Link Systems

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RADIOGUY2002

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Link Systems

Is causing massive interfence to my radios for sure / repeater possibily.

Anything I can do to reduce this prolbem?
 

SAR923

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What's Link Systems? What freqency or frequencies are they operating on? Are you saying they are intefering with your scanner or a commercial two way radio system and repeater? If it's your scanner, then the ony answer is getting an appropriate filter. If you have a commercially licensed radio system, a call to the FCC may be in order.
 

RADIOGUY2002

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Correction linksys

Not sure what channel, but it the wireless rounter thats shooting harmonics across the radio waves. Yes, professional two way equipment. An it is quite apparant as I pulled the plug and it stoped.

Filter for a wireless router?
 

RADIOGUY2002

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Additional Update

So, after finding the route source of the prolbem I took apart some conections and found this out. I replace a cad5 cable out with a new one to the physical cable modem box. No more interfence, however when another feed line is appiled the rf noise comes back. I wondering if their needs to be a filiter on the fedline coming in to the box (cable) or if the cad5 cables were bad. I running the labtop off of wireless instead of a direct feed and no more noise. Any opionions to support my conclusions.


Also, why would this happen,

System A (10 watt repeater) at 30ft in the air would work better on portables lower to the ground (approx 5ft) then a 50 watt repeater (system B) with erp of 35 watts at 49 ft where the portables operate on ground level, would be worse.

System B and A both work equally as well at height above ground level at 15ft.
 

SAR923

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OK, so it sounds like your really have LINKSYS router that's giving you the problem. And the cable you're asking about is a category 5 Ethernet cable, correct? It's kind of important to get all these names right if you want decent information.

Cat 5 cable does go bad and some of it is very poorly shielded even when new. My experience is that Black Box shielded Cat 5 cable gives the best results in terms of noise shielding. It's not cheap but it will do the job. I have my scanner sitting right next to my router with no interference problems.

As to your repeater question, it could be a whole bunch of things. It could be that the coax going to the higher antenna is bad. It could be that you have two different antennas and one is better at putting out signals down toward the horizion instead of above the horizon. You don't give any details about the frequencies, types of antennas, coax, types of repeaters, portables, or how far away your portables are from the repeaters, it's impossible to give you much good advice.
 

RADIOGUY2002

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Sorry about that

OK, so it sounds like your really have LINKSYS router that's giving you the problem. And the cable you're asking about is a category 5 Ethernet cable, correct?

**(YES )**

Cat 5 cable does go bad and some of it is very poorly shielded even when new. My experience is that Black Box shielded Cat 5 cable gives the best results in terms of noise shielding. It's not cheap but it will do the job. I have my scanner sitting right next to my router with no interference problems.

**(will upgrade whenconnecting to the labtop direct to the linksys componet)**

As to your repeater question, it could be a whole bunch of things. It could be that the coax going to the higher antenna is bad.

**( Intersetingily enough I think that both antennas are at same height and are about 6 to 8 feet away frrom each other even though the licensece stiupates other wise or maybe the antena maybe for rx and the other for tx. Their new antennas and appear to be the same in diamter and height at approx 50feet.)**

You don't give any details about the frequencies

**VHF**
System A port tx 158 ranage and port rx on 155 ranage, Better system and older system, repeater is a motorola gr1225 rated at 10 watts and erp of 10 watts (license specs) Works better

System B port tx 159 ranage and port rx on 151 ranage, Newer system kenwood repeater I think at 50 watts tx and an erp of 35 watts

The portables used on the system are kenwood tk-2200's and motorola visars and ex600's. The portables are approx 1mile tio two miles away.

Area is mixed residental and industrial

---putting out signals down toward the horizion instead of above the horizon---
How do you determine what is better at doing it the right way in setup or specs?
 

jon_k

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Cat 5 cable does go bad and some of it is very poorly shielded even when new. My experience is that Black Box shielded Cat 5 cable gives the best results in terms of noise shielding. It's not cheap but it will do the job. I have my scanner sitting right next to my router with no interference problems.
99% of the CAT5/5E and 6 on the market is UTP (Unshielded Twisted Pair.) The only shielding you get is the plastic outer sheath.

