Unknown Freqs

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Gary335

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I have a list of frequencies that I've heard activity on but can't identify. Below is a list of some of those frequencies. I'm hoping to find the identity of these frequencies so that I can decide whether their of any interest to me or not. Keep in mind while reading these that I'm rather new to scanning, so I don't know all the frequencies very well just yet. I have checked the database, as well as Radioshack's Police Call book, but still could not identify these frequencies. Also, I'm in Baltimore Co. using a Pro-94 from Radioshack, if that might give you a better idea of what I could possibly be hearing. Here they are:

143.985 451.300 856.387
143.990 464.000 856.637
147.135 463.175 816.000
147.525 460.387 855.537
147.025 464.400 856.012
147.030 464.775 856.162
151.745 496.887 860.212
 

Gary335

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OldHick said:
Have you checked out the database on this site for your county or neighboring counties? You can do a search on the FCC website FCC General Menu Reports version 2.1.20
http://svartifoss2.fcc.gov/reports/index.cfm this stuff takes time but it's interesting.

I'm pretty sure I mentioned that I did check the database. I have not however searched on the FCC website. I will give that a try.
 

Gary335

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I'm not etting anywhere at the FCC search page.....most likely because I haven't any idea what I'm doing. The reason I asked here was because I thought someone might know. I've already checked all the databases, books, etc. Had I not, I wouldn't be asking here yet.
 

ka3jjz

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Pretty easy to identify some of these; the 147 mhz freqs are hams; 147.135 is the Columbia ARA repeater, 147.03 is the Baltimore Radio Amateur TV Society repeater. 147.525 could be being used as a simplex or remote base frequency. 463.175 is a Med channel. The 800s are all outputs of a trunk system, except for 816.0 which is an input to a 861.0 (offset is always 45 mhz) trunk.
147.025 is 147.03 when not tuned in properly. 143.99 (and 143.985, which is .99 not properly tuned) might be a National Guard frequency. 496.887 is probably a police freq, but off the top of my head I'm not sure which. The other freqs are probable businesses, altho there could be a couple of police freqs mixed in there as well.
73s Mike
 

Gary335

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Thanks for the info! However,I was hoping someone might know more specifically which agencies are using these freqs. I had a pretty good idea thta some were police and some were ANG, just would like to know specifically what agency I'm hearing on some of them.
 

ka3jjz

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The 800 Mhz freqs belong to what is known as a trunking system. Baiscally put, these systems share the frequencies with numerous agencies, and are assigned specific user ids referred to as talkgroups. Your PRO-94 can hear the Baltimore county trunk, for example, and there are numerous police and fire groups that work for the county that use it. A little research using the databases here will bring those to light.
856.387(5) is used by the Anne Arundel county trunk system; while 860.2125 belongs to the Baltimore county trunk system.
To learn more about trunking, I would highly suggest you read the Trunking Basics and articles by Dan Veeneman of Monitoring Times; these articles are linked here This will serve you well, as trunking is used very heavily in Central Maryland

73s Mike
 
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Gary335

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Let me say it again: I've checked the database, and the frequencies listed were not there. I know all about trunking. Those frequencies in the 800 range were not assigned to any of Balto.Co's or City's trunked systems. That's why I asked for help in identifying them. If in fact those 800 freqencies do belong to either the county or city the RR database needs to be updated, because those freqs aren't listed for those respective systems.
 

Gary335

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Is it possible to hear things from other counties on a Radoshack Pro-94 with the original rubber ducky antenna? I'm in Balto. Co. and I hear stuff from both the city and county, which I would expect. But would it be possible to pick up transmissions from, say, Anne Arundel County? Or Harford County? If it is possible, I would imagine the conditions would have to be really good.....

Also, not far from where I live there are some radio towers....does living in close proximity to radio towers help with better reception?
 
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ka3jjz

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Your assumption about those 800 mhz freqs I mentioned is incorrect. The IDs are correct - the way those freqs are being listed, the last significant digit is being dropped for some reason. 856.387 is really 856.3875 and 860.212 is really 860.2125. Perhaps an incorrect tuning step is being used, or is that the way the PRO94 shows those frequencies (which is possible)?

Here is the Anne Arundel Trunk and the Baltimore County Trunk . Notice the list of frequencies.

Harford County's trunk is almost all digital (and therefore not receivable on a 94), and probably too far away on just a duckie. You are most definitely hearing at least 1 channel of the Anne Arundel system. Being close to radio towers is more often than not a problem; if the scanner can't handle the amount of signal that results, you could end up hearing nothing but garbage (intermod) or perhaps lose sensitivity on one or more bands (desense). Baltimore city's system is similarly digital, and also not audible on a 94. On both the Harford and Baltimore city systems, all you'll hear is noise.
Some of those other 450 mhz (and that one 151 mhz freq) are very likely businesses. The only way to identify them is to listen - record them, and hope that someone gives enough detail to id. Many, tho not all, use morse code IDs as well - get that, and you can use the FCC db to look up the user.
73s Mike
 
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Gary335

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Thanks for the info. I did mistakenly leave the last digit off of those 800mhz frequencies. I had a hunch I might have been hearing something from Anne Arundel. Now I'm sure I am. As for the 450mhz freqs and the 151mhz freq, I have heard some transmissions on those, but nothing that would identify them.

BTW, does anyone know if there are other types of antenna's that can be used with the 94? I've been thinking about going to Radio Shack to see what they have, but I don't want to make the trip if they don't have anyhting.
 

ka3jjz

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Yes indeed - they have a 800 mhz duckie that I understand really wakes radios up in that band. They also have a ground plane type antenna that is supposed to be very good, tho I'd hesitate to put it outdoors (kinda flimsy construction, as I understand it....). Fed with good quality coax and put into a nice high spot in an attic, it should wake that radio up without being TOO much for it, which can cause the problems I mentioned earlier. 73s Mike
 

maus92

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Fyi

I can receive AA County trunk in Baltimore City.... but cannot receive Baltimore City trunk south of BWI in AA County...

CA
Annapolis
 
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