Atic antenna...

[justrfb]

Hello All.
I thankfully have my new to me scanner running properly now... I am interested to know the best antenna I could get to put up in my attic and run the wire down to my scanner. Please let me know... Thanks.

Sincerely,
Rich

 

[popnokick]

The usual questions and answers (from you) will apply to be able to get you the best advice....
What agencies (frequencies / services e.g. aircraft) do you listen to / want to hear the most?
Are there some that you don't listen to at all?
How much space is in your attic (how high)?
Do you have an upper limit on your budget?
Correct to assume that you have a BCT15?

 

[cellphone]

Radio Shack 20-176 (if they are still around) is one of my favorites. It is small and for the price it is a great choice for VHF and UHF. Antennas on the scanner often do better on 700-800 MHz since you lose so signal much in the feed line. If your primary interest is distant 700-800mhz, you would be best with a directional antenna and low loss quality cable.

 

[ofd8001]

Rooftop Wide-Band Antennas for Police Scanner Radios | ScannerMaster.com

I've used the ST2, ST3 and ST4 antennas with good results. Probably the better of them is the ST4.

The ST2 might be a little tall for an attic however.

 

[Robertolson]

Plus 2 on the ST4 as it has the smaller Coax cable which makes it much easier to route it down to your Scanner.

 

[AZIntrepid]

Does an antenna in the attic work as well as mounting it on top of the roof?

 

[dmg1969]

I have 3 antennas up in my attic. A mobile Hustler MOR-B, a homemade OCFD and an Antennacraft ST-3. When running only one scanner, I usually use the ST-3 because it is the best of the 3 on UHF. Just make sure you get an antenna meant for the frequency range you want to listen to...or a wideband antenna.

 

[lep]

Does an antenna in the attic work as well as mounting it on top of the roof?

No.

 

[justrfb]

Hello All.
Thank you for your help... I am just looking for an antenna better than the stock one I stick on the back of my scanner now... If that is a "wide band", then that is what I am looking for... Is the St-4 a "wide band" antenna? Thank you again...

Sincerely,
Rich

 

[popnokick]

[Providing a limited answer here because the questions asked in the first reply in this thread have gone unanswered....]
Discone antennas are by design wide frequency coverage ("wide band"). The ST-4 is a discone and therefore a "wide band" antenna. With scanner antennas there are three major considerations... the physics of RF and antenna design pretty much dictate that you can't have all three of these at the same time:
- Wide frequency coverage
- High gain
- Omnidirectional operation
Even further limitations start to apply when you are constrained by an installation in a limited space (e.g. an attic).
A discone sacrifices gain (it has none) for wide frequency coverage.

 

[justrfb]

Hi popnokick...
Sorry... I will try to answer your questions... Please be patient with me... I feel like a very small fish in a very big lake in this hobby now!!

I like to listen to and want to hear your typical civil service agencies... Police, fire, emergency and department of public works for towns in morris/ sussex and warren New Jersey counties. I would like to listen to anything... If I can receive it, I will listen to it...

There is nothing I wouldn't listen to unless I couldn't...

I would guess about 4' - 5' of room in my attic...

About $50.00 or so for the antenna and another $25.00 or so for needed hardware.

And correct, I have a firware updated (for rebanding) Uniden BCT15 scanner.

Thanks for your help.

Sincerely,
Rich

 

[jonsmth]

Attic Antenna

Rich,

I built a dipole antenna using two lengths of 3/4" Copper pipe and a CPVC-T to join them together. The antenna is mounted in a 4' attic space I have on the front of my house. I am lucky as my house is on the side of a mountain and at about 1700' above sea level facing a valley where I desire to pick up most of my communications. The exception is the trunking system in our area which is about 30 degrees to the east of due north. I spent about 8 to 10 bucks on the pipe, a couple of dollars for the CPVC-T and about 5 bucks for a R/S 4:1 balun (300 ohm to 75 ohm transformer). This antenna is mounted vertically since most Public Service antennas are mounted vertically is exceptional. I used a wavelength calculator I found online to calculate the length of the pipe for a 1/2 Wave length antenna. I picked 154.000 MHz as a resonant frequency. It picks up the VHF band exceptionally well and is just as good on the 800 MHz trunking band. I have picked up strong signals on VHF from as far as 75 miles away with this antenna. It also picks up Air Band and Railroad signals very well. For about 15 bucks I have a great Omni-directional antenna. I also built a separate antenna for the FM Broadcast Radio Band. Mounted this antenna horizontally in the same attic space. Using a Vintage Kenwood KT-615 Tuner it pulls in stations in the 60 mile plus range with ease.

 

[wa8pyr]

Rooftop Wide-Band Antennas for Police Scanner Radios | ScannerMaster.com

I've used the ST2, ST3 and ST4 antennas with good results. Probably the better of them is the ST4.

The ST2 might be a little tall for an attic however.

I've got two ST2-equivalent models in the attic fed to the scanners (in the home office on the second floor) with good quality RG6. Works like a charm on all bands, although low band is not quite as good; however, since there is very little low band use left around me, it's not an issue.

 

[justrfb]

Hello All and thank you.

I am excited to say I am going to build my own dipole (for my attic) as jonsmth and others have suggested... I might even have some of the stuff at home already... Thank you!

Sincerely,
Rich

 

[jim202]

Running the coax cable from the attic down to the room where the scanner is could be a chore.

I have done this in several houses I have had over the years. On the up side, they were all single story homes. I was able to find an inside wall where I wanted to use the scanner. Drill a 3/4 inch hole in the header up in the attic on the wall where the scanner would be.

