re:[AMRadio] Telephone Wiring RFI Treatment
Tom Clarke NATOPS Program Support USN/USMC National Airworthiness Office Naval Air Systems Command, AIR-4.0P (301) 995-3793/DSN 995-3793 Fax: (301) 757-6599 Cell (301) 904-2053 [EMAIL PROTECTED] Here's one for those wishing a break from the current hot topic! I need to do some maintenance on the telephone wiring in my house in order to cure a hum that is now constant on all phones. While I'm at it, I'd like to take appropriate measures to eliminate, or at least reduce the rfi that occurs whenever I operate on 80 or 40 meters with any mode. Which ferrite beads or filtering should I use, and should I place any such devices on the house side of the entry box rather than, or in addition to at the connection point for each phone? The rfi was present before the hum appeared, so I doubt curing the hum will cure the rfi, although it certainly might at least reduce it. Mike Duke, K5XU American Council of Blind Radio Amateurs ---tom sez- Hi Mike, The last time I had hum on the phone it was caused by a water intrusion problem on the telco line outside the house. The way to check if it is your problem or theirs you may have already gone through this drill, sorry), is to plug a phone into the interface box on the outside of the house, which will isolate all the house wiring from the telco line. If there is hum, give the telco folks a call. If the hum is inside, start isolating things inside until you find it. Good luck in your search. 73 Tom/W4OKW __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
[AMRadio] Telephone Wiring RFI Treatment
Here's one for those wishing a break from the current hot topic! I need to do some maintenance on the telephone wiring in my house in order to cure a hum that is now constant on all phones. While I'm at it, I'd like to take appropriate measures to eliminate, or at least reduce the rfi that occurs whenever I operate on 80 or 40 meters with any mode. Which ferrite beads or filtering should I use, and should I place any such devices on the house side of the entry box rather than, or in addition to at the connection point for each phone? The rfi was present before the hum appeared, so I doubt curing the hum will cure the rfi, although it certainly might at least reduce it. Mike Duke, K5XU American Council of Blind Radio Amateurs __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
Re: [AMRadio] Telephone Wiring RFI Treatment
At work, we've had some success with K-Com filters, both wired and plug-in. -- Original message -- From: Mike Duke, K5XU [EMAIL PROTECTED] Here's one for those wishing a break from the current hot topic! I need to do some maintenance on the telephone wiring in my house in order to cure a hum that is now constant on all phones. While I'm at it, I'd like to take appropriate measures to eliminate, or at least reduce the rfi that occurs whenever I operate on 80 or 40 meters with any mode. Which ferrite beads or filtering should I use, and should I place any such devices on the house side of the entry box rather than, or in addition to at the connection point for each phone? The rfi was present before the hum appeared, so I doubt curing the hum will cure the rfi, although it certainly might at least reduce it. Mike Duke, K5XU American Council of Blind Radio Amateurs __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
Re: [AMRadio] Telephone Wiring RFI Treatment
My problem with this has always been keeping RF out of the computer speakers on 40M. Its the only band I seem to have RF problems with and it comes regardless whether I'm running low power or QRO. Any suggestions would be greatly appreciated. Mod-U-Lator, Mike(y) W3SLK __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
Re: [AMRadio] Telephone Wiring RFI Treatment
Since the problem is only there on 40 meters, one or both speaker leads may be resonant at the frequency used. Try ferrite cores on the leads or change the lead length making sure they are nor resonant on any of the ham bands you use. 73, John, W4AWM My problem with this has always been keeping RF out of the computer speakers on 40M. Its the only band I seem to have RF problems with... __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
Re: [AMRadio] Telephone Wiring RFI Treatment
Mike - I was successful getting rid of RF in my desktop computer speakers by using a split ferrite core choke from MFJ by wrapping about four turns of the speaker leads around the choke then closing the choke. Never have rf into the computer speakers now when using any rig or even when using my SB-200 at full power. It's worth a try. 73, Larry KC8JX --- [EMAIL PROTECTED] wrote: Since the problem is only there on 40 meters, one or both speaker leads may be resonant at the frequency used. Try ferrite cores on the leads or change the lead length making sure they are nor resonant on any of the ham bands you use. 73, John, W4AWM Mike W3slk wrote: My problem with this has always been keeping RF out of the computer speakers on 40M. Its the only band I seem to have RF problems with and it comes regardless whether I'm running low power or QRO. Any suggestions would be greatly appreciated. Mod-U-Lator, Mike(y) W3SLK __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
RE: [AMRadio] Telephone Wiring RFI Treatment
Try www.sandman.com. Best site I know of for telephone related anything! Also make sure you still have your twisted pair leads twisted all the way up to their terminations and no phone wiring running parallel to power lines, TV satellite cables, etc. Any place you have to cross other wiring with phone lines, run them perpendicular to each other. Said another way, make sure telephone lines are run with up-to-date Category 3 or better twisted pair wire and cross other wires and cables at 90 degree angles. Best Regards, Steve White, W5SAW SW Commercial Electronics mailto:[EMAIL PROTECTED] Whenever we're afraid, it's because we don't know enough. If we understood enough, we would never be afraid. -- Earl Nightingale -Original Message- From: Mike Duke, K5XU [mailto:[EMAIL PROTECTED] Sent: Sunday, December 17, 2006 12:57 PM To: Discussion of AM Radio Subject: [AMRadio] Telephone Wiring RFI Treatment Here's one for those wishing a break from the current hot topic! I need to do some maintenance on the telephone wiring in my house in order to cure a hum that is now constant on all phones. While I'm at it, I'd like to take appropriate measures to eliminate, or at least reduce the rfi that occurs whenever I operate on 80 or 40 meters with any mode. Which ferrite beads or filtering should I use, and should I place any such devices on the house side of the entry box rather than, or in addition to at the connection point for each phone? The rfi was present before the hum appeared, so I doubt curing the hum will cure the rfi, although it certainly might at least reduce it. Mike Duke, K5XU American Council of Blind Radio Amateurs __ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
