p25 800mhz antenna and setup HELP

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acecducec

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Im in the heart of carrollton ga i want to relay city pd and county pd and fire i have a tx-1 on the way.
Got 100 ft run of rg6 to bnc on radio hd tv antenna (See pic) on top of house pointed at nearest p25 tower 5 miles away... feeding signal....no splitters just barrel connectors and grounding wires. 2.5 mm headphone from scanner to pc running win7.

Questions
1. TRX-1 will fix missing conversation issue? (ie getting mostly dispatch feed)
2. Will omnidirectional work better picking up cars near me
3. On 100 ft run would the heavy coax improve reception?
4. Should i put a booster off antenna in between the radio
5. Is there tweeks for the radio software that will improve conversation fluency
6. I have a hum on the broadcastify feed. How to clear it up?
7. Can you call me i get more done with 5 min conversation than 1 week of email?
8. Yaggi or UHF/VHF? (Pic attached)
9. The TRX-1 on yagi. Hdtv. Or a dimond spider antenna?
10. Do you love your life?


Thanks for your help


Jason


Updates soon

Pics to come got old school antenna and yag
 

mmckenna

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Im in the heart of carrollton ga i want to relay city pd and county pd and fire i have a tx-1 on the way.
Got 100 ft run of rg6 to bnc on radio hd tv antenna (See pic) on top of house pointed at nearest p25 tower 5 miles away... feeding signal....no splitters just barrel connectors and grounding wires. 2.5 mm headphone from scanner to pc running win7.

Questions
1. TRX-1 will fix missing conversation issue? (ie getting mostly dispatch feed)
Not sure what you are asking here. Are you asking about error correction on the signal?
Ideally, if you have a good strong signal and everything is working correctly, this shouldn't be an issue.

2. Will omnidirectional work better picking up cars near me
Yes. However, if you are listening to a repeated system, all you need to do is listen to the repeater output and you should hear everything. If it's a simplex system (no repeater) then an omni directional antenna would be a better choice.

3. On 100 ft run would the heavy coax improve reception?
Depends. There's a thing called a "loss budget". Thats where you take the level of the received signal, multiply by antenna gain, subtract coaxial cable losses, connector losses, etc. and what you have left over when it reaches the radio should be more than the minimum sensitivity of the radio. If its more, then you are good. If it's less, you need to change one or more of the numbers.
RG-6 should work pretty well in most cases. If you have the budget and you are listening to a 700MHz or 800MHz system, 100 feet is a long cable run and may benefit from higher grade cable. LMR-600, 1/2" heliax, 7/8" Heliax, the exact type depends on the entire system.

4. Should i put a booster off antenna in between the radio
See above about loss budgets. If you are in a weak signal area, you can improve coverage a bit by putting an RF preamplifier at the antenna. This will boost the received signal and send more of it down the coaxial cable. This can be good in some cases, bad in others. Good can be pulling in a weak signal, hearing something you normally wouldn't, etc. Bad would be increasing noise floor, overloading receiver from nearby cell towers, broadcast, etc.
The old saying "You can't get something for free" applies here. Adding a preamplifier isn't "free" signal. It increases all signals in its passband, even stuff you may not want.

5. Is there tweeks for the radio software that will improve conversation fluency
I don't know the answer to that question in relation to a consumer scanner. I do know that on the commercial stuff I work on, there are a lot of settings that can impact audio quality. Someone who owns one of these scanners could tell you for sure. Might be worth starting an entirely new thread with just one questions. It makes it easier for people to answer ;)

6. I have a hum on the broadcastify feed. How to clear it up?
Probably a ground loop. One thing to try is lifting the ground on one end of the audio cable. There are various ways to fix this, I'll leave the details to those who have specifically solved this issue.

