Indoor Scanner Antenna Advice

[Scott Greczkowski]

I have a Uniden Bearcat BCT15X scanner which I use at my office to rebroadcast the Newington, CT police Department. (You can tune in at http://weather.satelliteguys.us/wxpoliceradio.php)

My office is approximately 8 miles away from the police antenna site. It is located on the 30th floor (top floor) of an office building and I have almost line of site to their tower. The building is about a 30 year old Skyscraper, so lots of metal in the walls.

The frequencies the department uses are a trunked group from 460.00 - 463.00Mhz. They use LTR for their trunking system.

For the most part I pick things great. However there are times when broadcasts have some static in them, while this could be expected from their mobile units sometimes the dispatch is full of static as well. I want to clean up the audio more since so many people listen to this feed.

I am looking for an indoor antenna to use in my office so that I can improve reception. I am currently using the metal antenna which came with the scanner.

Not sure if something like this will help improve reception or not. http://www.scannerworld.com/ant135bnc/

Any ideas? Thanks!

 

[spongella]

Scott,
If you are interested in picking up those frequencies (460 - 463 MHz) specifically, you might want to try a 440 MHz beam antenna, like the hams use. You can even make one up using the plans in the ARRL antenna book.

Or you can make yourself a ground plane antenna for that band. If you Google 440 MHz ground plane antenna you'll see that it consists of a 19 inch radiator and four 20 inch radials. it is small enough to be made from a SO-239 chassis mount.

As for the scanner world antenna, am not familiar with that one. When I was limited to indoor antennas I found that a beam antenna worked the best. You just rotate it in the direction that brings the signal in the best.

Another source of scanner antennas is Universal Radio, Inc.

Sponge

 

[Scott Greczkowski]

Thanks but an antenna that big wouldn't be practical in my office.

 

[T134]

Scott, I've got two rat shack recommendations for you.

This one I've had since a kid and used on my Uniden Bearcat handheld, my frequency counter and it even transmits well on 2 meter with my wouxon. Basically adjust the length for the band you want to transmit on. For scanner Rx you can extend or not extend it however and it works very well. http://www.radioshack.com/center-loaded-telescoping-whip-antenna/2000006.html#.VOPjO3ufKMw

This takes up more space but isn't too big. I got this for something quick I could setup and hit some 2 meter repeaters with the wouxon from out in the sticks. It did decent for Tx but was really awesome for scanning a huge range. Be perfect for 460/463MHz reception especially as close as you are. Probably overkill. http://www.radioshack.com/outdoor-vhf-hi-uhf-scanner-antenna/2000176.html#.VOPjfHufKMw

 

[KE4EST]

I would just make you simple cheap center fed dipole with coax and tack it up on the wall and be done.

 

[spongella]

I hear you about large antennas at work.

At work in my cubicle I have some home brew antennas and other electronics trinkets such as LNBs, tubes, old radio parts - the staff has written me off as the "weird radio guy." But when we have an emergency drill practice, they appoint me the radio communications officer and know they can count on me to get the job done.

OK, here are some small Yagis I made from plans in the ARRL handbook and from other sources, with a yardstick included in the pic to show the sizes. Top is a 450 MHz 6 el, middle is an 800 MHz 8 el (for 800 MHz police band), and a 950 MHz 10 el for misc. intercepts. Boom is 1/2 inch schedule 40 PVC and elements are made from welding rod. These work well indoors, but bet they would kick butt if outside on a rotor, could probably put all 3 on one mast they are so light.

 

[kc1ih]

Or you can make yourself a ground plane antenna for that band. If you Google 440 MHz ground plane antenna you'll see that it consists of a 19 inch radiator and four 20 inch radials. it is small enough to be made from a SO-239 chassis mount.

Wrong! Those are the dimensions for a two meter (144-148 MHz) antenna, one for 440 MHz would be about one-third that size.

 

[spongella]

kc1ih is correct and I thank him for bringing it to light....

Yep, my apologies, that is for a 2 meter. A 440 MHz would have a radiator about 6 and a half inches with radials about 6 and three quarter inches. That is a pretty small antenna.

A thousand lashes with a wet noodle await me......

 

[spongella]

Okay, here's a neat little antenna made for around 465 MHz reception, using copper wire soldered to a chassis mount SO-239 connector. Made this a while back for work and used in the UHF band. Nice and small. You can attach a string to the radiator and hang from the ceiling.

Radiator = 150 mm
Radials = 165 mm

 

[Cham]

I use a Diamond D-130J on my BCT15X, works great for the 800 and 900MHz bands, can p/u towers 20mi away easily. It's up about 20' on a side-mount bracket off my tower. Radials are a bit cumbersome.
With that receiver you can tap the DCR audio to decode P25 and other modulations with the proper software.

spongella, we call that a "twinky" antenna. It's a 1/4 wave vertical at the frequency it's cut for. Will work fine for both transmitting and receiving. You can add other bands to the antenna by soldering different 1/4 wavelength radiators to the center pin; say 150MHz (17") 460MHz (6") and 800MHz (3.5"). You can actually transmit on each band if you want, should match 50 ohms at the right frequency. The radials should be 1/4 wave of the lowest (longest) frequency plus about 3%. Gain is 0 compared to isotropic, but still works good and cost can be almost nill if you have feedline and a solder gun.