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Antenna Whine?
I drive a 9900 International. I am getting a loud whine in the CB speaker,
but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. |
"Randy" wrote:
I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. Sounds like not enough ground on your antenna. How's your swr? -- http://www.allpar.com/mopar.html |
In , "Randy" wrote:
I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. What brand/model radio are you using? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Steveo" wrote in message ... "Randy" wrote: I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. Sounds like not enough ground on your antenna. How's your swr? -- http://www.allpar.com/mopar.html swr is ~ 3 I am just learning about CB radios. I know the antennas are using plastic inserts to keep them from being grounded. I am using Firestik II antennas and have not tried adjusting them yet. I thought I needed to eliminate the whine first. This International has a fiberglass top making for a bad ground plane, from what I have been reading. That is about all I know of my situation. |
"Frank Gilliland" wrote in message ... In , "Randy" wrote: I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. What brand/model radio are you using? I am using a Cobra 29 NW right out of the box. Antennas are 4' Firestiks II swr ~ 3 |
"Randy" wrote:
I am using a Cobra 29 NW right out of the box. Antennas are 4' Firestiks II swr ~ 3 swr - 3? you got problems and dual antenna's suck. Try using just one of them. -- http://www.allpar.com/mopar.html |
"Randy" wrote:
"Steveo" wrote in message ... "Randy" wrote: I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. Sounds like not enough ground on your antenna. How's your swr? -- http://www.allpar.com/mopar.html swr is ~ 3 I am just learning about CB radios. I know the antennas are using plastic inserts to keep them from being grounded. I am using Firestik II antennas and have not tried adjusting them yet. I thought I needed to eliminate the whine first. This International has a fiberglass top making for a bad ground plane, from what I have been reading. That is about all I know of my situation. There's no stupid questions, Randy. The first thing to make sure of is your antenna, it's just like any other electrical connection and it has to be right. Good ground and swr and separation from the body metal just for starters. Some of that noise can be from the electric fuel pump on certain vehicles. Get your swr down to 1.5 or less for starters. You'll have to process of eliminate for any static after you know your antenna is working properly. They do sell filters for some of that noise, it goes on your hot lead. Longer is better for antenna's..you can un-screw it without getting out of the truck if you mirror mount it. -- http://www.allpar.com/mopar.html |
In , "Randy" wrote:
"Frank Gilliland" wrote in message .. . In , "Randy" wrote: I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. What brand/model radio are you using? I am using a Cobra 29 NW right out of the box. Antennas are 4' Firestiks II swr ~ 3 Your SWR is high. High SWR isn't responsible for whine, but it is a good indicator of other problems. From what you said in your other post your cab roof is fiberglass, so you don't have any ground plane -at all- for your antenna. But even that isn't responsible for the whine. I suspect that the radio isn't very well grounded. The mounting bracket should be bolted directly to the dash or some other chassis metal, and the negative power lead should be as short as possible (inches) to the same. You can also try a noise filter on your positive power lead, and tap the wire as close to the radio as possible. That should eliminate your whine. It should also get your SWR down below 3. As for your antenna, you need to find a point on the rig where the antenna can be mounted directly to the chassis. A mirror mount is ok if the bracket and door are well grounded. A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). You could also try one of those 'no-ground-plane' antennas but don't expect great results. Ask around the watering holes and see what others have done. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Steveo" wrote in message ... "Randy" wrote: I am using a Cobra 29 NW right out of the box. Antennas are 4' Firestiks II swr ~ 3 swr - 3? you got problems and dual antenna's suck. Try using just one of them. -- http://www.allpar.com/mopar.html I had this same setup on another truck of the same year and model without any whine. That setup also had a fairly high swr but zero whine. Are you suggesting that because I have high swr that this is somehow allowing this whine to be picked up by the antennas? .. or maybe causing the whine? What is actually causing the whine? |
"Randy" wrote:
"Steveo" wrote in message ... "Randy" wrote: I am using a Cobra 29 NW right out of the box. Antennas are 4' Firestiks II swr ~ 3 swr - 3? you got problems and dual antenna's suck. Try using just one of them. -- http://www.allpar.com/mopar.html I had this same setup on another truck of the same year and model without any whine. That setup also had a fairly high swr but zero whine. Are you suggesting that because I have high swr that this is somehow allowing this whine to be picked up by the antennas? .. or maybe causing the whine? What is actually causing the whine? I'm suggesting perhaps your transmitting off just your coax, with your swr being 3. Start with your antenna problems, then fix the whine. -- http://www.allpar.com/mopar.html |
Frank Gilliland wrote:
A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). Don't see many of those in these parts, but it might work. -- http://www.allpar.com/mopar.html |
In , Steveo
wrote: Frank Gilliland wrote: A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). Don't see many of those in these parts, but it might work. It's not real popular, but I'm seeing it more and more -- probably due to the increasing number of plastic tractors on the road. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Frank Gilliland wrote:
In , Steveo wrote: Frank Gilliland wrote: A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). Don't see many of those in these parts, but it might work. It's not real popular, but I'm seeing it more and more -- probably due to the increasing number of plastic tractors on the road. See any on pickup trucks yet? -- http://www.allpar.com/mopar.html |
In , Steveo