They do make STP (Shielded Twisted Pair). It's made for industrial environments where specific threats are around.

E.g., wiretapping by inductance, RF leaking out of the twisted pair, RF leaking in to the twisted pair disrupting communications, etc.

I know that the bandwidth transmitted on twisted pair goes all the way up to 1ghz+. It's not surprising you may be getting RF interference.

Get some (expensive) shielded twisted pair cable and you should be set.
 

SAR923

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Ryan, exactly what kind of antennas do you have up there now? I'm really confused about your system. Are you saying a portable one mile away can't hit the repeater? Usually, a portable putting out 5 watts will work fine on simplex back to a base station with a good antenna 30 or 49 feet in the air for at least a mie even in bad RF environments. A repeater system should do much better. How does the base station get into the repeater? There must be something like a phone line or microwave. How far above AGL are these antennas located? Is this really a repeater system or just a base into an antenna? What I've read so far is both conficting and doesn't make sense.
 

RADIOGUY2002

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Ryan, exactly what kind of antennas do you have up there now?

-If I kew I woudl tell you. -

Are you saying a portable one mile away can't hit the repeater?

-Interminitily, has to be held a certain way or in a set direction, not the good old run and talk test. Drops it every time-

Usually, a portable putting out 5 watts will work fine on simplex back to a base station with a good antenna 30 or 49 feet in the air for at least a mie even in bad RF environments.

-Yes, I agree. However their is no base involved in this-

A repeater system should do much better.

-Toality agree, but that is not happening here-

How does the base station get into the repeater?

-No base station exists, all portables and a repeater-

There must be something like a phone line or microwave.

-Not built with rx sites or additional repeaters. Only one repeater at one fixed site-

How far above AGL are these antennas located?

-AMSL 202.2 Meters-
-18.2 Meters Hgt to tip-

Is this really a repeater system or just a base into an antenna?

-Repeater System FB2, the only thing I'm not sure of is the two antenas that are next to each other.-
Another words if it duplexed or not.-

Does any of these details help?

I don't understand why only certain spots work and others do not work, it not like it is directional. The antennas are onmi directional fiberglass sticks.
 

SAR923

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OK, let's try a test. I'm assuming you have simplex or talkaround on your portables. How far can you talk direct portable to protable on either side of the repeater location? That should give you some idea if the radios or the repeater is the problem. As far as the antennas, is this a full duplex repeater system? What is the input and output frequency? Normally, you only need one antenna for a repeater unless it's cross band so I'm not sure what the two antennas have to do with anything. Is this your system or are you trying to figure out a system you don't own or operate?
 

ka3jjz

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There is another possibility here. If the 2 antennas are too close together, it's quite likely that some sort of interaction is taking place creating dead spots. That might, at least partially, explain why the radios work 'a certain way or in a set direction'

??? 73 Mike
 

SAR923

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Maybe, Mike. In rereading his posts, it looks like there are two VHF repeaters with inputs and outputs near the same frequencies. I'm assuming the two repeaters are served by the two antennas. It's hard to tell what's really happening since RadioGuy doesn't even seem to know what the two antennas are or what they do.
 

RADIOGUY2002

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Additional, sorry I can not provide more details

Additional, sorry I can not provide more details. There is stuff I was not exposed to in regards to some of your questions.

((There is another possibility here. If the 2 antennas are too close together, it's quite likely that some sort of interaction is taking place creating dead spots. That might, at least partially, explain why the radios work 'a certain way or in a set direction. ))

This seems like its the case, its hit or miss an certain areas.

How far can you talk direct portable to protable on either side of the repeater location? About a mile roughily, and yes I now where your going with this question. I wonder that myself, that was step one. My personel repeater does not have this prolbem and operates near those bands.

As far as the antennas, is this a full duplex repeater system?

Thats one of the questions I can not answer, I'm wondering that myself. But, even if they used one antenna for rx and the other for tx why would this happen. Reference above, to close to each other???

What is the input and output frequency?

PORTABLE, The one with the prolbem
IN-159.7200
OUT-151.9550 **yes, thats right a business frequency as a repeater output**
 
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