Wilson 800mhz cellular amplifier for scanner

[TEKurtz]

I've searched around this site as well as others off and on for a while now trying to find any information with no avail. I had a thought a while back while trying to receive a somewhat local EDACS 800 system, and I wondered if this theory has been implemented or tested.
Wilson (among other brands) makes a cellular amplifier to be paired with a receiving and repeating antenna in the 800mhz and 1900mhz cell ranges, one made specifically for iDen 800mhz. My question is does anyone know if the normal cell amplifier/repeater or the iDEN version will work with an EDACS 800 system?
Just so there is no confusion, I'm not trying to extend the range of EDACS system to the neighborhood, I would like to pair my yagi antenna with the amp to repeat from an indoor antenna inside the house. Any thoughts?

 

[SkyPager]

You would be better off purchasing a wide-banded pre-amp for 600-1000 MHz. The Wilson Amps are a bit pricey for your application. In addition unless adjusted and installed correctly they will cause more problems than cure. Not necessarily for you, but for other users in the band. Unless you turn off the uplink signal you will be sending wide-banded noise out through the antenna. This signal will be in the uplink portion of the band and can block entire sectors for cell systems and PS repeater iputs. Also if you don't properly account for the isolation between the outside and inside antennas of the BDA it will oscillate; again causing problems for other users.
The Wilson units I have encountered do not have adjustments for uplink / downlink gain.

Additionally the use of a BDA (signal-booster) w/o permission from the cellular carrier is illegal. The end use of the BDA is irrelevant.

.http://www.rfsolutions.com/consumers.pdf

 

[kb0nly]

A cheap cable drop amp off ebay for $10-$20 would be far better, i use a PCT two port model thats 15db of gain from 54-1000Mhz and makes a great difference, not to mention splitting the antenna for two scanners.

 

[XTS3000]

I use a cable amp with adjustable gain. Its gain goes from -3 to +18 db and works surprizingly good. Got it at RadioShack many years ago.

 

[TEKurtz]

You would be better off purchasing a wide-banded pre-amp for 600-1000 MHz. The Wilson Amps are a bit pricey for your application. In addition unless adjusted and installed correctly they will cause more problems than cure. Not necessarily for you, but for other users in the band. Unless you turn off the uplink signal you will be sending wide-banded noise out through the antenna. This signal will be in the uplink portion of the band and can block entire sectors for cell systems and PS repeater iputs. Also if you don't properly account for the isolation between the outside and inside antennas of the BDA it will oscillate; again causing problems for other users.
The Wilson units I have encountered do not have adjustments for uplink / downlink gain.

Additionally the use of a BDA (signal-booster) w/o permission from the cellular carrier is illegal. The end use of the BDA is irrelevant.

Thanks for the info and your advice. I was told it wasn't too difficult to get permission from the carrier to use a repeater if I went that route. I should have also mentioned that the repeater would be not just for the EDACS, but for the AT&T cell phones in the house (as long as the repeater doesn't have to be iDEN), that being said I would not want to turn off the uplink.
I'll look into the wide-band amp as you said, and if a Wilson just won't work or I'm unable to get permission to use it, then I'll go that route.

A cheap cable drop amp off ebay for $10-$20 would be far better, i use a PCT two port model thats 15db of gain from 54-1000Mhz and makes a great difference, not to mention splitting the antenna for two scanners.

Thank you as well for your response. Currently I use a high end bi-directional 40-1000Mhz 20db amp, just as you mentioned in your post. It's not cutting it for me, that's why I'm looking for a more powerful amp.

 

[kb0nly]

If your already using a 20db gain preamp and its not working i think you need to take your system and give it a long hard look.

I would make improvements to feedline and antenna then, because if your already running 20db of gain now any more amplification is just going to bring up the noise floor and make things worse!

I would consider a yagi pointed at the system your trying to monitor.

As for the cellular, talk to your provider, get a BDA from them or at least permission from them and go from there. Your going to have to treat this as two seperate systems, your not going to be able to combine them, which is what it sounds like your trying to do.

