Railroad Base Scanner Indoor Antenna Question

Status
Not open for further replies.
Joined
May 13, 2016
Messages
3
Hello All,

I'm looking to answer a series of questions to maximize my indoor base scanner setup, which with married life and a new house comes with certain restrictions. I'd like to listen to RR frequencies, which are in the 160-161MHz range, so nothing too crazy. I know the tower locations around me for the RR, and I do get some towers without problem, as expected. What I am lacking however, are hearing train crews and automated equipment detectors (which give you details about train movements, a great way to tell if a train is close by) and FRED frequencies, which are small data bursts on the train that run in the 101MHz. The nearest tracks are only 1 mile away, and typically with my mobile scanner I can pickup the FRED, Detector and tower channels no problem.

So the situation is I get a good chunk of the basement to have a hobby room (model trains of course). However, rules are no antenna outside on/around the house.... so I have a BC365CRS, rigged up with a cheap extension cable (maybe this could be an issue?) to a Smiley 160MHz antenna (4' telescope) and my question is what can I get for an antenna that will maximize my setup? The area my scanner is perched is up high, and there is a basement window close by away from any machine noise (computers, routers, ect). Also, does the orientation of my antenna make a big difference (vertical, horizontal, pitched, ect)?

Sorry for all the questions, I read through some other posts but determined that in reality each situation & setup is different. I am willing to invest in a good setup, ultimately I'd like to link up to Broadcastify and run a stream (maybe using a Raspberry Pi or other cheap computer)
 

lou9155

Member
Joined
Sep 10, 2007
Messages
345
Location
shamong nj
i sure do feel your pain with wifey mandated antenna restrictions. but unfortunatly an indoor antenna wont get you where you want to be with listening satisfaction. can you get an antenna outside in a stealth manner or a yagi mounted where it cant be seen? indoor antennas will not get those train ops. the best i could do was a discone mounted on 10 foot conduit pipe in a weighted umbrella stand...its kinda hidden from her view in the treees. luckily a rail antenna is kinda low profile maybe some krylon green camo paint ....might never be seeen
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
So the situation is I get a good chunk of the basement to have a hobby room (model trains of course). However, rules are no antenna outside on/around the house.... so I have a BC365CRS, rigged up with a cheap extension cable (maybe this could be an issue?) to a Smiley 160MHz antenna (4' telescope) and my question is what can I get for an antenna that will maximize my setup? The area my scanner is perched is up high, and there is a basement window close by away from any machine noise (computers, routers, ect). Also, does the orientation of my antenna make a big difference (vertical, horizontal, pitched, ect)?

Cheap coax can be part of the issue, but if it's a short cable, it's unlikely bad enough to be triggering all your issues.

Orientation of the antenna does matter. Ideally you want to match that of the transmitting antenna, which will be vertical.

An antenna in a basement, even near a window, is going to be problematic, really doesn't matter what antenna you use.

You need to get the antenna up as high as you can. While that might seem impossible with your current restrictions, there are ways to make it happen.
If you don't have a metal roof, you can sometimes put the antenna in the attic and get acceptable results. The challenge with that has to do with getting the cable from the basement to the attic. Look for existing cable paths that you can use, or route up the outside along rain gutters

Building a VHF dipole antenna and tacking up on the side of the house or under the eaves might be an option.

If none of those are an option, you might do better by putting the radio and antenna in an upstairs room with a window that looks in the direction of the rail line. Feed the audio down stairs using a bluetooth speaker, or wired external speaker.
 

allend

Member
Premium Subscriber
Joined
Feb 1, 2012
Messages
1,378
Location
Long Beach, CA
Okay. Here is your best bet. Buy a Ventenna from this company. This antenna is very stealth and make sure if you buy one that you get the one that runs the feed line down the inside of the vent pipe and run it through into your attic and cut and put a tee on it. You will not go wrong. Then you spray paint the outside of the antenna to make your roof

Ventenna
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
8,944
Location
Stockholm, Sweden
Read the Ventenna Eham reviews carefully https://www.eham.net/reviews/detail/1089
One guy received a faulty antenna from a friend and send it in for repair and before he got it back he gave it a 5 of 5.

