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Message |
    
Alleycat
Junior Member
Username: Alleycat
Post Number: 16
Registered: 3-2005
| | Posted on Friday, June 03, 2005 - 12:09 pm: | 
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I have not tried it yet but I think it could work. Run the correct wire from the headphone port on the transceiver to the Aux. port on a stereo that has a Graphic Equalizer and then listen thru the stereo speakers or headphones. Use the equalizer to remove some of the noise above and below the voice you are trying to hear. My old Yaesu FRG-7 receiver has a switch for high, normal and low tones and it helps out quite a bit some times. Might also be able to use a computer that has I-Tunes or something like it with an equalizer and then listen thru the computer. My computers creates so much noise on most all of my radios that I don't think I could do this and remove the noise from the computer itself.
Any ideas or thoughts?
Thanks, Alleycat KI4KHT |
Bruce
Senior Member
Username: Bruce
Post Number: 2789
Registered: 9-2003
| | Posted on Friday, June 03, 2005 - 2:36 pm: |
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allycat on the internet is a shairwhere DSP program for your sound card see if you can find it and play with that
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Bruce
Senior Member
Username: Bruce
Post Number: 2790
Registered: 9-2003
| | Posted on Friday, June 03, 2005 - 2:52 pm: |
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Start here
http://www.dxzone.com/catalog/Software/DSP/index.shtml |
Alleycat
Junior Member
Username: Alleycat
Post Number: 18
Registered: 3-2005
| | Posted on Monday, June 06, 2005 - 3:18 pm: |
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Thanks for the info. Bruce. I may try out some of it. The real problem is all of the noise coming from the computers. If someone in the house here is on DSL you can forget the radios. I am just wondering if anyone has tried hooking up to an old stereo that has an equalizer to remove some of the noise above and below someones voice transmission. I don't have a stereo with an equalizer anywhere close to my radios at this time so it would be a project to get one close to where I could use it and see if it works.
Thanks again, Alleycat KI4KHT |
Nobodyknows
Junior Member
Username: Nobodyknows
Post Number: 19
Registered: 4-2005
| | Posted on Monday, June 06, 2005 - 4:03 pm: |
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Alleycat,
My Base radio (Cobra 148) is sitting ontop of my computer and the DSL Modem is 11 inches away from CB/Comp setup and I have ZERO noise/static from anything and I always run comp on and CB on. I think you should be able to cure any noise on your end, Grounding and maybe you have leaky coax?
Also you can try a cheap mobile amp/equalizer into an external speaker. Swapmeets are thick with used mobile amps/equalizers for like 5 bucks a hit. |
Bruce
Senior Member
Username: Bruce
Post Number: 2815
Registered: 9-2003
| | Posted on Monday, June 06, 2005 - 6:37 pm: |
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Im on DSL and your right it causes me grief too. |
Nobodyknows
Junior Member
Username: Nobodyknows
Post Number: 20
Registered: 4-2005
| | Posted on Monday, June 06, 2005 - 11:33 pm: |
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Bruce, I set my DSL modem ontop of my CB as a test, I can't even force it to interfere with the radio. |
Hollowpoint445
Intermediate Member
Username: Hollowpoint445
Post Number: 364
Registered: 6-2004
| | Posted on Tuesday, June 07, 2005 - 1:49 pm: |
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My DSL modem doesn't cause me any grief either. My computer monitors are the main noise source that I have to battle.
When I worked at an ISP we would have people with connection difficulties wrap a shoe box with foil and put the DSL modem inside (temporarily) to see if the connection problem disappeared. Often it did and we could usually assume it was an issue with the switching power supply of the monitor that was causing the interference. Naturally they wouldn't believe us until they used the foil box and the interference went away.
You could use the same method to control the interference from the modem. Just make sure you have some ventilation slits in the top and sides of the box. Grounding the foil will help a great deal too.
A short anecdote - A customer didn't believe it would have any effect so he refused to do it. It turned out he just didn't want to take the time to wrap a box in foil so I asked him if he had any foil pouches, metal boxes or anything metal that the modem would fit inside just for a temporary check. He was a photographer and had lead lined bags for transporting film. Put the modem in there and his connection problems disappeared. After that he believed me that his magnificent Apple monitor was causing the interference and he moved the modem 25' away from his desk with a longer lan cable. I called him back 3 days later and he had no more connection issues.