7. Can you call me i get more done with 5 min conversation than 1 week of email?
No, me and phones don't get along.

8. Yaggi or UHF/VHF? (Pic attached)
No picture, so I can't assist.

9. The TRX-1 on yagi. Hdtv. Or a dimond spider antenna?
Not sure what you are asking. If you are asking which one will work better, it really depends on what you are trying to listen to. If you are trying to listen to a single system, the ideal solution is to use a Yagi antenna pointed at the radio site. HDTV antennas will usually work pretty well as the frequencies they are designed for are pretty close. Diamond Spiders are an option, but there are better choices _depending_on_what_you_ are_doing.

10. Do you love your life?
Absolutely, best one I've had so far. Wouldn't trade it for anything.

Thanks for your help


Jason


Updates soon

Pics to come got old school antenna and yag
Pictures would help. You can use something like Photobucket.com. Upload your pictures and then you can post a img file.


As for not getting any answers, sometimes it works better if you keep it to just a few questions. Being specific in each post often gets you better results.
 

teufler

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the HD TV will work, not optimum but stronger than an omni directional assuming its pointed in the right direction. Clarity of you signal, you have simulcasts problems. the beam woulds help isolate one tower, probably the Oak Mill Rd tower. That may be the tower you say is only 5 miles away. If the beam heading extends to Coweta Cty, you would do better with a small vertical antenna, that would give local coverage and not be good enough to extend to the next county. 100 feet of coax seems alittle long for the height of your antenna. The system that is in Carroll cty, the 800 mhz system, no need to program cars because its all on repeaters so just he output frequency. Now the normal vhf system, cars and bases, thats a different deal. The choice of antennas, you don't have a good antenna, though I have a frioend down in Arkansas that uses a tv antenna like the top antenna, gets range of 100-125 miles
 

mmckenna

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So, the lower Yagi antenna is pretty high frequency, well above 800MHz. Is that the one you are talking about using? Or is it the TV antenna?


The lower yagi isn't going to work well for what you want to do. The TV antenna will, but since it's horizontally polarized and the signals you want to listen to are vertically polarized, you are introducing some signal loss.
You -could- turn the antenna 90º on the long axis, but that's probably going to result in your neighbors asking a lot of questions and poor TV reception (if you are still using for that). The benefit is that the antenna will work from VHF Low band VHF high, and UHF pretty well.
Still, if you are trying to just listen in on a single 800MHz system, a dedicated antenna designed for the band will outperform.
 

acecducec

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Antenna

Ok thanks for the reply
could you send me a link to a good antenna for 800mhz
i have looked around on the internet and on ebay and not sure to get a pole antenna or a directional
Im not using the antenna for tv have charter for tv and internet
I read of people using the Yagi antenna but i doesnt pick up much so i have the broadcast on the tv antenna right now and just got a tx-1 in today.
 

mmckenna

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There's some good low end 800MHz Yagi's on Amazon. Not super durable, but fine for hobby use. Wilson, the company that makes cell phone boosters sells a few.

If you want a higher end model, you can look here:
https://www.tessco.com/search?category=Outdoor Base Station Antennas|SMR Antennas|SMR Yagis

If you are putting all this work into the antenna, you might be well served by looking at the coaxial cable too.
Figuring out exactly how much cable you need to keep the run sort will benefit reception. Also, stepping up to a higher grade cable, like LMR-600 might be useful, but you might be able to do with a smaller cable. Either way, get the connectors to match the antenna to keep things easy, simple and reliable.
 

acecducec

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New 800mhz antenna

Well i installed the new 800mhz antenna and could not pickup much at all so i reinstalled my hdtv antenna to get the feed back up. I measured the cable length and it is 45ft.
In the 45 foot on the Yagi had heavy coax for 3ft then converted to rg6 for the other 42 ft with 2 barrel connectors 1 for ground and 2nd for cable splice then BNC to the radio.
I only use the antenna for the radio.

Would i need an hdtv booster to get the signal stronger to the radio? on the new Yagi?

800 MHz Yagi antenna Telewave ANT850Y10-WR 824-896 MHz Tested is the antenna in the pic
 

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mmckenna

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Sounds more like a cable/adapter issue.

The yagi should have considerably more gain at the frequencies you are using. In other words, it should be working better than the HDTV antenna.