"$84.00 for a piece of ABS pipe?
I went to Home Depot and purchased a 4 ft. length of 2" ABS and mounted a $10.00 100W Moldor 144/440 mag mount antenna purchased on eBay inside using 2 zip ties. (Had to drill a couple a of holes in the $2 ABS pipe)I then slipped it over an existing vent on top of my 2 story. Fit great. Ran the cable to my radio and was surprised at the performance. Good idea but can be home brewed for about $15 if you already have a lenght of cable.
"

/Ubbe
 

lou9155

Member
Joined
Sep 10, 2007
Messages
345
Location
shamong nj
i would never attach anything to a home DWV pipe. let alone drop a coax inside it . disaster waiting to happen esp if you dislodge your vent and possibly get waste water leaking or create a negative pitch...not good
 
Joined
May 13, 2016
Messages
3
Cheap coax can be part of the issue, but if it's a short cable, it's unlikely bad enough to be triggering all your issues.

Orientation of the antenna does matter. Ideally you want to match that of the transmitting antenna, which will be vertical.

An antenna in a basement, even near a window, is going to be problematic, really doesn't matter what antenna you use.

You need to get the antenna up as high as you can. While that might seem impossible with your current restrictions, there are ways to make it happen.
If you don't have a metal roof, you can sometimes put the antenna in the attic and get acceptable results. The challenge with that has to do with getting the cable from the basement to the attic. Look for existing cable paths that you can use, or route up the outside along rain gutters

Building a VHF dipole antenna and tacking up on the side of the house or under the eaves might be an option.

If none of those are an option, you might do better by putting the radio and antenna in an upstairs room with a window that looks in the direction of the rail line. Feed the audio down stairs using a bluetooth speaker, or wired external speaker.

Thank you all, some informative responses. Perhaps too I can go back and do some 'negotiations' now armed with more info. I have some ideas about how I can sneak a line outside and be stealth, perhaps if I come up with a solid proposal the boss will sign off ;)

The cheap coax line is about 8 feet long, perhaps ditch that? Any recommendation on a better coax extension line?
 

GROL

Member
Joined
Aug 29, 2017
Messages
573
If your roof has asphalt shingles and not metal, you can mount an antenna in the attic. I have a few in my attic and they work very well. Get it as high as you can and away from electrical wiring to avoid electrical noise. For your purpose, just a vertical dipole would work fine.

If your coaxial cable run is only about 50 feet or less, you will be fine for 160 Mhz.

At 160 MHz, 50 feet of RG-58 is about 3db loss which is not very bad at all, especially if you have that antenna up high in the attic. If you had no loss due to cable, you would not notice the difference at 3dB loss. That is only 1/2 S unit on a receive signal strength meter. If we were working at 800MHz, that 50 foot cable run would be a little more of a problem.


Times Microwave Cable attenuation calculator. Welcome to Times Microwave | Coaxial Cable - Attenuation & Power Handling Calculator


You will of course have the challenge of running the cable through a wall into the basement. Not an easy task, but doable. If you are lucky, there will be a closet nearby above the basement that you can run the cable through the ceiling in a corner of the closet and then through the floor into the basement.
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
Thank you all, some informative responses. Perhaps too I can go back and do some 'negotiations' now armed with more info. I have some ideas about how I can sneak a line outside and be stealth, perhaps if I come up with a solid proposal the boss will sign off ;)

Negotiations with the Minister of War and Finance can be tricky. If we don't hear back from you, we'll assume the worst.

The cheap coax line is about 8 feet long, perhaps ditch that? Any recommendation on a better coax extension line?

