F.C.C. terminology.....

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ka5lqj

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Dec 13, 2003
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Location
Near Lakeview, LA (Caddo Parish)
Hi,

I guess as you get older, you lose the ability to "wrap your mind @round things". I used to be IN the
2-way radio business back in the 60's, so this should be 'second nature' to me, but I seem to be having
a wee bit of trouble, now. I guess it's part of my "Maturing benefits", I suppose. Here's the "challanges".

I know the term FB2 is a "mobile relay" or "repeater". The mobile's transmit on one frequency and at
the "base" the transciever "hears" it and retransmits that signal thru a series of cavities, giving enough
'delay' as not to "swamp" the receiver and the signal goes out on the base's transmit frequency back to
the mobile radio who's reciever is tuned to the base transmit frequency. So far so good, right?

Well, seems I have trouble with the FB2C designation. It's a "repeater" but the "C" designates an 'interconnect'. Interconnect to what? Is this a reference to an mdt (mobile display terminal) -laptop?
or built-in unit in the transciever system.

Second, an FX1 is a sort of mobile relay that "hears" the mobile's transmission on it's same frequency
and re-transmitts it on the same frequency towards the base stations, mobile receiver's frequency, right?
So, isn't this essentially a point-2-point communications?

Now, to me, if the mobile is transmitting AND the Fx1 is transmitting, there should be an "interference" situation being set up, like 2 units transmitting at the same time and the difference in their frequencies produces that "growl" we hear....."hetrodyning", if you will. Am I making sense? HELP! I'm so confused.

Respectfully,
73,

Don/KA5LQJ

P.S. I'm sorry if I sound like an iD10t, but my brain just doesn't function as it used to...darn dementia!
 

loumaag

Silent Key - Aug 2014
Joined
Oct 20, 2002
Messages
12,935
Location
Katy, TX
You should always look here for your answers...well at least look in the Wiki first.

You will find a page that has all the FCC Station Class codes.

The interconnect means with a telephone. In other words a phone patch.

The FX is "Fixed" (nothing to do with repeaters) a FX1 is a control station.
 

ka5lqj

Member
Joined
Dec 13, 2003
Messages
427
Location
Near Lakeview, LA (Caddo Parish)
"Thanks, Lou. ;-)

Well,

I called myself lo^oking through the WiKi. I must have overlooked it. To prove my point about
my "brain", I just re-posted the same message, NOT remembering I had already posted it. I
was looking up frequencies and "forgot", DUHHHHH!

Many Thanks for the explaination. I never would have thought that would be the case. Here
Caddo 911 uses cell 'phones. There ARE two "telephone" channels in the 800 mhz "mix", but
most of them are used by the Water, Streets, etc depts. to call their wives and/or 'girlfriends'.
Sometimes the wives call the girlfriends thru the system and "it's ON!" LOL! It would make a
Marine Gunny DI blush! Needless to say, those two channels out of the 25 are blocked on my
Pro-95. :)

Well, it's supper time and "Madame" wants her computer back.

Blessings,
Watch the wx down there and stay safe.
73,

Don/KA5LQJ
 

KC0QNB

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Joined
Nov 4, 2007
Messages
730
Location
Gothenburg, NE
Actually the cavities are in part a real tight filter the takes out the frequency and reduces it to a low enough level so as not to interfere no delay it is just not "there".
The fb2c might be a repeater interconnected to another repeater, a remote control station or what ever.
As far as the mobile relay goes at least around here the state patrol uses a lowband frequency, but the troopers also carry a uhf radio, when they transmit their uhf hand held it does a crossband repeat to the low band frequency, and vice versa, don't know about you but carrying a handheld with a 6 inch antenna would be easier than carrying one with a 18" or longer antenna.
The fx2 could also be a store and forward system, it essentially hears and records the speech then when the first stage of teh communication is done the s&f system retransmits the speech through the mobile radio to the repeater (base station), and then it reverses, in this case a delay would be introduced,a single channel repeater if you will this is my guess. without knowing the system in question and what frequencies are involved it is the best I can do, NEXT!
 
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