Base station scanner setup for room

[batbou444]

I'm currently thinking about getting a base station setup for my room in my house, it consists of a uniden sds200, and the DPD Productions Omnix antenna. Is there anything I should address before putting in the orders and what coax cable should I use (ill likely have to run the cable outside).

 

[chief21]

The optimal coax selection will depend on the total run (in feet) from the scanner to the antenna and what your goals are (local monitoring, extreme distance monitoring, etc. Also, the primary frequency bands you intend to monitor (VHF, UHF, 700-800), the typical strength of those primary signals (urban, suburban, rural; distance to signal sources), and any financial considerations. Possibilities could range from inexpensive cable tv coax all the way to premium, very low-loss coax.

 

[batbou444]

The optimal coax selection will depend on the total run (in feet) from the scanner to the antenna and what your goals are (local monitoring, extreme distance monitoring, etc. Also, the primary frequency bands you intend to monitor (VHF, UHF, 700-800), the typical strength of those primary signals (urban, suburban, rural; distance to signal sources), and any financial considerations. Possibilities could range from inexpensive cable tv coax all the way to premium, very low-loss coax.

The total run for coax in feet is likely going to be from 40-80 ft and the farthest I want to go is 700mhz band for P25, and also railband, aviation, probably some other ones too.

 

[mmckenna]

Good info from Chief.

I'll add a few things:
All outdoor coax connection need to be waterproofed, no exceptions. RFS CTAPE2-1 Weatherproofing Tape
Failing to properly waterproof the connections will result in moisture getting in the connectors/cable. Doesn't have to be rain, moisture will condense on the cold metal. Any water in the connectors/coax/antenna port will corrode and destroy them.

You should really read up on proper National Electric Code lightning protection for outdoor antennas. Not hard to do, but it's much easier to do correctly if you plan for it before installation.

Get the antenna up as high as you safely can. Most of the radio signals you want to hear are line of sight. The more the antenna can see, the more you can hear. But safety is important and should come first.

Good coax is important. There are a lot of good options based on your budget. Like Chief said, there's a lot of options. Knowing how long your run will be, the kind of listening you'll do, and what your budget is will help others give good recommendations on what cable options may be right for you.

 

[wtp]

if you might only listen to local stuff, you might not have to go outside at all.
i live in Florida and don't want any outside stuff because of lightning.
but i only listen to my counties trunked system, so the back of the set/rubber duck work for the base or handheld.

 

[IC-R20]

The total run for coax in feet is likely going to be from 40-80 ft and the farthest I want to go is 700mhz band for P25, and also railband, aviation, probably some other ones too.

RG11 quad shield. You can also put a preamp at the base of the antenna to negate the slight line loss if you really wanted to.

 

[mmckenna]

The total run for coax in feet is likely going to be from 40-80 ft and the farthest I want to go is 700mhz band for P25, and also railband, aviation, probably some other ones too.

Coaxial losses go up as frequency increases, so design your coax run around your highest frequency.
Coax loss also goes up with cable length, so keeping the run as short as possible will reduce losses and save you money.

RG-11, as mentioned above, can be a good choice. At 800MHz and 40 feet, you'll have about 1.8dB of loss, which isn't bad. Challenge with RG-11 is finding connectors, crimp tools, and strippers. Not impossible, but not as easy as some other cables. RG-11 is often used by cable TV companies or long satellite TV runs. Unless you have a friend that works for the cable TV company, you'll need to order everything you need. A thicker cable that can be stiff and difficult to run in residential installs, and you don't want to connect directly to the scanner as that'll put a lot of stress on the antenna jack, possibly causing damage.

RG-6, which is a common cable TV/Satellite TV cable will have a bit over 3dB of loss over 40 feet. That's a bit much, but not an issue if you are listening to local traffic or you add an amplifier. Nice thing is RG-6 is cheap and easy to get at hardware stores. Easy to find strippers, connectors and crimpers there, also. Your local Home Depot, Lowes, etc. will have what you need.

Times Microwave LMR-240 will be a bit better than RG-6. You can order pre-made cables with the connectors you need from various sources, like www.theantennafarm.com as well as others. Easier/cheaper to order the cable with the connectors already installed rather than buying the tools to do it yourself.

Times Microwave LMR-400 will be better than the RG-11 by a bit. You'd want to order premade cables as the tools to properly install connectors on this will be expensive. This is a heavy/stiff cable that will be difficult to run. You also do not want to connect this directly to your radio as the stiffness can result in damage to your scanners antenna jack. You'd want to use a short run of more flexible cable to act as an adapter between the LMR-400 and scanner.

There's higher grade cable than these, but you are getting into expensive stuff, measured in dollars per foot.

If you move your antenna up higher, you'll get a bit more range. But you'll add cable length and losses. Longer cable runs benefit from higher grade cables.

So, as I said above, it can come down to what your budget will allow. Usually LMR-400 is about the limit for most hobbyists due to cost, stiffness, and difficulty routing. LMR-240 might be a better option if you get a strong signal outside.

 

[Ubbe]

RG6 are produced in such a huge amounts as it will be the most cost effective coax to use and will be easy to work with and use cheap twist on connectors that needs no special tools. Then for scanner connection it would probably be wise to use RG174 pig tails, at least for portable scanners.

Its 75 ohm impedance isn't a problem as Omni-X doesn't have a 50 ohm impedance over its frequency ranges and the same goes for a scanner. RG6 has often quad shield that ensures that no interference from house appliances can enter directly into the coax.

After the installation you can look at the signal strength values in dBm on the scanner and decide if a 3dB difference will make it worthwhile to replace a RG6 coax with a much more expensive one. But then it's going to be cheaper and have a bigger impact on weak signals to use an antenna amplifier. It will work as a buffer, loading the antenna with a constant impedance and the same for the coax as well as amplifying weak signals. In most situations a scanner will overload more quickly than what the antenna amplifier will do.

