Has something changed on Fairfax County FD dispatch. Checked frequencies etc but I cannot receive them.
Any input appreciated.This is the P25 system.
Any input appreciated.This is the P25 system.
Fairfax County FD reception
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cpetraglia
Member
Talk Group 1519 on the P25 system. Active constantly.
I commute to DC from Spotsylvania every day so I dont normally listen to any Fairfax FD or PD. Since I do come up to Fairfax at times for work I thought I would QC my BCD396T to make sure I have current freqs and TGIDs. (I did not) So after updating freqs and new TGIDs to what is currently listed in the RadioRef database for both FD and PD I don't hear a damn thing. Control channel is coming at about 4 bars but often get the "finding control channel" message while on 395/95 around Springfield/Lorton. I get MWAA just fine.
Am I missing something? Any special scanner setting I need to do. (I'm not a scanner newbie so its a bit frustrating).
Thanks in advance.
Am I missing something? Any special scanner setting I need to do. (I'm not a scanner newbie so its a bit frustrating).
Thanks in advance.
freqhopping
Member
LSM Linear Simulcast Modulation is the most likely reason.
This is less of an issue with the newest Unidens.
I am using a BCD369XT. I get Prince William and DCFD just fine. Can the 369 receive fairfax if properly configured?
Can you confirm which scanner you are using? Your earlier post said BCD396T. Now you say BCD369XT. You have your numbers transposed (should be 396). But it could make a difference whether you are using an older BCD396T or a newer BCD396XT.
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Fairfax FD is a simulcast system, which means that multiple transmitter sites transmit the same signal, and they interfere with one another in most scanners, particularly if you are equidistant from several transmitters.
I live in the Rockville area, and my Radio Shack/GRE scanners show three bars but can't decode the transmissions. But they do a better job when driving through Fairfax County. My Uniden 436 does an even better job but still it's not reliable.
I live in the Rockville area, and my Radio Shack/GRE scanners show three bars but can't decode the transmissions. But they do a better job when driving through Fairfax County. My Uniden 436 does an even better job but still it's not reliable.
Sorry about that. I have a BCD396XT.
OK So is there a work-around or something that I can do? Some people are apparently able to make it work.
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I think the most commonly recommended workaround for simulcast reception problems is applicable to scanners in a static location and involves using a directional antenna to get a strong signal from one tower while limiting signals from other towers. If you are mobile, I'm not sure you have good options.
Have you tried monitoring Stafford County? Stafford has a simulcast system, and I was wondering if there was any difference for you between Stafford and Fairfax.
I am not located in the vicinity of Fairfax and have not tried to monitor Fairfax since they switched to the P25 system, so there is a limit to how much I can help you. I just know many people have posted on here saying that Fairfax P25 has been a challenge for them. Searching the forum on "Fairfax" and/or "Simulcast" would probably show you what others have been saying.
One other thing I thought of - do you have the latest firmware for your BCD396XT? I don't own one of those, but I think there was a firmware update that attempted to improve simulcast reception.
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In line filter is the only fix. Saving up to buy an efjohnson viking vp900. Its audio codec is way more advanced then moto's on the ambe+2 platform. EFJohnson Viking VP600 Portable Radio vs. Motorola XTS and APX - YouTube
AND ITS VHF, UHF(380.0 AND UP), 700 AND 800 MHZ
AND ITS VHF, UHF(380.0 AND UP), 700 AND 800 MHZ
ANOTHER thing causing reception issues are the jumping of voice frequencies mid traffic or 1-2 seconds after a unit keys up. If you watch fairfax's system decoded, you will will notice what im saying. Loudoun county's does it as well.
cpetraglia
Member
And once you get this radio, how will you program it to a local P-25 system?
I am confused.
Chuck
I am confused.
Chuck
With programming software and passive monitoring technique.
One fix is to conventionally monitor the talk groups. Bypass the control all together. Audio is 5 by 5 that way.
Codec2 fixed my problems with reception. DSP is set as low as possible on my psr800 and all forms of attenuation are off. Gain set to 0. Can't wait to get all the hardware possible to use codec2 to its full potential.
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