wrote: Frank Gilliland wrote: In , Steveo wrote: Frank Gilliland wrote: A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). Don't see many of those in these parts, but it might work. It's not real popular, but I'm seeing it more and more -- probably due to the increasing number of plastic tractors on the road. See any on pickup trucks yet? Just on the back bumper, and not too many of those. Seems everyone is so paranoid about resale value these days that they are afraid to drill holes even in the bumper. My Dodge has a 9' whip mounted dead center on the roo-guard right above the winch, but I'm strange that way. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Your SWR is high. High SWR isn't responsible for whine, but it is a good indicator of other problems. From what you said in your other post your cab roof is fiberglass, so you don't have any ground plane -at all- for your antenna. But even that isn't responsible for the whine. I suspect that the radio isn't very well grounded. The mounting bracket should be bolted directly to the dash or some other chassis metal, and the negative power lead should be as short as possible (inches) to the same. You can also try a noise filter on your positive power lead, and tap the wire as close to the radio as possible. That should eliminate your whine. It should also get your SWR down below 3. As for your antenna, you need to find a point on the rig where the antenna can be mounted directly to the chassis. A mirror mount is ok if the bracket and door are well grounded. A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). You could also try one of those 'no-ground-plane' antennas but don't expect great results. Ask around the watering holes and see what others have done. I thought that because the whine went away when I disconnected the coax that the problem was not related to the power supply and one of those noise filters would not be of much use. My biggest obstacle is that this is a company truck. The CB, radio and TV are all using these antennas thru some kind of combiner. Running new coax would mean drilling holes in the cab. I am not sure how my boss would feel about this. If it were my truck I would rip it all out and start from scratch but I must do the best I can with what I have. The antennas are mirror mounts. I have been reading about grounding. I thought that two antennas actually were better on the fiberglass vehicles because they could create a ground plane between each other. My antennas use a plastic insert to keep them from being grounded to the mirrors. If I ground them would this short out the transmitter? I appreciate your feedback Frank, I know that it is difficult to diagnose something from a distance but I am willing to try anything except routing new coax. |
Frank Gilliland wrote:
In , Steveo wrote: Frank Gilliland wrote: In , Steveo wrote: Frank Gilliland wrote: A 9' whip on the front bumper isn't a bad choice either (don't forget to tie it back a bit so it doesn't flop around). Don't see many of those in these parts, but it might work. It's not real popular, but I'm seeing it more and more -- probably due to the increasing number of plastic tractors on the road. See any on pickup trucks yet? Just on the back bumper, and not too many of those. Seems everyone is so paranoid about resale value these days that they are afraid to drill holes even in the bumper. My Dodge has a 9' whip mounted dead center on the roo-guard right above the winch, but I'm strange that way. They don't call em' power-wagons for nothing! I had one on the back of my gmc for a little while, but it turned out to be a pain in the ass, so I went to a center roof mount Wilson. I can reach and un-screw it if I need to. It handles 300 watts nicely. -- http://www.allpar.com/mopar.html |
In , "Randy" wrote:
snip I thought that because the whine went away when I disconnected the coax that the problem was not related to the power supply and one of those noise filters would not be of much use. You said the noise is not present on your broadcast radio, which tells me that the noise isn't coming from the antenna. If the noise goes away when you disconnect the coax then it must be being picked up by the coax shield. If the coax shield were grounded then the CB would not hear the noise. Since the coax shield is connected to the chassis of the CB, that means the CB isn't grounded (by 'grounded' I mean an RF ground). The radio should be grounded by mounting it directly to the metal chassis and using a very short negative power lead. The noise filter helps prevent noise from any possible ground-loops or other RF feedback paths. My biggest obstacle is that this is a company truck. The CB, radio and TV are all using these antennas thru some kind of combiner. ......yikes! Running new coax would mean drilling holes in the cab. I am not sure how my boss would feel about this. If it were my truck I would rip it all out and start from scratch but I must do the best I can with what I have. Your boss wants you to deliver the payload in the shortest amount of time with the least amount of hassles. To do your job well, local communication with a good CB is -extremely- helpful, and almost essential for a long-haul driver. The antennas are mirror mounts. I have been reading about grounding. I thought that two antennas actually were better on the fiberglass vehicles because they could create a ground plane between each other. My antennas use a plastic insert to keep them from being grounded to the mirrors. If I ground them would this short out the transmitter? Dual antennas have no practical advantage over a single antenna in a mobile installation. They do not create a ground plane between them, nor do they work as a counterpoise to each other. They do look cool, but if I were you I would just use one and avoid the hassle. As for the antenna mount, the shield of the coax should be -well- connected to the chassis (ground-plane), and the center conductor to the antenna. The plastic insert is used to keep the two apart. If you disconnect the coax at the radio and check it with an ohmmeter (center conductor to the shield), it should be wide open; i.e, -not- shorted. I appreciate your feedback Frank, I know that it is difficult to diagnose something from a distance but I am willing to try anything except routing new coax. Don't spend -your- time or money -- convince your boss that you need a CB radio, then get him to have his contracted radio shop do a proper installation. That's what most trucking companies do, and I'm suprised your's doesn't. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Randy" wrote in message ... "Steveo" wrote in message ... "Randy" wrote: I drive a 9900 International. I am getting a loud whine in the CB speaker, but not in the radio speakers, even though they share the dual antennas. The whine increases and decreases with the rpms of the motor. After disconnecting the coax from the CB transceiver the whine is gone. Does this mean the coax or antennas are definitely the problem? ... or are they just picking up on a problem with the alternator? The coax will be extremely hard to replace, maybe impossible since this is a company truck. The alternator would probably be easier to repair. Any help to eliminate or even reduce the whine would be greatly appreciated. Sounds like not enough ground on your antenna. How's your swr? -- http://www.allpar.com/mopar.html swr is ~ 3 I am just learning about CB radios. I know the antennas are using plastic inserts to keep them from being grounded. I am using Firestik II antennas and have not tried adjusting them yet. I thought I needed to eliminate the whine first. This International has a fiberglass top making for a bad ground plane, from what I have been reading. That is about all I know of my situation. SWR's to high. Try a "no ground" type of antenna, get the SWR down below 2 or lower would be better. Landshark -- The world is good-natured to people who are good natured. |