If your provider has the option get a network extender. I'm going to be buying one myself for Verizon, their data coverage sucks where i live, voice is ok, but texting and multimedia messages routinely fail.

 

[TEKurtz]

If your already using a 20db gain preamp and its not working i think you need to take your system and give it a long hard look.

I would make improvements to feedline and antenna then, because if your already running 20db of gain now any more amplification is just going to bring up the noise floor and make things worse!

I would consider a yagi pointed at the system your trying to monitor.

As for the cellular, talk to your provider, get a BDA from them or at least permission from them and go from there. Your going to have to treat this as two seperate systems, your not going to be able to combine them, which is what it sounds like your trying to do.

If your provider has the option get a network extender. I'm going to be buying one myself for Verizon, their data coverage sucks where i live, voice is ok, but texting and multimedia messages routinely fail.

I currently use a 800mhz yagi antenna, which replaced my parabolic. It's about 75 feet of RG6. The thing of it is, .5 miles down the road the EDACS system comes in clear with an omni directional 800mhz and no preamp. The trees by my house cut the signal out just enough so that the Control Channel cuts in and out. When I view the feed with ProScan software I'm just on the brink off acceptable db level. I've gone over the entire thing a few times looking for anything that can cause attenuation. All other conventional and trunked systems come in fine over a decent radius considering that I'm in a huge valley. I'm confident with an extra 20db it will do the trick.

 

[kb0nly]

What is the yagi rated for gain?

With 75ft of RG6 at 800Mhz your loosing 4-6db depending on the quality of the coax, which is significant. I'm assuming your amp is at the scanner?

I would try one of two things...

1. New feedline, LMR400 or better, 1/2" hardline, you name it. More is better at that run length.

2. Mast mount preamp instead of an inside amp. Would be far more effective to amplify the available signal before the feedline loss.

If you have 20db of gain now and want another 20db, your only going to amplify the noise as there isn't enough signal to begin with, trust me on this been there many times. Not to mention your going to have a hard time finding a preamp that will give you 40db of overall gain without a big increase in noise.

I understand your frustration.. But for the cost of a better amp you could put up better coax and even move to a mast mount wideband preamp instead. There is many available on the market.

 

[TEKurtz]

When I was troubleshooting the first time I tested the loss of the RG6/U and it was a 4.5db difference at 850Mhz without the use of the amp, using a 6" jumper at the antenna. That to me doesn't seem like enough loss to justify upgrading the cable. My amp is waterproof but I have it installed inside at about 20' from the antenna. I tried a trap at one point but it didn't help, I removed it because I wasn't able to pickup other systems on different bands, obviously.
I may try a different drop amp, or even try doubling it up just to see what the outcome would be. Do you have any recommendations on a wide-band amp that you mentioned?

 

[kb0nly]

Hmm, you are in a difficult pickle then. So if understand this right, antenna to amp is 20ft and then another 55ft roughly to scanner right? That's not bad then since you are making up for a majority of the loss with the amp fairly close to the antenna.

I have been using PCT branded amps off ebay with great results. Do a search for PCT Amp, or PCT Drop Amp on eBay and you will see many to choose from. They are a wideband amp, 54-1000Mhz, and an average of about 15db of gain according to the manufacturer.

There is other drop amps available on ebay as well that you might want to search through as well. I would try another amp seperately and just see if that makes a difference compared to the amp your using now, couldnt hurt. Most of the PCT models have a combined output/dc input port on them so that you can run power up the coax with the power injector located down in the shack. But they also have a seperate power input as well. However thats for 2 port or more, if you bought a single port then you would need to provide power at the amp location, but it sounds like you already have that for the current amp.

If you use one of these amps with multiple outputs and only use one output then put 75 ohm terminators on the unused ports.