I highly doubt that's the issue. Even crappy Chinese coax isn't going to be -that- bad at 8 feet long. Switching out to a high grade coax will not have any noticeable effects.
 
Joined
May 13, 2016
Messages
3
Negotiations with the Minister of War and Finance can be tricky. If we don't hear back from you, we'll assume the worst.



I highly doubt that's the issue. Even crappy Chinese coax isn't going to be -that- bad at 8 feet long. Switching out to a high grade coax will not have any noticeable effects.

Thanks for the blessing!

I do have a crawl space behind a knee wall in the new house on the second floor... perhaps this space is suitable for an antenna? Can I just use whatever coax is laying around, such as that to transmit 70-channels of garbage to my TV, as long as I put on the right fitting (BNC I believe)?
 

JoshuaHufford

Member
Feed Provider
Joined
May 27, 2018
Messages
694
Location
Jefferson City, Mo

JoshuaHufford

Member
Feed Provider
Joined
May 27, 2018
Messages
694
Location
Jefferson City, Mo
Another thought.

Do you know of any other Rail Fans in the area? You mentioned wanting to broadcast it, there may be someone in the area that has a great location for receiving and willing to host the equipment, just might not have the funds for the equipment. If your broadcasting over the net who cares where the equipment is as long as you can listen to it.

Sometimes when you pool resources you can accomplish a lot more.
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
Thanks for the blessing!

I do have a crawl space behind a knee wall in the new house on the second floor... perhaps this space is suitable for an antenna? Can I just use whatever coax is laying around, such as that to transmit 70-channels of garbage to my TV, as long as I put on the right fitting (BNC I believe)?

That would very likely work better than having the antenna in the basement.

Any coax will work. 75Ω TV coax will work fine.

You don't need much of an antenna for VHF. The one you are using will probably work sufficiently. As Krokus said, even a TV antenna will work.
You can even just strip back the coaxial cable, leaving 18 inches of exposed center conductor and have a basic 1/4 wave antenna.

You can always spend more on antenna, but get what you have out of the basement first, see how it works, then decide.
 

GROL

Member
Joined
Aug 29, 2017
Messages
573
A TV antenna that receives VHF TV channels can work, but the antenna should be oriented vertically and not horizontally. There can be as much as a 20db drop in signal with the receive antenna oriented opposite of the transmit antenna in this frequency range. Land mobile radio antennas are vertically oriented. Also the antenna will be directional, since TV antennas are either a Yagi or Log Periodic type of directional antenna. You would want to use any TV antenna with the least number of elements if you want it to perform more omnidirectional.
 

trp2525

Member
Joined
Mar 31, 2010
Messages
1,290
...I'd like to listen to RR frequencies, which are in the 160-161MHz range...

my question is what can I get for an antenna that will maximize my setup?...

If you have some room in the attic or near a window on an upper floor (highest is best), you might want to consider a 1/4 wave ground plane tuned for the railroad frequencies. You could make one yourself or consider Centerfire Antenna which makes one that is tuned to 150-165 MHz which covers the railroad band. It's made (in the USA) of aluminum and stainless steel, has an SO-239 connector (which mates with a PL-259 connector), has a "Limited Lifetime Warranty" and is reasonably priced at $29.95 (plus $8 shipping): https://centerfireantenna.com/antenna-menu/vhf-receiving-antennas/

A second option from Centerfire Antenna would be their Scanner Dipole. They have one that covers 156-165 MHz and it uses a 300-ohm to 75-ohm matching transformer that has an F connector (standard cable TV connector) to hook up to your coax. The price is $31.95 (plus $8.00 shipping): Scanner Dipoles – US Dipole
 

