Home |
Search |
Today's Posts |
#91
![]() |
|||
|
|||
![]() "itoldyouiamnotiamnotgeorge" wrote in message ... "U Know Who" wrote in news:6TCbe.43676$hu5.16593 @tornado.texas.rr.com: "itoldyouiamnotiamnotgeorge" wrote in message ... Frank Gilliland wrote in : On 25 Apr 2005 19:48:48 -0700, "Cliff" wrote in . com: If a CB radio is legal on wattage out, he doesn't have to clean up that image on any of older TV models. Older TV models are horrific in picking up 'legal transmissions' The TV/computer owner wil need to put some filters inline to take care of the problem if the CB is legal. Televisions have always had problems with CB radios because the second harmonic falls right on channel 2. But that second harmonic is supposed to be supressed (filtered) to a point where it's effect is negligible. A stock, unmodified, untweaked radio will usually not cause interference to a TV unless you mount the antenna right next to the set. The problem is the golden screwdrivers and internet techs who tweak & peak their radios for modulation and/or power without regard to the resulting increase of harmonics. Even if power is kept to the legal limit, the modulation limiter can be modified for overmodulation, and therefore cause a big increase in harmonics. This is why modification of the radio is illegal. And modification of the radio voids your authorization to use it, regardless of the RFI suseptibility of a TV. Now this is the Old Frank that I have come to know and love ... 2 thumbs up Frank!!! Awww! Ain't just the sweetest thing you've ever written? No that i ****ed your ex- old lady was better. More power to ya, bud! |
#93
![]() |
|||
|
|||
![]()
On Wed, 27 Apr 2005 10:22:40 -0500, "Chad Wahls"
wrote in : snip Most often, even wahat you consider "high end" cards do not have the audio sheild grounded properly. Very good point. Some cards have shield connectors that are DC isolated from the chassis to prevent ground loops with other audio equipment. In such cards the shield is coupled to chassis ground with caps, but line noise can be a problem (and the cap must be shorted) because the caps may not large enough to fully shunt low frequencies. But the caps do shunt RF very well, and if they can keep the local AM broadcast stations out of the soundcard then the neighbor's legal CB radio shouldn't be a problem. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#94
![]() |
|||
|
|||
![]() "Frank Gilliland" wrote in message ... On Wed, 27 Apr 2005 10:22:40 -0500, "Chad Wahls" wrote in : snip Most often, even wahat you consider "high end" cards do not have the audio sheild grounded properly. Very good point. Some cards have shield connectors that are DC isolated from the chassis to prevent ground loops with other audio equipment. In such cards the shield is coupled to chassis ground with caps, but line noise can be a problem (and the cap must be shorted) because the caps may not large enough to fully shunt low frequencies. But the caps do shunt RF very well, and if they can keep the local AM broadcast stations out of the soundcard then the neighbor's legal CB radio shouldn't be a problem. Problem is that they don't do all that well with AM Broadcast. When I was a conglomo radio engineer we had a 50K FM and a 500W AM in a residential area. I would get complaints-o-plenty of the AM coming thru computer speakers, cheapo HT systems and phones. Of course we had to do what we could to eliminate the problem and usually I would pull the sound card, DC ground it with 1 ohm 1/4W resistors and the problem went away. 90% of my problems called in were ratified with proper grounding. Fortunately most of the construction in the area is newer as that tower used to be outside city limits but due to urban sprawl it is no longer. As for my personal soundcards I use pro models with a separate breakout box that's balanced. The other card in that computer and other computers in the house are SB audigy models with the mini jacks removed and XLR whips out in their place. This whip then goes to a breakout box with 6 Jensen transformers in it 4 for output and 2 for input. The mic input is shorted down permanently. I have zero noise problems, if you have an Audigy card it does sound good! You just have to help it out ![]() The transformers....... When radio engineering and upgrading EAS systems in all the stations I found that all the old receivers that we were throwing out were loaded with Jensen transformers! What a salvage find!!!!! I had many-o-dumpster diving missions, then adopted a Chad's gotta pilfer it pile. Lots of transformers and power supplies were gutted ![]() Chad |
#95
![]() |
|||
|
|||
![]()
Yep, I do get the drift. Beautifully illustrated with a great analogy.