 

[TEKurtz]

Yes, it's a very aggravating situation. Your correct with the distance from antenna to amp to receiver.
I've looked on ebay for quite some time at different cable drop amps similar to mine trying to find one that may be better as far as S/N ratio and db rating. I think you make a good point, it's crossed my mind that my amp could have defected over time, I know it works as it should on some bands but that doesn't necessarily mean that it's hasn't been damaged at some point (lightning, power surge). I would hate to waste the $ on a new amp if it doesn't make a difference, even if it is only $20-$40. I don't think I would pick up a cheaper one however for the simple reason the cheaper construction could cause more problems. The current amp I use has a separate 12v input over coax, I don't mind it because I can make a jumper any length I need. I'm assuming that the combined 12v supply with the output would be okay since radio freq. travels on the outside of the conductor, but if I can I would like to avoid amps like that. Also I would want a single output amp again, I wouldn't want the 3.5db loss per leg, and I can always add a GHZ splitter for a 2nd receiver if need be.
Thanks for your thoughts and suggestions, it has helped. If anything crosses your mind at some point feel free to bounce it off me, I'm open to ideas.

 

[zz0468]

I would strongly urge you to avoid a Wilson cellular amp at all costs. They're poorly designed, poorly shielded, and quite likely illegal to operate. I doubt you could get permission from any cellular carrier to install one, and even if you could, use with the EDACS system wouldn't be covered unless the licensee of the EDACS system authorized it. Ain't gonna happen.

Consider this an educated opinion. Being in the public safety radio industry, I have personally gone on direction-finding expeditions to track down the noises causing service outages to public safety systems and found Wilson cellular amplifiers to be the culprits. The devices I've found were so poorly shielded that they oscillated even when the subscriber side antenna port was terminated in a dummy load. I was NOT impressed with the quality of the damned things.

 

[TEKurtz]

I would strongly urge you to avoid a Wilson cellular amp at all costs. They're poorly designed, poorly shielded, and quite likely illegal to operate. I doubt you could get permission from any cellular carrier to install one, and even if you could, use with the EDACS system wouldn't be covered unless the licensee of the EDACS system authorized it. Ain't gonna happen.

Consider this an educated opinion. Being in the public safety radio industry, I have personally gone on direction-finding expeditions to track down the noises causing service outages to public safety systems and found Wilson cellular amplifiers to be the culprits. The devices I've found were so poorly shielded that they oscillated even when the subscriber side antenna port was terminated in a dummy load. I was NOT impressed with the quality of the damned things.

THANK YOU!
I needed to hear something like that before I went and dropped a couple hundred bucks on one. Now the only other advice from you, with your knowledge on public safety radio systems, that I would be greatly appreciated is; how the hell do I pick up this not so distant EDACS system, what amp and or antenna combo would you recommend? Thanks again

 

[rfradioconsult]

What does your Line of Sight (LOS) look like between your location and the site you are trying to monitor? At 800 MHz there may not be a inexpensive solution. There are sites on the web where you can enter the location coordinates and generate a path profile.

 

[kb0nly]

I was gonna ask about LOS also...

He did mention trees, and going down the block its better. Could a change in height or antenna location help? Maybe not possible but have to ask without seeing it!

 

[kb0nly]

I would strongly urge you to avoid a Wilson cellular amp at all costs. They're poorly designed, poorly shielded, and quite likely illegal to operate. I doubt you could get permission from any cellular carrier to install one, and even if you could, use with the EDACS system wouldn't be covered unless the licensee of the EDACS system authorized it. Ain't gonna happen.

Consider this an educated opinion. Being in the public safety radio industry, I have personally gone on direction-finding expeditions to track down the noises causing service outages to public safety systems and found Wilson cellular amplifiers to be the culprits. The devices I've found were so poorly shielded that they oscillated even when the subscriber side antenna port was terminated in a dummy load. I was NOT impressed with the quality of the damned things.

Actually there is a lot of Wilson amps in use around here, one that i know of in a fire station, without it no signal to cellphones in building. They were all approved and installed through channels so they can't be that bad.

