields will give you quite a belt! Diode installed and no more problems!
73, Sandy W5TVW ----- Original Message ----- From: "Jack Smith" <jack.sm...@cliftonlaboratories.com> To: "'Elecraft'" <elecraft@mailman.qth.net> Sent: Wednesday, April 08, 2009 1:22 PM Subject: [Elecraft] Can a 1N4007 Be an Effective Relay Snubber? > To answer, I hope definitively, the question "is a 1N4007 power diode > too slow to be used as a relay coil snubber," I've updated my December > 2007 diode turn-on time measurements with data taken this morning > showing the effectiveness of (a) no snubber; (b) 1N4148 snubber and (c) > 1N4007 snubber with a typical small relay switched by a 2N7000 MOSFET > transistor. I've also looked at the how much the relay release time > lengthens when a snubber is added. (Of course, the specifics are > dependent upon the particular relay but the concepts are similar.) > > The details are at > http://www.cliftonlaboratories.com/diode_turn-on_time.htm > > The "Cliff's Notes" version is that the turn-on (note I said turn-on, > not turn-off) time of a 1N4007 diode is sufficiently fast to be a very > effective relay snubber. The data also shows that a diode or MOV or > other technique should be used to control inductive field decay voltages. > > Jack K8ZOA > www.cliftonlaboratories.com > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html -------------------------------------------------------------------------------- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.285 / Virus Database: 270.11.47/2047 - Release Date: 04/08/09 05:53:00 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
