I am struggling to pick up the mobile CHP units in my area and I don't ever recall having this issue decades ago. I understand the dispatcher can select different towers that can inhibit reception if the tower is a good distance from my location but even where I'm aware of a mobile unit is within 10 miles of my location I'm having zero luck. Yes, I have to correct frequency and CTCSS. I noticed the online scanner programs have a nice and clear reception compared to what I am picking up, if I pick up anything at all.
How can I get the same high quality reception of CHP frequencies as online software scanners?
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mmckenna
I ♥ Ø
Where are you located? Some areas have started using the statewide 700MHz trunked system.
If they are still on low band around you, the antenna really, really matters. Low band won't work well on a compromise antenna.
If they are still on low band around you, the antenna really, really matters. Low band won't work well on a compromise antenna.
bubbablitz
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The CHP patches the mobiles through the base frequencies in the Los Angeles area, so it sounds like a repeater. But they don’t do that all throughout the state, if that’s what you’re listening to on Broadcastify.
Santa Barbara.
I have multiple antennae. I am using different scanners and radios such a Yaesu VX-6R to pick up base or dispatch. Uniden BCT25AT programmed to all known frequencies used in Coastal Division (except the 700 MHz P25), Radtel 880G on dispatch, mobile, and uhf. I also have a couple of expandable antennas that I can expand up to 5 feet. I'm baffled why I can no longer pick up the mobile units.
I use a variety of software apps but I noticed similarities between them with the same channels. My guess is they are linking to Broadcastify.
mmckenna
I ♥ Ø
They sometimes reconfigure things, so maybe they've moved the transmit site.
If this are indoor/portable type antennas, that may not be enough. Low band likes 1/4 wave or larger antennas, outdoors and away from the common RF noisemakers that are probably in your home.
Telescoping antennas indoors on VHF-low is not an ideal set up. A tuned vertical, like the old Ringo Ranger, mounted outside would be the perfect antenna.
L3Harris [the defense contractor] sells a VHF-low band vertical that is easy to conceal from a HOA, is overbuilt, and designed for 30 to 90 MHz. It might be available as surplus property.
RF-398-01 is the model number and the NSN is 5985-01-620-4178
RF-398-01 is the model number and the NSN is 5985-01-620-4178
I programmed my Uniden BCD325P2 with mobile frequencies for Purple, Green, and Blue as well as all 4 extender frequencies that are P25. I finally got reception on the mobile with just the rubber duck antenna that came with the radio. No signals received on the 700 MHz P25 extenders. It looks like these are not currently being used but it's hard to say for sure until I do some dedicated monitoring. I have alert tones set loud so it lets me know if there's a hit
bubbablitz
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Those are for the vehicular extenders. Very low power. You’d have to be considerably close to the vehicle to hear anything. I haven’t lived in California for over 20 years, but back then, they used 154.905 Mhz for that purpose, and with a good outdoor antenna up high, you could usually pick it up within about a mile.
I think your difficulties are because you're misunderstanding how the system works. The 700 MHz 'extender' frequencies tie the officers' portable radio back to the mobile unit, and the mobile radio uplinks to the remote site on the regular 'M' lowband channel. The 700 MHz signal isn't expected to go very far and is very low power.
All the antenna help you've been offered was in the assumption you were trying to receive the lowband mobile uplink channel.
Even for hearing the lowband mobile uplink, unless you have an advantageous location, 10 miles is doing pretty good.
According to the database, Santa Barbara office on GRN/PUR/PUR2 and Coastal Division BLU are not repeated from mobile to base, so you'll need to listen to the Type "M" lowband (42 MHz) channels to hear the mobiles. Getting performance out of a lowband antenna is hard, but try a simple quarter-wave antenna with suitable ground-plane, cut/tuned for 42.6 MHz, up in the air, fed with LMR400 or something like it.
As others have mentioned, the 769 MHz extender channels are very low power and supposed to be good for only a couple hundred feet, by design. Are these really not encrypted?
As others have mentioned, the 769 MHz extender channels are very low power and supposed to be good for only a couple hundred feet, by design. Are these really not encrypted?
d119
Patch & Channels Clear...
I disagree. LMR400 is not ideal for lowband because it's overkill to begin with (RG-213/214 is fine for anything below 200MHz), and when LMR400 ages and oxidizes, the dissimilar metals will create noise on lowband, hence the reason nobody likes it for full-duplex use.
By "something like it", I meant in that category, as opposed to something like RG-58. LMR400 has become so popular that it's less than half the cost of 8, 213, 9913, etc., at least for new cable from an authorized distributor, not stuff that's been aging for a decade or two. I don't like the dissimilar metals sliding around either but in this case, where we're talking about a receiving antenna, do a good job sealing it and I think it's just fine.
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