An amplifier might work if everything else is OK, but you'd need to confirm that first.
 

cpetraglia

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There are two things I see. First the cabling is an issue. The second looks like the antenna may have a down tilt, but that could be the picture. I have always had better results with a slight up tilt (4-5 degrees) at most. That antenna should out perform the TV antenna for 800Mhz by a bunch. If affordable, I would use LMR400 from antenna to radio with only one short light duty cable for the radio connection. You can ground the shielding anywhere along the run without additional connectors. If you must use connectors, use only N-Type connectors. At 5 miles if your still not getting signal, There is likely something else going on. I don't believe a pre-amp would make it any better. I have to assume you have plotted out the proper aiming toward the tower.
 

abnrto

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I just tryed to be about 5 miles away with no ant. on a mobile radio and still picks up the system. Now this is an APX radio and not a scanner. I do know some of the newer scanners I've seen doesnt work too good on the Carroll (800) channels but works good on the Coweta (700) channels.
 

acecducec

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I think i got it i took out all the conventional channels and just left the 800 it think it scanning all the channels and i just want the 800 ones
Its coming through pretty clear.
Now just got to get my 350.00 yagi to hook up . ebayed it for 50.00
 

acecducec

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There are two things I see. First the cabling is an issue. The second looks like the antenna may have a down tilt, but that could be the picture. I have always had better results with a slight up tilt (4-5 degrees) at most. That antenna should out perform the TV antenna for 800Mhz by a bunch. If affordable, I would use LMR400 from antenna to radio with only one short light duty cable for the radio connection. You can ground the shielding anywhere along the run without additional connectors. If you must use connectors, use only N-Type connectors. At 5 miles if your still not getting signal, There is likely something else going on. I don't believe a pre-amp would make it any better. I have to assume you have plotted out the proper aiming toward the tower.
Found this guy on Ebay has some great prices going to order LMR 400 50ft

fiberom4

Thanks for the advice
 

mmckenna

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Just make sure it's real LMR-400, not "LMR-400 equivalent" or some other tricky wording.
The true LMR-400 only comes from Times Microwave. CNT-400 is a good version made by Comm Scope.
There are a few Chinese knock-offs out there. Be careful of those. While they may have similar dimensions, they are not the same.
For a 50 foot run, you likely won't save much by not getting the real thing.
 

acecducec

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Just make sure it's real LMR-400, not "LMR-400 equivalent" or some other tricky wording.
The true LMR-400 only comes from Times Microwave. CNT-400 is a good version made by Comm Scope.
There are a few Chinese knock-offs out there. Be careful of those. While they may have similar dimensions, they are not the same.
For a 50 foot run, you likely won't save much by not getting the real thing.
here is what i am ordering

US MADE LMR-400 50 FT N male to N male COAX CABLE Antenna (CNT-400) | eBay

Says MADE IN USA on the cable HOORAH
 

mmckenna

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Looks good to me.
$50.00 isn't a bad price, and $13.00 for shipping isn't either.

As long as they are quality N connectors that have been properly installed, that should be a good setup.

Just make 100% sure you waterproof your outdoor connections well. A layer of electrical tape isn't enough. Ideally you want a layer of electrical tape laid down covering the entire connector and past it a few inches. Follow that with a layer of coaxial cable sealing tape. This is a moldable mastic type sheet. Cover all that with a second layer of electrical tape covering everything and extending a few inches past the sealing tape.
 

acecducec

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Over Kill

Ok the other feed in my area went down so now im the only one broadcasting and have a usual listener base of 10-20 listening and when bad weather 40+
I could not get the feed just right so i tested with my HDTV antenna vs. the Ducky antenna, and believe it or not the Ducky antenna out preforms the HDTV.

My question is if the Ducky antenna is picking up better i can mount one on the side of the house and run coax to the inside about 40ft. using BNC connectors?

I still have the LMR cable coming. and have the Yagi mounted.

I am wondering if the tower right beside my house is rebroadcasting the P25 System?

Metropolitan Communications, Inc.
103 Commercial Ave.
Carrollton, GA 30117

????
 
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