"Frank Gilliland" wrote in message ... In , "Randy" wrote: snip I thought that because the whine went away when I disconnected the coax that the problem was not related to the power supply and one of those noise filters would not be of much use. You said the noise is not present on your broadcast radio, which tells me that the noise isn't coming from the antenna. If the noise goes away when you disconnect the coax then it must be being picked up by the coax shield. If the coax shield were grounded then the CB would not hear the noise. Since the coax shield is connected to the chassis of the CB, that means the CB isn't grounded (by 'grounded' I mean an RF ground). The radio should be grounded by mounting it directly to the metal chassis and using a very short negative power lead. The noise filter helps prevent noise from any possible ground-loops or other RF feedback paths. My biggest obstacle is that this is a company truck. The CB, radio and TV are all using these antennas thru some kind of combiner. .....yikes! Running new coax would mean drilling holes in the cab. I am not sure how my boss would feel about this. If it were my truck I would rip it all out and start from scratch but I must do the best I can with what I have. Your boss wants you to deliver the payload in the shortest amount of time with the least amount of hassles. To do your job well, local communication with a good CB is -extremely- helpful, and almost essential for a long-haul driver. The antennas are mirror mounts. I have been reading about grounding. I thought that two antennas actually were better on the fiberglass vehicles because they could create a ground plane between each other. My antennas use a plastic insert to keep them from being grounded to the mirrors. If I ground them would this short out the transmitter? Dual antennas have no practical advantage over a single antenna in a mobile installation. They do not create a ground plane between them, nor do they work as a counterpoise to each other. They do look cool, but if I were you I would just use one and avoid the hassle. As for the antenna mount, the shield of the coax should be -well- connected to the chassis (ground-plane), and the center conductor to the antenna. The plastic insert is used to keep the two apart. If you disconnect the coax at the radio and check it with an ohmmeter (center conductor to the shield), it should be wide open; i.e, -not- shorted. I appreciate your feedback Frank, I know that it is difficult to diagnose something from a distance but I am willing to try anything except routing new coax. Don't spend -your- time or money -- convince your boss that you need a CB radio, then get him to have his contracted radio shop do a proper installation. That's what most trucking companies do, and I'm suprised your's doesn't. Just so I am clear about one thing .... In all of these articles that I have been reading, when they talk about grounding the antenna, they are referring to a RF ground (ground plane) and not a physical ground? If for some reason the shield is not grounded would this be my problem? My boss will not care that this unit has a whine. I am not sure he would care whether it has a CB or not. I had to take the truck down to the shop last week to get the steer tires balanced, I had to pay for everything. He is not a bad guy ... just cheap! The unit might not be grounded very good. It sits in an upper header console, just strapped in not bolted. I will ground the unit and purchase a noise filter then adjust my antennas. I tried reading as many articles as I could but they all were saying the same things and some of that I could not understand. I thank you for your time. I will let you know if the problem persist after these changes. Thanks again |
You should be able to remove the plastic inserts where the antennas are
mounted. You may also have a problem with the splitter that allows the stereo and TV to use the same antennas. Maybe you can use one antenna for the CB and the other for everything else. As for the whine, I agree with everyone else. Once the antennas are working properly, it may go away. Chris "Randy" wrote in message ... "Frank Gilliland" wrote in message ... In , "Randy" wrote: snip I thought that because the whine went away when I disconnected the coax that the problem was not related to the power supply and one of those noise filters would not be of much use. You said the noise is not present on your broadcast radio, which tells me that the noise isn't coming from the antenna. If the noise goes away when you disconnect the coax then it must be being picked up by the coax shield. If the coax shield were grounded then the CB would not hear the noise. Since the coax shield is connected to the chassis of the CB, that means the CB isn't grounded (by 'grounded' I mean an RF ground). The radio should be grounded by mounting it directly to the metal chassis and using a very short negative power lead. The noise filter helps prevent noise from any possible ground-loops or other RF feedback paths. My biggest obstacle is that this is a company truck. The CB, radio and TV are all using these antennas thru some kind of combiner. .....yikes! Running new coax would mean drilling holes in the cab. I am not sure how my boss would feel about this. If it were my truck I would rip it all out and start from scratch but I must do the best I can with what I have. Your boss wants you to deliver the payload in the shortest amount of time with the least amount of hassles. To do your job well, local communication with a good CB is -extremely- helpful, and almost essential for a long-haul driver. The antennas are mirror mounts. I have been reading about grounding. I thought that two antennas actually were better on the fiberglass vehicles because they could create a ground plane between each other. My antennas use a plastic insert to keep them from being grounded to the mirrors. If I ground them would this short out the transmitter? Dual