/Ubbe

 

[kc2asb]

If you have an attic or crawl space, you might be able to compromise between a back-of-the set antenna and an outdoor installation. I have all of my scanner antennas installed in an eve under the roof in the attic. It's a wood-frame house with a shingle roof, so attenuation of the signals does not seem to be a major problem. The antennas and feedlines are out of the elements and will last indefinitely.

The Omni X is compact enough to use in an attic / crawl space installation.

I live next to RF Alley (NYC) - with an outdoor antenna, I have experienced overload issues. If you live in a rural / fringe area, an indoor antenna may not provide satisfactory performance.

 

[APX8000]

I have your exact setup (an Omni-X going to an SDS-200). Only difference is I have a Minicircuits AM trap right at the antenna and a multicoupler splitting the signal to 3 other scanners. I'm using Times LMR-400 UF with N-male connectors. Run is about 50 feet and right now its in the attic. I have elevation on my side here, but you won't be disappointed.

 

[batbou444]

Coaxial losses go up as frequency increases, so design your coax run around your highest frequency.
Coax loss also goes up with cable length, so keeping the run as short as possible will reduce losses and save you money.

RG-11, as mentioned above, can be a good choice. At 800MHz and 40 feet, you'll have about 1.8dB of loss, which isn't bad. Challenge with RG-11 is finding connectors, crimp tools, and strippers. Not impossible, but not as easy as some other cables. RG-11 is often used by cable TV companies or long satellite TV runs. Unless you have a friend that works for the cable TV company, you'll need to order everything you need. A thicker cable that can be stiff and difficult to run in residential installs, and you don't want to connect directly to the scanner as that'll put a lot of stress on the antenna jack, possibly causing damage.

RG-6, which is a common cable TV/Satellite TV cable will have a bit over 3dB of loss over 40 feet. That's a bit much, but not an issue if you are listening to local traffic or you add an amplifier. Nice thing is RG-6 is cheap and easy to get at hardware stores. Easy to find strippers, connectors and crimpers there, also. Your local Home Depot, Lowes, etc. will have what you need.

Times Microwave LMR-240 will be a bit better than RG-6. You can order pre-made cables with the connectors you need from various sources, like www.theantennafarm.com as well as others. Easier/cheaper to order the cable with the connectors already installed rather than buying the tools to do it yourself.

Times Microwave LMR-400 will be better than the RG-11 by a bit. You'd want to order premade cables as the tools to properly install connectors on this will be expensive. This is a heavy/stiff cable that will be difficult to run. You also do not want to connect this directly to your radio as the stiffness can result in damage to your scanners antenna jack. You'd want to use a short run of more flexible cable to act as an adapter between the LMR-400 and scanner.

There's higher grade cable than these, but you are getting into expensive stuff, measured in dollars per foot.

If you move your antenna up higher, you'll get a bit more range. But you'll add cable length and losses. Longer cable runs benefit from higher grade cables.

So, as I said above, it can come down to what your budget will allow. Usually LMR-400 is about the limit for most hobbyists due to cost, stiffness, and difficulty routing. LMR-240 might be a better option if you get a strong signal outside.

Would I be able to have something like a LMR400 cable that would go into a more flexible cable that goes into my scanner or would that degrade performance?

 

[APX8000]

I use 12-inch RG-400 jumpers. No issues.

 

[mmckenna]

Would I be able to have something like a LMR400 cable that would go into a more flexible cable that goes into my scanner or would that degrade performance?

If you are going to run any of the LMR-400 or larger variants, you absolutely want to use a short whip of more flexible cable to connect directly to the radio. Like I said, the LMR-400 is stiff and will snap the antenna connector off your radio if you are not careful.

The additional connectors and cable will add a negligible amount of additional loss, but that small amount of loss is WAY less than the loss of breaking off the antenna jack. It's well worth it to do the jumper.

You want to limit the use of adapters, if you can, so plan accordingly. The antenna end of the cable needs an N male connector, so might as well order your cable with male N's on each end.

For the jumper to your radio, get a cable made up that has a FEMALE N on one end, and a BNC Male on the other end. Use a suitable length to reach the radio.

As for what cable you use, there's a lot of options, and truth is for a run that short, most will work fine. RG-58 is inexpensive and flexible. RG-400 is a good option, but will cost you a bit more. RG-142 is a good option, also. You can also use Times Microwave LMR-195 or LMR-200. Don't get too hung up on the cable type. For such a short length, you will not be able to hear the difference. If it was me, I'd use the LMR-195, but you do you….

 

[batbou444]

If you are going to run any of the LMR-400 or larger variants, you absolutely want to use a short whip of more flexible cable to connect directly to the radio. Like I said, the LMR-400 is stiff and will snap the antenna connector off your radio if you are not careful.

The additional connectors and cable will add a negligible amount of additional loss, but that small amount of loss is WAY less than the loss of breaking off the antenna jack. It's well worth it to do the jumper.

You want to limit the use of adapters, if you can, so plan accordingly. The antenna end of the cable needs an N male connector, so might as well order your cable with male N's on each end.

For the jumper to your radio, get a cable made up that has a FEMALE N on one end, and a BNC Male on the other end. Use a suitable length to reach the radio.

As for what cable you use, there's a lot of options, and truth is for a run that short, most will work fine. RG-58 is inexpensive and flexible. RG-400 is a good option, but will cost you a bit more. RG-142 is a good option, also. You can also use Times Microwave LMR-195 or LMR-200. Don't get too hung up on the cable type. For such a short length, you will not be able to hear the difference. If it was me, I'd use the LMR-195, but you do you….

Alright thanks!