GROL

Member
Joined
Aug 29, 2017
Messages
573
If you have some room in the attic or near a window on an upper floor (highest is best), you might want to consider a 1/4 wave ground plane tuned for the railroad frequencies. You could make one yourself or consider Centerfire Antenna which makes one that is tuned to 150-165 MHz which covers the railroad band. It's made (in the USA) of aluminum and stainless steel, has an SO-239 connector (which mates with a PL-259 connector), has a "Limited Lifetime Warranty" and is reasonably priced at $29.95 (plus $8 shipping): https://centerfireantenna.com/antenna-menu/vhf-receiving-antennas/

A second option from Centerfire Antenna would be their Scanner Dipole. They have one that covers 156-165 MHz and it uses a 300-ohm to 75-ohm matching transformer that has an F connector (standard cable TV connector) to hook up to your coax. The price is $31.95 (plus $8.00 shipping): Scanner Dipoles – US Dipole

Those are reasonably priced ground plane antennas. The one for 150 - 165 MHz would do a good job in the attic as long as the roof is not metal. As mentioned before, even 50 feet of RG-58 would not present enough loss to matter.
 

trp2525

Member
Joined
Mar 31, 2010
Messages
1,290
...even 50 feet of RG-58 would not present enough loss to matter.

I would opt for RG6 coax which has lower loss than RG-58. You can purchase a 50-foot length of quality RG6 coax (solid copper center conductor) with quality compression connectors installed on each end for $16.99 from Solid Signal: https://www.solidsignal.com/pview.asp?p=SSCBLS

At the antenna end you could use an F-to-PL-259 adapter assuming the selected antenna has an SO-239 connector. If the selected antenna has an F connector, like the Scanner Dipole antenna referenced in my post above, an adapter would not be needed. At the scanner end you could use an F-to-BNC adapter (https://www.theantennafarm.com/catalog/rfi-rfb-1155-5995) to connect to the scanner/radio.
 

GROL

Member
Joined
Aug 29, 2017
Messages
573
I would opt for RG6 coax which has lower loss than RG-58. You can purchase a 50-foot length of quality RG6 coax (solid copper center conductor) with quality compression connectors installed on each end for $16.99 from Solid Signal: https://www.solidsignal.com/pview.asp?p=SSCBLS

At the antenna end you could use an F-to-PL-259 adapter assuming the selected antenna has an SO-239 connector. If the selected antenna has an F connector, like the Scanner Dipole antenna referenced in my post above, an adapter would not be needed. At the scanner end you could use an F-to-BNC adapter (https://www.theantennafarm.com/catalog/rfi-rfb-1155-5995) to connect to the scanner/radio.

That is a good find on the RG-6 with connectors. It won't make a huge difference, but it would be 1.7dB loss vs. 2.9 dB for RG-58. Only issue is RG-6 is thicker and more rigid. It is easier to damage if you accidentally put a tight bend into. It won't straighten back out as well as RG-58. I would give the RG-6 a try, but just be careful not to pull on it hard if it gets snagged somewhere while routing it. I have used a lot of RG-6 for UHF and 800 MHz reception where it makes a much bigger difference in loss.
 

cbehr91

Member
Premium Subscriber
Joined
Jun 22, 2010
Messages
419
Get the largest non-stick cookie sheet you can find, and just use a 1/4 wave or tri-band scanner antenna on an NMO mag mount. It sounds silly, but it works. I have used one with the cookie sheet sitting on a ceiling joist in the attic. If you want something more permanent, go with the 1/4 wave ground plane and 50-ohm coax. I know it's a age old argument among scanner buffs, but I've just never gotten onboard with using 75-ohm coax for a scanner which specifies a 50-ohm input.

A word about the Centerfire dipoles. They may work well, but a dipole like that will have a feedpoint impedance of 60-70 ohms, so if you use 75-ohm coax you will have loss at the radio end. If you use 50-ohm coax you will have loss at the antenna end. Will you notice it? Perhaps not, but it could also mean the difference between hearing that distant transmission and not. A folded dipole will match better (or a 1/4 wave GP with the radials drooped around 43 degrees).

Just some food for thought.
 
Last edited:
Status
Not open for further replies.
Top