My own DSL modem is less than 3' from my NID and installed with a NID splitter. It's more than 10' from the nearest monitor and I have no problems with my connection. |
Bruce
Senior Member
Username: Bruce
Post Number: 2822
Registered: 9-2003
| | Posted on Tuesday, June 07, 2005 - 8:19 pm: |
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mine is worst at 50 mhz ( 6 meters ) |
Coyote
Intermediate Member
Username: Coyote
Post Number: 236
Registered: 11-2004
| | Posted on Tuesday, June 07, 2005 - 10:33 pm: |
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Are we talking about wireless DSL modems here? |
Bruce
Senior Member
Username: Bruce
Post Number: 2824
Registered: 9-2003
| | Posted on Wednesday, June 08, 2005 - 6:52 am: |
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yes |
Alleycat
Junior Member
Username: Alleycat
Post Number: 20
Registered: 3-2005
| | Posted on Wednesday, June 08, 2005 - 1:23 pm: |
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My DSL is running on an Ethernet cable to all computers. I don't have wireless, Airport for Macs, installed in any of my computers. When any of the cables are plugged into the Westell Wirespeed modem it sounds like someone is playing 4 note scales up and down as I scan thru 6 Meters (50-54mhz). The computer that the cable is hooked up to does not even have to be on or in use. I don't hear any of the tones on the CB.
The white noise from the computers I can hear on all receivers. The computers I am talking about are desk top iMacs. I can tell the difference when the track ball is being used or if my wife is scrolling up or down a page. This noise is different from the noise from the computer just being on. The noise is not loud but just there in the background. My lap top iBook does not cause much if any noise unless the DSL is hooked up.
Has anyone had a chance to see if an equalizer helps to clean up received signals?
Back later, Alleycat KI4KHT |
Bruce
Senior Member
Username: Bruce
Post Number: 2827
Registered: 9-2003
| | Posted on Wednesday, June 08, 2005 - 1:42 pm: |
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im going to play with beads on the modem wire to fix some of this ..... i hope. |
Hollowpoint445
Intermediate Member
Username: Hollowpoint445
Post Number: 368
Registered: 6-2004
| | Posted on Wednesday, June 08, 2005 - 5:59 pm: |
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I've never heard this, but I don't play with 6M very much.
I've got a Westell Wirespeed too. About what frequency do you hear the tones on, and in what mode? I'll see what I can find out about it. Also, are the tones worse when the modem is rebooted? I've often heard tones on telephone lines while talking with customers, but only when the modem is sweeping it's bandwith while negotiating a connection. Usually they go away when the connection is established.
If you have DSL on a telephone number that you use for voice as well - and you probably do because "lineshare" is the most common type of DSL installation - it's very important that EVERY SINGLE DEVICE on that line is filtered with the single exception of the DSL modem. That includes all telephones, answering machines, caller ID boxes, dial up modems, satellite TV receivers, cable boxes that use phone lines for pay per view, security systems, external or auxillary ringers, phoneline door bells, phone line intercoms, wireless phone jacks (they directly interfere with DSL anyway), and anything else that uses the phone line.
There are two ways to do this. The most common is to put a small filter in each telephone jack and then plug whatever was plugged into the jack into that filter. These filters are directional, and they MUST be plugged into the jack and not into the back of the telephone. The other way is to install a NID splitter which would set aside a jack for the DSL modem only, and then the rest of your phone system is filterd by the NID splitter.
Unfiltered devices can rectify the DSL signal and cause audible tones on the telephone line. It's possible that an unfiltered device could be radiating this interfering signal that you're hearing.
In the 4 years that I did DSL support I never heard of a DSL modem causing any kind of RF interference. Actually, DSL modems are quite sensitive to RF interference themselves. Living near an AM broacast antenna array virtually assures that DSL won't work on your telephone line. |
Bruce
Senior Member
Username: Bruce
Post Number: 2830
Registered: 9-2003
| | Posted on Thursday, June 09, 2005 - 6:59 am: |
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I hear tones all over 6 meters and when the wireless modem is off they go away.
SOOOOO time to go find out why. |
Tech237
Moderator
Username: Tech237
Post Number: 149
Registered: 4-2004
| | Posted on Thursday, June 09, 2005 - 9:46 am: |
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Been running several filter/dsp programs on my computer for the last 5 or years. They work well in some cases and not so well in others.
Some are too selective in that you only have a choice of two or three settings (CW, SSB or Music - I think one program I didnt keep had). Try the various ones around. I found mine at www.simtel.net |
Hollowpoint445
Intermediate Member
Username: Hollowpoint445
Post Number: 373
Registered: 6-2004
| | Posted on Thursday, June 09, 2005 - 2:51 pm: |
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That might explain why I don't have that noise Bruce - I don't use WiFi because it's not as secure, it's not as fast, I have a 2.4 GHz cordless phone and I don't need anymore RF than I already have. |