I have one as well, talked to Verizon about getting a network extender, yeah they want $250 for it and it uses my internet to provide the service they should be. I don't think so. If they gave me the extender free as an appology for horrible service i would take it. Until then the Wilson amp gets me a nearby tower that has EVDO while mobile, while at home i have no data service, but so-so voice coverage. When i mentioned the amp they of course wanted to sell me a kit for my vehicle, i asked and they wanted $400+ for it. I said no i will get my own, the gal just said ok i hope it works out for you is there anything else i can help you with. They didnt seem to concerned.

 

[zz0468]

...Now the only other advice from you, with your knowledge on public safety radio systems, that I would be greatly appreciated is; how the hell do I pick up this not so distant EDACS system, what amp and or antenna combo would you recommend? Thanks again

Advanced Receiver Research makes some pretty decent low noise preamplifiers. Angle Linear makes even better ones. But even the best preamp won't create signal where there is none. Start looking here:

Advanced Receiver Research

Try your scanner on a good outside antenna, maybe a yagi pointed toward the system you want to hear. Use the best coax that you can afford. LMR400 is decent for that application. Hook it up direct to the receiver, not via some sort of device like the Wilson amps. See what the reception is like. If it's readable but noisy that way, a good preamp will likely help.

If you hear nothing, there's a good possibility that there's nothing to be heard. 800 MHz systems are frequently carefully designed to NOT cover outside their intended service areas.

The main specification to look for in a preamp is noise figure. A 1 db noise figure is pretty good. A 2 db noise figure is worse, so the lower the number, the better. Scanners have a noise figure from about 4-6 db. Many cable drop amps have noise figures in the range of 8 db so, while they'll make strong signals stronger, they'll make really weak signals just go away. Getting a preamp to actually help is a science, and just throwing gain at it is not the solution.

 

[TEKurtz]

I have all the line of sight info saved on my desktop, unfourtunately I just have my iPhone right now. When I get back I'll post my findings. However I remember not being sure which antenna sight was the one I needed. There are 4 listed with the FCC for the city of Hartford. One of them is on a mountain very close to my house, the only thing is the city is on the opposite side of mountain as my house, and if the antenna is oriented towards the city and not omnidirectional then that would explain the issues I'm having.
As far as antenna height, I've tried going up to about 35 ft. My best results were when I was below the tree line pointing the parabolic dish towards the clearing in the direction of the city. At best I get a few of the 16 freq clearly only to have the others mostly static.
Also I found my amp to not be boosting the db on anything higher than 400Mhz any longer. So it's time to replace it.

 

[TEKurtz]

Advanced Receiver Research makes some pretty decent low noise preamplifiers. Angle Linear makes even better ones. But even the best preamp won't create signal where there is none. Start looking here:

Advanced Receiver Research

Try your scanner on a good outside antenna, maybe a yagi pointed toward the system you want to hear. Use the best coax that you can afford. LMR400 is decent for that application. Hook it up direct to the receiver, not via some sort of device like the Wilson amps. See what the reception is like. If it's readable but noisy that way, a good preamp will likely help.

If you hear nothing, there's a good possibility that there's nothing to be heard. 800 MHz systems are frequently carefully designed to NOT cover outside their intended service areas.

The main specification to look for in a preamp is noise figure. A 1 db noise figure is pretty good. A 2 db noise figure is worse, so the lower the number, the better. Scanners have a noise figure from about 4-6 db. Many cable drop amps have noise figures in the range of 8 db so, while they'll make strong signals stronger, they'll make really weak signals just go away. Getting a preamp to actually help is a science, and just throwing gain at it is not the solution.

Thanks again for the input. I've seen the ARR amps online, I wasn't sure of how good they were, I'll look more into them now.
I've done all the proper testing without any amplification, a 6" jumper from the antenna to the receiver and directed the dish to the best signal. As I mentioned in the above post only a few of the channels come in well (above 120db) the rest are below 90db, there is no in between.

 

[TEKurtz]

Looking again at the FCC info, the 4th tower has no call sign. There are 3 and within the city itself on the opposite side of the mountain about 10-15 miles away. The tallest tower is only about 375 feet agl, and the polarization is vertical.