Bearcat BC150 - ZDC ARTCC

[JLHDU]

New here....I've been reading various posts throughout the site for a couple of hours now. Wondering if any of you can fill in the blanks...I'm considering the purchase of a Bearcat BC250D. I also read there is an additional card available.

I'm an air traffic controller at Washington Center (ZDC) and would like to be able to monitor the frequencies from home or while commuting to and from work (Leesburg, VA to Odenton, MD). However the Antenna sites that my sectors broadcast are pretty far away (ie... Bedford, VA - Plaines, VA and Benson, NC). I'm not even sure if I can monitor them from work (Leesburg, VA) or home (Odenton, MD). Would the Bearcat be the best. Guess I would also like to have the option to listen to other police, fire, etc....freq's as well. I also am wondering if there is antenna for the handheld that I would need to reach these areas. This may be a dumb question but can a scanner dial in a (ex. VHF 122.085 freq. or a UHF 342.045 freq.?) or can it only go two decimals (ex. 122.03?)

I've been looking for any kind of charting showing the frequency coverage but haven't located anything yet. Any help would be greatly appreciated. Thanks in advance.

-J

 

[Al42]

This may be a dumb question but can a scanner dial in a (ex. VHF 122.085 freq. or a UHF 342.045 freq.?) or can it only go two decimals (ex. 122.03?)

Since the bandwidth of the receiver will probably exceed 12 KHz, tuning to the nearest 5 KHz isn't really necessary. But most modern scanners will be able to tune to all the actual channels. (Not every frequency is a channel.)

 

[JLHDU]

Thanks...Do you recommend the Bearcat handheld?

 

[ka3jjz]

Please see the Scanning Forum under the similar topic for some important information....73s Mike

 

[inigo88]

Hi how are ya, I'm a student pilot in northern california and I have a scanner I bought from Sporty's Pilot Shop that works great (it's discontinued it's called a JD-100 but they make a newer one). That being said it's a little overpriced for what it does and I think the BC250D would suit your needs as you can listen to Center and also hear other pertinent information related to your commute (police/fire/highway patrol/traffic reporters/people on cb radios etc.). Do you know anyone at ZDC that can give you the locations of the RCAG transmitters in the sectors you'll be listening to? I doubt you could get ahold of any map that would show what areas they cover on the ground because the antennas tend to radiate upwards (air to ground after all... as opposed to public safety repeaters which will point down at the surrounding area), so the higher up the antenna is and whether you can get within line of sight of it (easier to do when you're closer to the site) will be a factor in you hearing the controller. You'll hear the pilots regardless, and a lot of information like PIREPs and how congested the airspace is can be discerned just by listening to that side of the conversation.

I hope I could help,

-Inigo

 

[wadeless28]

Welcome to the neighborhood J,
I am a bit closer (about 3/4 of a mile north of route 32) to BWI then you, so I do have good luck picking up the SWANN sector ground transmissions along with controllers working in the tower and Potomac Tracon. All with just a rubber duckie antenna. If you are located in one of the higher neighborhoods of Odenton you might have the same luck with the Bearcat. But I would recommend an outdoor or attic antenna to insure better reception.

Mike

 

[kc4jgc]

I'm an air traffic controller at Washington Center (ZDC) and would like to be able to monitor the frequencies from home or while commuting to and from work (Leesburg, VA to Odenton, MD). However the Antenna sites that my sectors broadcast are pretty far away (ie... Bedford, VA - Plaines, VA and Benson, NC). I'm not even sure if I can monitor them from work (Leesburg, VA) or home (Odenton, MD). ...........

I've been looking for any kind of charting showing the frequency coverage but haven't located anything yet. Any help would be greatly appreciated. Thanks in advance.

-J

I'm afraid that if you are only interested in the sectors you normally work that you'll be out of luck no matter what scanner/antenna you have. The closest ZDC site to me is in southern part of Suffolk VA (Whaleyville); I might be able to hear the pilots but won't hear the controllers unless I fairly close (within 5 miles or so). Another ZDC site I drive by from time to time (Green Bay VA) is pretty much the same.

On another subject, do you use the HF log periodic at ZDC often? Why is it always pointed west? I would have thought it would be pointed east or northeast to monitor trancontinental flights to/from Europe.

 

[JLHDU]

On another subject, do you use the HF log periodic at ZDC often? Why is it always pointed west? I would have thought it would be pointed east or northeast to monitor trancontinental flights to/from Europe.

I'm not sure. I'll check this weekend.

 

[JLHDU]

Welcome to the neighborhood J,
I am a bit closer (about 3/4 of a mile north of route 32) to BWI then you, so I do have good luck picking up the SWANN sector ground transmissions along with controllers working in the tower and Potomac Tracon. All with just a rubber duckie antenna. If you are located in one of the higher neighborhoods of Odenton you might have the same luck with the Bearcat. But I would recommend an outdoor or attic antenna to insure better reception.

Mike

I'm in Piney Orchard so hopefully I'll have some luck. I usually work Linden, Cassanova, Valley & Hot Springs, Marlinton and South Boston. I'll probably only have luck hearing Linden and Cassanova. When I drive up Rt. 32 then onto Rt. 70 and down Rt. 15 on my way to work I'll probably have better luck.

-J

 

[JLHDU]

Do you know anyone at ZDC that can give you the locations of the RCAG transmitters in the sectors you'll be listening to? I doubt you could get ahold of any map that would show what areas they cover on the ground because the antennas tend to radiate upwards (air to ground after all... as opposed to public safety repeaters which will point down at the surrounding area), so the higher up the antenna is and whether you can get within line of sight of it (easier to do when you're closer to the site) will be a factor in you hearing the controller.
-Inigo

Our pubs have the RCAG lists. That's easy to find, but finding a map showing ground coverage may be more difficult. I'll let you know what I find.