Found an outlet on the wall where I wanted to use the scanner and used that as a location to use for finding the power cable feed in the attic. Figure out if the next stud was to the left or right of the outlet with a stud finder. This then allowed you to figure out which side of the power cable to drill the hole (3/4 inch) in the ceiling header.

Once you have the hole in the header, you can use a snake to push down from the top and listen for it in the wall. I use a low voltage outlet wall insert with the flip down fingers at the top and bottom. Cut a hole in the sheet rock just large enough for the low voltage insert plate to fit. Look for the snake. Might have to take a metal coat hanger to push through the opening to locate the snake.

It helps if there are 2 people working on this. Pull the snake through the opening. Tie on a string or wire and tape it to the snake. Pull it up to the attic. Tale and tie the coax to the string or wire up in the attic and slowly pull the coax back down to the room. Make sure you have enough coax to make it to the scanner location before you cut the length of the coax.

You can use a blank plate to cover the hole in the wall. Drill a hole in it to feed the RG58/U coax through. Use a small bit for the first hole. Then gradually increase the drill size until you get the correct size hole. The short run from the antenna to the scanner in this case should not effect the ability to hear weak signals. Put the coax connector on after you get the cable through the plate.

Some words of caution on trying to snake cables in the wall. On newer homes, you will find a fire stop about half way up the walls. This is a 2x4 run horizontal inside the walls between the vertical studs. On older homes, this fire stop probably won't be there and you will be able to go top to bottom of the wall with no problems. Just what year these fire stops were required will depend on the local building codes.

Work carefully and enjoy the efforts of your work once the antenna coax cable is run from the attic to your scanner.

 

[popnokick]

Rich- A couple of more tips:
- For greater bandwidth and even some gain over a dipole, make an Off-Center Fed Dipole (OCFD) rather than a dipole. Follow the instructions here in the RR Antenna Wiki -

Homebrewed Off-Center Fed Dipole - The RadioReference Wiki

The OCFD scanner antenna has extensive writeups here on RR (just use "OCFD" or "off-center" as your Search key). Here is but one of the many examples / writeups from people who've built and use the OCFD -
http://forums.radioreference.com/bu...67-my-homemade-off-center-dipole-antenna.html

- Since you plan to use the attic, do you by chance have any unused connections to old cable TV or satellite systems that were once installed in your house? It's not unusual for installers to use the attic as a path for TV coax. My house was wired with TV coax to most rooms and terminated in the attic. I put my OCFD in the attic and connected a CATV splitter amp and fed several of the coax runs to various rooms in the house. They were already terminated at a CATV outlet box in each room, so all I had to do was run a jumper cable from the wall jack to the back of the scanner to be able to put a scanner in the room and still have the advantage of an attic antenna. The cable TV splitter/amps are very broadband and work for scanners. The whole system works great for me.

 

[dmg1969]

Hello All and thank you.

I am excited to say I am going to build my own dipole (for my attic) as jonsmth and others have suggested... I might even have some of the stuff at home already... Thank you!

Sincerely,
Rich

Rich, I was going to post a link to my thread about making my own Off Center Fed Dipole (OCFD), but popnokick beat me to it. It is a relatively cheap, fun and quick project. It should take you no more than 30 minutes assuming you have the right tools.

There is one thing that I did not do correctly, but the effects are probably miniscule. When I attached the balun, I drilled two additional holes into the copper pipes (1 leg to the 18" and the other to the 48"). I was told I should have just used the two screws that attached both lengths of pipe to the center PVC T fitting. Again, the effects are likely minimal in comparison to the fun and satisfaction of having made your own antenna.

P.S. I just realized that I did not post about the reception. I can say that it does well on VHF low (low band), VHF (high) and UHF. I have nothing around that is 800 MHz, so I cannot attest to that.

 

[mikewazowski]

Thread moved to Scanner/Receiver Antennas.

 

[hotdjdave]

Here are a few to consider that may meet your needs:

• FM DX Antenna Co: Long Range Police Scanner Radio Outdoor or Attic Antenna, Scanner Antennas
• Indoor Dipole Scanner Antenna 25 1300 MHz w SMA Plug | eBay
• The Original Snoop Scanner Antenna
• Maxx Tenna in Outdoor Police Fire EMS Air Marine Scanner Antenna 20' Cable | eBay
• HG Base Scanner Antenna | eBay

Articles on the subject:

• A Stealthy Homebrew Vertical Dipole Antenna Using Strong Tie "T"'s
• Attic Antennas
• Scanner and Scanning Tips
• Attic Scanner Antenna | WoodCraft

PS. I have nothing to do with any of the above sellers or products.

Happy Scanning!

 

[justrfb]

OCFD...

Hello All.

hotdjdave. Thanks for the links... I will be getting the correct coax and connectors now.

Mike. Thanks for moving the thread to the correct place. Sorry... Still getting to know my way around here.

dmg1969. I am building my OCFD based on your post, thank you! I will be considering what you and others are suggesting too. Can't wait... Just got the copper tubing last evening with my wife Annemarie.

popnokick. Thanks again for your continued support in my many threads... I appreciate your help.

jim202. Thanks for the excellent explanation on pulling cable. I have pulled cable before so know a little about what you are talking about... Did not know about the fire stops though...

jonsmth. Thank you too. I appreciate your thoughts and suggestions about your OCFD too. I can't wait...

I will take pictures as I go and will post here my build thread on my OCFD attic antenna. I could not have done any of this without your help. Thanks!!

Sincerely,
Rich