antennas have no practical advantage over a single antenna in a mobile installation. They do not create a ground plane between them, nor do they work as a counterpoise to each other. They do look cool, but if I were you I would just use one and avoid the hassle. As for the antenna mount, the shield of the coax should be -well- connected to the chassis (ground-plane), and the center conductor to the antenna. The plastic insert is used to keep the two apart. If you disconnect the coax at the radio and check it with an ohmmeter (center conductor to the shield), it should be wide open; i.e, -not- shorted. I appreciate your feedback Frank, I know that it is difficult to diagnose something from a distance but I am willing to try anything except routing new coax. Don't spend -your- time or money -- convince your boss that you need a CB radio, then get him to have his contracted radio shop do a proper installation. That's what most trucking companies do, and I'm suprised your's doesn't. Just so I am clear about one thing .... In all of these articles that I have been reading, when they talk about grounding the antenna, they are referring to a RF ground (ground plane) and not a physical ground? If for some reason the shield is not grounded would this be my problem? My boss will not care that this unit has a whine. I am not sure he would care whether it has a CB or not. I had to take the truck down to the shop last week to get the steer tires balanced, I had to pay for everything. He is not a bad guy ... just cheap! The unit might not be grounded very good. It sits in an upper header console, just strapped in not bolted. I will ground the unit and purchase a noise filter then adjust my antennas. I tried reading as many articles as I could but they all were saying the same things and some of that I could not understand. I thank you for your time. I will let you know if the problem persist after these changes. Thanks again |
"Chris" wrote in message nk.net... You should be able to remove the plastic inserts where the antennas are mounted. You may also have a problem with the splitter that allows the stereo and TV to use the same antennas. Maybe you can use one antenna for the CB and the other for everything else. As for the whine, I agree with everyone else. Once the antennas are working properly, it may go away. Chris If I remove the plastic inserts from the antenna mount, will that create a direct short when I am transmitting? I believe the splitter could be the problem also, like I said earlier if this my truck I would rip it all out and start from scratch. I did a little work ... swr @ 2.1. I just transmitted 9 miles. Whine still there ... might be louder. I am still wondering what is actually causing the whine i.e. alternator, fuel pump ....... maybe I need to look at the source of the whine rather than the ability to filter it out? |
The mounting bracket should be grounded to the truck and attached to the
coax sheild. There SHOULD be an insulator between the antenna and the bracket so leave it there. Chris "Randy" wrote in message ... "Chris" wrote in message nk.net... You should be able to remove the plastic inserts where the antennas are mounted. You may also have a problem with the splitter that allows the stereo and TV to use the same antennas. Maybe you can use one antenna for the CB and the other for everything else. As for the whine, I agree with everyone else. Once the antennas are working properly, it may go away. Chris If I remove the plastic inserts from the antenna mount, will that create a direct short when I am transmitting? I believe the splitter could be the problem also, like I said earlier if this my truck I would rip it all out and start from scratch. I did a little work ... swr @ 2.1. I just transmitted 9 miles. Whine still there ... might be louder. I am still wondering what is actually causing the whine i.e. alternator, fuel pump ....... maybe I need to look at the source of the whine rather than the ability to filter it out? |
In , "Randy" wrote:
snip Just so I am clear about one thing .... In all of these articles that I have been reading, when they talk about grounding the antenna, they are referring to a RF ground (ground plane) and not a physical ground? If for some reason the shield is not grounded would this be my problem? Close. Whine is RF interference from the engine electrical system (and sometimes other electrical devices like the fuel pump) and occurs on almost all vehicles. The difference is that an engine compartment which is fully enclosed by metal will shield the radio and coax from this noise (the noise can also pass through the electrical system, but that doesn't seem to be your problem). If you have a fiberglass hood, or if your coax passes through the engine compartment, the coax must be grounded at the radio end or it will pick up this noise just like an antenna. An RF ground is both an electrical ground -and- a physical ground. It is a low-impedance path for RF and is very dependent on the physical properties of the connection. Usually, a good RF ground is any point where electricity can easily take many different directions -- kinda like ****ing into a lake. Just about any point on the chassis will be a good RF ground. A single wire to the chassis is a better antenna than an RF ground. For example, if your radio is grounded with a wire longer than just a few inches it will allow RF voltage to develop on the radio chassis, and the radio effectively becomes part of your antenna system. That makes it very suseptible to engine noise and other types of RF interference that may be picked up by the coax shield (which is connected directly to your radio chassis) or passed through the electrical system to your power leads. So by RF grounding the radio (and therefore your coax) you are shunting all that RF interference to ground so the radio doesn't have to deal with it. Not having a good RF ground at the antenna can screw up your SWR, but that's about all. It's much more important to ground that radio! My boss will not care that this unit has a whine. I am not sure he would care whether it has a CB or not. I had to take the truck down to the shop last week to get the steer tires balanced, I had to pay for everything. He is not a bad guy ... just cheap! If it's a business expense it should be paid for by the business. The unit might not be grounded very good. It sits in an upper header console, just strapped in not bolted. I will ground the unit and purchase a noise filter then adjust my antennas. The upper header console is a terrible ground if your roof is fiberglass. I would recommend mounting it on the dash or the hump, close to the chassis. That will require rerouting the coax, but at this point that seems unavoidable. I tried reading as many articles as I could but they all were saying the same things and some of that I could not understand. I thank you for your time. I will let you know if the problem persist after these changes. Thanks again -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