You ought write that up in a neat letter to your local editor concerning the (un)Patriot Act,,or even a national editor. |
#96
![]() |
|||
|
|||
![]()
On Thu, 28 Apr 2005 11:27:29 -0400, (I
AmnotGeorgeBush) wrote in : Yep, I do get the drift. Beautifully illustrated with a great analogy. You ought write that up in a neat letter to your local editor concerning the (un)Patriot Act,,or even a national editor. Thank you. Plagiarize it as you see fit. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#97
![]() |
|||
|
|||
![]()
On Thu, 28 Apr 2005 09:11:08 -0500, "Chad Wahls"
wrote in : "Frank Gilliland" wrote in message .. . On Wed, 27 Apr 2005 10:22:40 -0500, "Chad Wahls" wrote in : snip Most often, even wahat you consider "high end" cards do not have the audio sheild grounded properly. Very good point. Some cards have shield connectors that are DC isolated from the chassis to prevent ground loops with other audio equipment. In such cards the shield is coupled to chassis ground with caps, but line noise can be a problem (and the cap must be shorted) because the caps may not large enough to fully shunt low frequencies. But the caps do shunt RF very well, and if they can keep the local AM broadcast stations out of the soundcard then the neighbor's legal CB radio shouldn't be a problem. Problem is that they don't do all that well with AM Broadcast. When I was a conglomo radio engineer we had a 50K FM and a 500W AM in a residential area. I would get complaints-o-plenty of the AM coming thru computer speakers, cheapo HT systems and phones. Sounds like we had similar jobs -- do the daily checks, fill out the daily reports, then spend the rest of the day making cables, cleaning cart machines and waiting for something to break? Of course we had to do what we could to eliminate the problem and usually I would pull the sound card, DC ground it with 1 ohm 1/4W resistors and the problem went away. 90% of my problems called in were ratified with proper grounding. Fortunately most of the construction in the area is newer as that tower used to be outside city limits but due to urban sprawl it is no longer. As for my personal soundcards I use pro models with a separate breakout box that's balanced. The other card in that computer and other computers in the house are SB audigy models with the mini jacks removed and XLR whips out in their place. This whip then goes to a breakout box with 6 Jensen transformers in it 4 for output and 2 for input. The mic input is shorted down permanently. I have zero noise problems, if you have an Audigy card it does sound good! You just have to help it out ![]() I use the Extigy -- it's great because you can locate the box some distance away from the noisy computer and ground it directly to the mixer. But for complaints to the station, I got them to order a huge box of 4" jumpers that have pigtails to the shield. Just plug them into the soundcard (or whatever audio equipment is getting the interference), screw the pigtail to the chassis, and 'presto' -- problem solved. No invasive surgery, and you're out of the house in a matter of minutes. The transformers....... When radio engineering and upgrading EAS systems in all the stations I found that all the old receivers that we were throwing out were loaded with Jensen transformers! What a salvage find!!!!! No kidding! I had many-o-dumpster diving missions, then adopted a Chad's gotta pilfer it pile. Lots of transformers and power supplies were gutted ![]() Those old Bogen and Rauland paging amps have some pretty sweet transformers, too. One of these days we gotta exchange inventory lists of our scrounge bins. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#98
![]() |
|||
|
|||
![]()
FRANK, U B CORRECT ON THIS.
|
#99
![]() |
|||
|
|||
![]()
"Steveo" wrote...
Vinnie S. wrote: Here is something I learned. My 2M/440 handheld sets off my paper shredder when it is within 3 feet. I hope your parakeet doesn't land on it as you key up. What's for breakfast... Shredded Tweet :~) Regards, Peter http://www.citizensband.radiouk.com/ |
#100
![]() |
|||
|
|||
![]()
"Peter" wrote:
"Steveo" wrote... Vinnie S. wrote: Here is something I learned. My 2M/440 handheld sets off my paper shredder when it is within 3 feet. I hope your parakeet doesn't land on it as you key up. What's for breakfast... Shredded Tweet :~) Regards, Peter http://www.citizensband.radiouk.com/ OH! please tip your waitress, he'll be here all week! |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
197 English-language HF Broadcasts audible in NE US (23-NOV-04) | Shortwave | |||
Amateur Radio Newslineâ„¢ Report 1415 Â September 24, 2004 | Policy | |||
Amateur Radio Newsline™ Report 1379 – January 16, 2004 | Broadcasting | |||
Amateur Radio Newsline™ Report 1379 – January 16, 2004 | Policy | |||
Amateur Radio Newsline™ Report 1379 – January 16, 2004 | Dx |