-J

 

[wa8vzq]

The log periodic antenna at ZDC is for the FAA NARACS HF network which is a command network that interlinks the centers, the NOCC - National Operations Command Center, the regional offices and other FAA facilities. FAA air traffic controllers do not control aircraft using HF radio. The operators that you hear on HF id'ing as New York Radio or San Francisco Radio are employees of ARINC. They relay clearances and collect position reports to the associated centers. So that's why the antenna isn't
pointed in the direction that you think it should be pointing.

 

[wa8vzq]

For the most part, unless you are within 10-15 miles of an RCAG, you're not going to hear the controller end of the transmission. It is mainly an line of site issue and has nothing to do with radiating straight up. A typical RCAG antenna tower is 40-50 ft tall and the transmitters typically run either 10 watts or 50 watts depending upon the site. The towers are lower to the ground to prevent nulls or holes in the radiated signal.

There is nothing in the design that forces the radiation upward likewise there is nothing in the design of a two-way radio system antenna that forces the radiation downward - two way public service facilities are sited to provide the best fit ground coverage and RCAG's are sited for the best fit for the service volume. The reduction in signal strength on the ground is a naturally occurring by product of the height above ground and the combination of thedirect wave and the ground reflected wave cancelling - basic radio propagation theory. This occurs in public service systems as well but they do their best to minimize the effect by making the antenna tower higher.

 

[JLHDU]

Thanks...I guess the site at the Linden (LDN) VOR transmitter is about the only one I'll be able to pick up?

-J

 

[wa8vzq]

The VOR will get very boring after about 15 seconds ;-)) From looking at the RCAG sites within your airspace, it's looking a little sparse for you in Odenton. You will of course be able to hear the a/c from a long way out. This is pretty typical and is also the cause for a lot of misconceptions about how air traffic comm works since most listeners usually can't hear more than one or two RCAG's and that is if they are lucky.

There is a whole bunch of milcom activity in your area which should be highly entertaining. One of the reasons that I like to listen to milcom is because you can often hear both sides of the conversation, especially true in gunnery activity in MOA's, AWACS and refueling missions and it's often more interesting than "cross at maintain one zero thousand" that you find in civilian traffic. (no offense intended, just an observation) You may want to have a look at that aspect of the hobby. You might find it interesting to see what those boys that you are vectoring around are really up to ;-))

Dan

 

[JLHDU]

We have a transmitter co-located at the Linden (LDN) site. Biggest problem is when we have high climbers (ex. SWA) over the vor, there is a dead spot. We tend to lose them for almost 5 miles one either side.

 

[wa8vzq]

That's not unusual. If you look at this link, there is a graph at the bottom of the page that shows the vertical radiation pattern of a typical antenna used at an RCAG site. You will see that there is a null that gets 10-20 dB deep between 70 and 90 degrees. The actual depth of the null is directly related to the height of the antenna above ground. The technical name is the radio cone of silence, not to be confused with the cone of silence from the 'Get Smart' TV show of the 60's. It's real and it is caused by the fact that the signal that comes directly from the antenna and the signal that bounces off the ground cancel each other out at that point in space. When an aircraft passes directly over a VOR, the flag that comes out on the OBI (omni-bearing-indicator) is caused by a similar reason. All antennas exhibit this to some amount, the trick is to design the facility to minimize the impact on the users.

http://www.tacocommunications.com/FAAApproved.pdf

Dan

 

[JLHDU]

Ok...I just had a few minutes,

Primary freq for Linden, VA (LDN) is 120.65/319.1 -Sector 05 (BWI, IAD and DCA Metro Departures)
The BUEC Priority: VHF and UHF are paired.
Priority 1: ZDC
priority 2: Fredrick VOR
Priority 3: Kessel VOR/DME

 

[DPD1]

I have a friend who likes his 250D. He's primarily into VHF/UHF Air. He doesn't have any digital near him, so he didn't get the card.

If you think reception is going to be an issue for you, you might want to consider a mobile/desktop. The point being that if you decide to use an external antenna, a mobile can often handle that better than some handhelds. A lot of the handhelds are designed with the thought that people won't use big antennas, just the small kind. So sometimes you can have problems hooking them up to bigger antennas.

I don't know the distance from your home to the nearest transmitters... But If you have a good external antenna at home, you should be able to pick up AC side from at least 75 miles away, when they are above 10k or so. Assuming you don't have any mountains in the way or anything.

I live right in the middle of ZLA, and I barely get a few transmitters ground side. And that's with good antennas two stories up. So the ground side is hard to get on any level.

Dave
-DPD Productions - Featuring the MilTenna LP Gain Scanner Antenna-
http://eje.railfan.net/dpdp/

 

[JLHDU]

That's another issue I am gonna have to tackle. The way the crow flies it's about 50 miles to LDN. I'm sure I can get all the BWI and Potomac freq's.

If I were to buy one of the handhelds...could I also have an antenna hooked up via a wire and attach it from the handheld to the wire to a trunk mount?

If any of you are looking for a specific ATC freq be it military/civil check out...

www.stuckmic.com

I'm sure those guys can get pretty much any atc freq you need.

 

[DPD1]

Yeah, that's no problem... You just put a BNC on the end of the cable and attach it where the antenna goes. A mobile antenna should be fine, but anything bigger than that and some handhelds can't deal with the extra signal level coming in... So sometimes you'll get interference and a lot of intermod.

Dave
-DPD Productions - Custom Scanner, MURS, & Ham Antennas-
http://eje.railfan.net/dpdp/