In , Professor Bob wrote:
"Randy" wrote in : "Chris" wrote in message nk.net... You should be able to remove the plastic inserts where the antennas are mounted. You may also have a problem with the splitter that allows the stereo and TV to use the same antennas. Maybe you can use one antenna for the CB and the other for everything else. As for the whine, I agree with everyone else. Once the antennas are working properly, it may go away. Chris If I remove the plastic inserts from the antenna mount, will that create a direct short when I am transmitting? I believe the splitter could be the problem also, like I said earlier if this my truck I would rip it all out and start from scratch. I did a little work ... swr @ 2.1. I just transmitted 9 miles. Whine still there ... might be louder. I am still wondering what is actually causing the whine i.e. alternator, fuel pump ....... maybe I need to look at the source of the whine rather than the ability to filter it out? That would be your best bet, if your fuel pump comes on like most when you turn the key to on position without starting the truck, then you can tell if it is fuel pump or if vehicle started and the noise increases with engine rpm then it may be alternator or even the electronic ignition. Once you find out what it is then you can try and correct the problem otherwise you are shooting in the dark. Alternator whine and fuel pump noise can usually be correct by a capacitor and or choke, the igniton may need to be shielded to stop that. I believe he said that the whine follows the engine RPMs, so it's probably the alternator. Regardless, if you reduce or eliminate the source of the noise you are not fixing the problem, because the radio will still be suseptible to other sources of RFI such as the whine from other vehicles, power lines, industrial equipment, etc. It's as annoying as those pop-ups in your internet browser. Properly grounding your radio works like a good pop-up blocker. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Frank Gilliland" wrote in message ... In , "Randy" wrote: snip Just so I am clear about one thing .... In all of these articles that I have been reading, when they talk about grounding the antenna, they are referring to a RF ground (ground plane) and not a physical ground? If for some reason the shield is not grounded would this be my problem? Close. Whine is RF interference from the engine electrical system (and sometimes other electrical devices like the fuel pump) and occurs on almost all vehicles. The difference is that an engine compartment which is fully enclosed by metal will shield the radio and coax from this noise (the noise can also pass through the electrical system, but that doesn't seem to be your problem). If you have a fiberglass hood, or if your coax passes through the engine compartment, the coax must be grounded at the radio end or it will pick up this noise just like an antenna. An RF ground is both an electrical ground -and- a physical ground. It is a low-impedance path for RF and is very dependent on the physical properties of the connection. Usually, a good RF ground is any point where electricity can easily take many different directions -- kinda like ****ing into a lake. Just about any point on the chassis will be a good RF ground. A single wire to the chassis is a better antenna than an RF ground. For example, if your radio is grounded with a wire longer than just a few inches it will allow RF voltage to develop on the radio chassis, and the radio effectively becomes part of your antenna system. That makes it very suseptible to engine noise and other types of RF interference that may be picked up by the coax shield (which is connected directly to your radio chassis) or passed through the electrical system to your power leads. So by RF grounding the radio (and therefore your coax) you are shunting all that RF interference to ground so the radio doesn't have to deal with it. Not having a good RF ground at the antenna can screw up your SWR, but that's about all. It's much more important to ground that radio! My boss will not care that this unit has a whine. I am not sure he would care whether it has a CB or not. I had to take the truck down to the shop last week to get the steer tires balanced, I had to pay for everything. He is not a bad guy ... just cheap! If it's a business expense it should be paid for by the business. The unit might not be grounded very good. It sits in an upper header console, just strapped in not bolted. I will ground the unit and purchase a noise filter then adjust my antennas. The upper header console is a terrible ground if your roof is fiberglass. I would recommend mounting it on the dash or the hump, close to the chassis. That will require rerouting the coax, but at this point that seems unavoidable. I tried reading as many articles as I could but they all were saying the same things and some of that I could not understand. I thank you for your time. I will let you know if the problem persist after these changes. Thanks again -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- Actually the header is aluminum and part of the cab, not bolted or riveted. After working with it today I feel the alternator is the primary problem. Since I have no ignition and no whine with the key in the ON position (Fuel Pump), the alternator seems to be the culprit. I have been reading about installing a micro_farad capacitor between the alternator and ground in order to steady the voltage thus reducing the whine. I understand the theory but could use some feedback about the practical application. I feel this might be my least time consuming and least expensive solution. |
Frank Gilliland wrote:
It's as annoying as those pop-ups in your internet browser. Properly grounding your radio works like a good pop-up blocker. cool analogy. -- http://www.allpar.com/mopar.html |
In , "Randy" wrote:
snip Actually the header is aluminum and part of the cab, not bolted or riveted. Then you might get a fairly good ground right there. Bolt the bracket right to the aluminum and run the black power lead to one of the bracket bolts, cutting the wire as short as possible (no longer than six inches should be fine). After working with it today I feel the alternator is the primary problem. Since I have no ignition and no whine with the key in the ON position (Fuel Pump), the alternator seems to be the culprit. I have been reading about installing a micro_farad capacitor between the alternator and ground in order to steady the voltage thus reducing the whine. I understand the theory but could use some feedback about the practical application. I feel this might be my least time consuming and least expensive solution. You could try that, too. Find yourself a 'motor run' (NOT a 'motor start') capacitor of around 1 to 5 uF. They usually have tabs for terminals so you can use crimp connectors, and they can be mounted just about anywhere with a cable clamp. Mount it as close as possible to the alternator, or even right on the alternator if possible. Run one wire to the output and the other to ground, again keeping the wires as short as possible. The capacitor is not polarized so it doesn't matter which terminal goes to ground. But know that some regulators are messed up by putting a cap across the alternator. If you screw up your engine, don't blame me. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Steveo" wrote in message ... Frank Gilliland wrote: It's as annoying as those pop-ups in your internet browser. Properly grounding your radio works like a good pop-up blocker. cool analogy. He's fairly right on that analogy. Landshark -- The world is good-natured to people who are good natured. |
"Keith KC8TCQ" callsign @ qrz dot com wrote in message I've installed a few roof-mounts, but GM seems to be stingy when it comes to steel. If you don't reinforce the roof with some 0.064 or better it goes 'pong' whenever you go above 20 mph. My 75 Dodge I had a 102" whip with 4 inch spring mounted dead center of the the front rail of the bed right behind the cab, and to keep it from slapping into the back of the cab I put a tennis ball on the whip just below the roof of the cab. Worked like a charm with my old 148 GTL. A friend of mine tried using a mag mount antenna on the roof of his S-10, only problem is, he used a fiberglass whip which was a bit too heavy and not flexible enough, combined with a weak mag mount. End result, a Semi passed him, blew the antenna off the roof, it (the magnet) came smashing through the rear window and gave him a concussion. I too have used stud mounts and reinforced the body with washers and sheet steel. worked great. Dumbest installation I have ever seen, a guy bought an older S-10 4x4, it needed some body work but not much, he went out and bought a roll bar, had lights mounted on it, and mounted his antennas on it. It looked really sharp, Only one problem, he never got around to actually mounting the roll bars to his truck, one day he took off from a stop light in Toledo trying to act like Mr Bada$$ leaving Franklin Park Mall, his roll bars flew right out of the bed taking the lights and antenna with them. |
"Frank Gilliland" wrote in message ... In , "Randy" wrote: snip Actually the header is aluminum and part of the cab, not bolted or riveted. Then you might get a fairly good ground right there. Bolt the bracket right to the aluminum and run the black power lead to one of the bracket bolts, cutting the wire as short as possible (no longer than six inches should be fine). After working with it today I feel the alternator is the primary problem. Since I have no ignition and no whine with the key in the ON position (Fuel Pump), the alternator seems to be the culprit. I have been reading about installing a micro_farad capacitor between the alternator and ground in order to steady the voltage thus reducing the whine. I understand the theory but could use some feedback about the practical application. I feel this might be my least time consuming and least expensive solution. You could try that, too. Find yourself a 'motor run' (NOT a 'motor start') capacitor of around 1 to 5 uF. They usually have tabs for terminals so you can use crimp connectors, and they can be mounted just about anywhere with a cable clamp. Mount it as close as possible to the alternator, or even right on the alternator if possible. Run one wire to the output and the other to ground, again keeping the wires as short as possible. The capacitor is not polarized so it doesn't matter which terminal goes to ground. But know that some regulators are messed up by putting a cap across the alternator. If you screw up your engine, don't blame me. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- Well I have learned a tremendous amount about whine in a CB in the last week. I stopped by a shop today to purchase a capacitor that I was going to place on the alternator and the tech said he could fix the problem for twenty dollars. I watched him open the unit, desolder a capacitor and resolder a larger one in its place, he then shorted a couple of connections, probably tweaking the unit. I figure he was doing the same thing I was going to do but he did it inside the unit. I can just barely hear the whine ... well worth twenty dollars. I want to thank everyone for taking time to help me ... I did learn a lot and I might put it to use when I have more time. P.S. You all leave poor old George alone. If you would quit fueling the fire the fire would burn itself out. I do not know what started it but it is very detrimental to this group. |
|
In , "Randy"
wrote: snip Well I have learned a tremendous amount about whine in a CB in the last week. I stopped by a shop today to purchase a capacitor that I was going to place on the alternator and the tech said he could fix the problem for twenty dollars. I watched him open the unit, desolder a capacitor and resolder a larger one in its place, he then shorted a couple of connections, probably tweaking the unit. I figure he was doing the same thing I was going to do but he did it inside the unit. I can just barely hear the whine ... well worth twenty dollars. He didn't fix the problem, he just covered it up for a fee. It would cost you much less than twenty dollars to mount the radio properly, which would eliminate the whine (as well as other noises that the tech's 'fix' won't fix, as you will soon find out) -and- improve your antenna's SWR. I want to thank everyone for taking time to help me ... I did learn a lot and I might put it to use when I have more time. Better save these posts. You will need them in the future. You should also do a radio check to see if your audio is clipping -- the tech's 'tweak' may have been to bypass your limiter, which will cause your signal to splatter onto other channels. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Randy" wrote in message ... "Frank Gilliland" wrote in message ... In , "Randy" wrote: snip Actually the header is aluminum and part of the cab, not bolted or riveted. Then you might get a fairly good ground right there. Bolt the bracket right to the aluminum and run the black power lead to one of the bracket bolts, cutting the wire as short as possible (no longer than six inches should be fine). After working with it today I feel the alternator is the primary problem. Since I have no ignition and no whine with the key in the ON position (Fuel Pump), the alternator seems to be the culprit. I have been reading about installing a micro_farad capacitor between the alternator and ground in order to steady the voltage thus reducing the whine. I understand the theory but could use some feedback about the practical application. I feel this might be my least time consuming and least expensive solution. You could try that, too. Find yourself a 'motor run' (NOT a 'motor start') capacitor of around 1 to 5 uF. They usually have tabs for terminals so you can use crimp connectors, and they can be mounted just about anywhere with a cable clamp. Mount it as close as possible to the alternator, or even right on the alternator if possible. Run one wire to the output and the other to ground, again keeping the wires as short as possible. The capacitor is not polarized so it doesn't matter which terminal goes to ground. But know that some regulators are messed up by putting a cap across the alternator. If you screw up your engine, don't blame me. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- Well I have learned a tremendous amount about whine in a CB Not from Geo, but that's OK. He's useless, except for tax purposes. |
"Frank Gilliland" wrote in message ... In , "Randy" wrote: snip Well I have learned a tremendous amount about whine in a CB in the last week. I stopped by a shop today to purchase a capacitor that I was going to place on the alternator and the tech said he could fix the problem for twenty dollars. I watched him open the unit, desolder a capacitor and resolder a larger one in its place, he then shorted a couple of connections, probably tweaking the unit. I figure he was doing the same thing I was going to do but he did it inside the unit. I can just barely hear the whine .... well worth twenty dollars. He didn't fix the problem, he just covered it up for a fee. It would cost you much less than twenty dollars to mount the radio properly, which would eliminate the whine (as well as other noises that the tech's 'fix' won't fix, as you will soon find out) -and- improve your antenna's SWR. I want to thank everyone for taking time to help me ... I did learn a lot and I might put it to use when I have more time. Better save these posts. You will need them in the future. You should also do a radio check to see if your audio is clipping -- the tech's 'tweak' may have been to bypass your limiter, which will cause your signal to splatter onto other channels. Yes , I have already noticed alot of background noise where there was none before. I have already saved all of these post. When I have more time I will apply what I have learned. You will probably hear from me again :) |
"Keith Hosman" wrote:
"Keith KC8TCQ" callsign @ qrz dot com wrote in message I've installed a few roof-mounts, but GM seems to be stingy when it comes to steel. If you don't reinforce the roof with some 0.064 or better it goes 'pong' whenever you go above 20 mph. My 75 Dodge I had a 102" whip with 4 inch spring mounted dead center of the the front rail of the bed right behind the cab, and to keep it from slapping into the back of the cab I put a tennis ball on the whip just below the roof of the cab. Worked like a charm with my old 148 GTL. A friend of mine tried using a mag mount antenna on the roof of his S-10, only problem is, he used a fiberglass whip which was a bit too heavy and not flexible enough, combined with a weak mag mount. End result, a Semi passed him, blew the antenna off the roof, it (the magnet) came smashing through the rear window and gave him a concussion. I too have used stud mounts and reinforced the body with washers and sheet steel. worked great. Dumbest installation I have ever seen, a guy bought an older S-10 4x4, it needed some body work but not much, he went out and bought a roll bar, had lights mounted on it, and mounted his antennas on it. It looked really sharp, Only one problem, he never got around to actually mounting the roll bars to his truck, one day he took off from a stop light in Toledo trying to act like Mr Bada$$ leaving Franklin Park Mall, his roll bars flew right out of the bed taking the lights and antenna with them. DOH! The weekend warrior stirkes again..did he kick a hole in the muffler to make it sound race? :) -- And it's twice as hard on my stride When I take a day and let it ride. - Paul Cotton. |
What started it? N8wwm getting his clock cleaned after harassing cbers
for discussing various aspects of radio. His butties KC8LDO, N7VCF, WA3MOJ and N3CVJ all ran to defend him and his (felonious) law breaking ways while harassing others. They pushed too hard and sealed their own reputations as law breaking lids and have been angry ever since. They blame everyone else for their self-created misery and take no responsibility for their own actions. Hence their tired acts of trying to get off-topic personal information on those they are unable to debate intelligently. When the tables are turned, they begin to menstruate all over this group. They have always been able to dish it out but must be forced to swallow their own bitter prescription of what entertains their double-digit feebled minds. |
"Steveo" wrote in message ... "Keith Hosman" wrote: "Keith KC8TCQ" callsign @ qrz dot com wrote in message I've installed a few roof-mounts, but GM seems to be stingy when it comes to steel. If you don't reinforce the roof with some 0.064 or better it goes 'pong' whenever you go above 20 mph. My 75 Dodge I had a 102" whip with 4 inch spring mounted dead center of the the front rail of the bed right behind the cab, and to keep it from slapping into the back of the cab I put a tennis ball on the whip just below the roof of the cab. Worked like a charm with my old 148 GTL. A friend of mine tried using a mag mount antenna on the roof of his S-10, only problem is, he used a fiberglass whip which was a bit too heavy and not flexible enough, combined with a weak mag mount. End result, a Semi passed him, blew the antenna off the roof, it (the magnet) came smashing through the rear window and gave him a concussion. I too have used stud mounts and reinforced the body with washers and sheet steel. worked great. Dumbest installation I have ever seen, a guy bought an older S-10 4x4, it needed some body work but not much, he went out and bought a roll bar, had lights mounted on it, and mounted his antennas on it. It looked really sharp, Only one problem, he never got around to actually mounting the roll bars to his truck, one day he took off from a stop light in Toledo trying to act like Mr Bada$$ leaving Franklin Park Mall, his roll bars flew right out of the bed taking the lights and antenna with them. DOH! The weekend warrior stirkes again..did he kick a hole in the muffler to make it sound race? :) No idea, but you see alot of these fools around here, I saw a guy here in Napoleon who took a mint condition 70 Corvette, and turned it into a jacked up 4x4, modified the frame all to hell ect. This thing is literally so far off the ground he has a rope ladder rolled up inside the door, when he opens the door, he pulls the release, the rope ladder unrolls and he climbs up. He even painted it some god awful orange color. I'll try to take a picture of it next time he has it parked up at Family Video. |
"Keith Hosman" wrote:
"Steveo" wrote in message ... "Keith Hosman" wrote: "Keith KC8TCQ" callsign @ qrz dot com wrote in message I've installed a few roof-mounts, but GM seems to be stingy when it comes to steel. If you don't reinforce the roof with some 0.064 or better it goes 'pong' whenever you go above 20 mph. My 75 Dodge I had a 102" whip with 4 inch spring mounted dead center of the the front rail of the bed right behind the cab, and to keep it from slapping into the back of the cab I put a tennis ball on the whip just below the roof of the cab. Worked like a charm with my old 148 GTL. A friend of mine tried using a mag mount antenna on the roof of his S-10, only problem is, he used a fiberglass whip which was a bit too heavy and not flexible enough, combined with a weak mag mount. End result, a Semi passed him, blew the antenna off the roof, it (the magnet) came smashing through the rear window and gave him a concussion. I too have used stud mounts and reinforced the body with washers and sheet steel. worked great. Dumbest installation I have ever seen, a guy bought an older S-10 4x4, it needed some body work but not much, he went out and bought a roll bar, had lights mounted on it, and mounted his antennas on it. It looked really sharp, Only one problem, he never got around to actually mounting the roll bars to his truck, one day he took off from a stop light in Toledo trying to act like Mr Bada$$ leaving Franklin Park Mall, his roll bars flew right out of the bed taking the lights and antenna with them. DOH! The weekend warrior stirkes again..did he kick a hole in the muffler to make it sound race? :) No idea, but you see alot of these fools around here, I saw a guy here in Napoleon who took a mint condition 70 Corvette, and turned it into a jacked up 4x4, modified the frame all to hell ect. This thing is literally so far off the ground he has a rope ladder rolled up inside the door, when he opens the door, he pulls the release, the rope ladder unrolls and he climbs up. He even painted it some god awful orange color. I'll try to take a picture of it next time he has it parked up at Family Video. Sheesh, a west viginia vette modification if I've ever heard of one.. Did he put is the gun rack? g |
"Steveo" wrote in message ... "Keith Hosman" wrote: "Steveo" wrote in message ... "Keith Hosman" wrote: "Keith KC8TCQ" callsign @ qrz dot com wrote in message I've installed a few roof-mounts, but GM seems to be stingy when it comes to steel. If you don't reinforce the roof with some 0.064 or better it goes 'pong' whenever you go above 20 mph. My 75 Dodge I had a 102" whip with 4 inch spring mounted dead center of the the front rail of the bed right behind the cab, and to keep it from slapping into the back of the cab I put a tennis ball on the whip just below the roof of the cab. Worked like a charm with my old 148 GTL. A friend of mine tried using a mag mount antenna on the roof of his S-10, only problem is, he used a fiberglass whip which was a bit too heavy and not flexible enough, combined with a weak mag mount. End result, a Semi passed him, blew the antenna off the roof, it (the magnet) came smashing through the rear window and gave him a concussion. I too have used stud mounts and reinforced the body with washers and sheet steel. worked great. Dumbest installation I have ever seen, a guy bought an older S-10 4x4, it needed some body work but not much, he went out and bought a roll bar, had lights mounted on it, and mounted his antennas on it. It looked really sharp, Only one problem, he never got around to actually mounting the roll bars to his truck, one day he took off from a stop light in Toledo trying to act like Mr Bada$$ leaving Franklin Park Mall, his roll bars flew right out of the bed taking the lights and antenna with them. DOH! The weekend warrior stirkes again..did he kick a hole in the muffler to make it sound race? :) No idea, but you see alot of these fools around here, I saw a guy here in Napoleon who took a mint condition 70 Corvette, and turned it into a jacked up 4x4, modified the frame all to hell ect. This thing is literally so far off the ground he has a rope ladder rolled up inside the door, when he opens the door, he pulls the release, the rope ladder unrolls and he climbs up. He even painted it some god awful orange color. I'll try to take a picture of it next time he has it parked up at Family Video. Sheesh, a west viginia vette modification if I've ever heard of one.. Did he put is the gun rack? g No idea, but I'll suggest it to him when I see gim heheh |
Hello Frank
Can you recommend a book or two that will teach me about CB fundamentals, repairing and tweaking? I have an little electronic background and even own an oscilloscope. I think that if I learn the workings of a CB from the ground up it will be easier for me to troubleshoot them. The first book should be very basic so I can get the fundamentals down before diving off into the deep end. Thanks "Frank Gilliland" wrote in message ... In , "Randy" wrote: snip Well I have learned a tremendous amount about whine in a CB in the last week. I stopped by a shop today to purchase a capacitor that I was going to place on the alternator and the tech said he could fix the problem for twenty dollars. I watched him open the unit, desolder a capacitor and resolder a larger one in its place, he then shorted a couple of connections, probably tweaking the unit. I figure he was doing the same thing I was going to do but he did it inside the unit. I can just barely hear the whine .... well worth twenty dollars. He didn't fix the problem, he just covered it up for a fee. It would cost you much less than twenty dollars to mount the radio properly, which would eliminate the whine (as well as other noises that the tech's 'fix' won't fix, as you will soon find out) -and- improve your antenna's SWR. I want to thank everyone for taking time to help me ... I did learn a lot and I might put it to use when I have more time. Better save these posts. You will need them in the future. You should also do a radio check to see if your audio is clipping -- the tech's 'tweak' may have been to bypass your limiter, which will cause your signal to splatter onto other channels. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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