Question For Anyone Familiar With San Jose, CA

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mistertee

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San Jose, CA
After many years away from scanning I recently took up the hobby again. Years ago I lived in the Mountain View area which is about 15 miles North of San Jose. As I recall, I used to get good-to-excellent results scanning the SJ PD primary frequencies even with an indoor antenna. I now live within 3 or 4 miles of San Jose's "Communications Hill", yet I only receive a few of these channels with decent signal strength/listening quality. 6,7,8 and 1 are OK but all the others are either weak or non-receivable. San Jose Fire primary is also weak but listenable. I'm using a Diamond SRH-789 antenna which I adjust as needed to suit the range I'm monitoring. Just wondering if anyone has any idea why reception is so spotty now.
 

bezking

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Hi mistertee,

As you'll see I've moved your post to the California Radio Discussion Forum. In the future, please post location-specific questions in the respective State forum - you are more likely to receive a correct response from someone who is local to your situation, and it helps to cut down on clutter in some of the other forums we have...

Thanks and welcome to RadioReference!
 

kmh603

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Hello could you be a little more specific on your post? What freqs are you trying to listen too. Maybe you are listening to the input freq and not the output? Does you scanner have the correct "PL" tone in it and also you might have "ATT" enabled which would cause you not to recieve? What type of scanner do you have and what type of scanner software are you using? SJFD has switched freqs, so you might be monitoring the output?? You might also have lockout those SJPD channels?

Thanks

KMH603
 

stingray327

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Jan 29, 2008
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San Francisco, California bay area
After many years away from scanning I recently took up the hobby again. Years ago I lived in the Mountain View area which is about 15 miles North of San Jose. As I recall, I used to get good-to-excellent results scanning the SJ PD primary frequencies even with an indoor antenna. I now live within 3 or 4 miles of San Jose's "Communications Hill", yet I only receive a few of these channels with decent signal strength/listening quality. 6,7,8 and 1 are OK but all the others are either weak or non-receivable. San Jose Fire primary is also weak but listenable. I'm using a Diamond SRH-789 antenna which I adjust as needed to suit the range I'm monitoring. Just wondering if anyone has any idea why reception is so spotty now.

It's too bad Glen retired in San Carlos (Scanners Unlimited) he would have the answers for you.
 

WA1ATA

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Jun 18, 2010
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Fairhaven MA / San Jose CA / Kihei HI
Perhaps "communications hill" is between you and the transmitters for the channels you don't receive well.

Looking at one of the licenses for the PD freqs, you can see that there are several transmitter locations. Your reception undoubtably depends upon which transmitter site is used.

see FCC Callsign KMA359 Details

SJ seems to keep the same tx sites for a given channel, unlike the CHP which may change several times a day. Unfortunately, one of the weaker signal is the SJPD channel 7, which is for the area closest to my monitoring location in San Jose. I suspect that for Chan 7 they use Mt Chual, a bit to the south of Mt Umunhum.
 

kmh603

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SJPD and SJFD all simulcast their dispatch channels. Which means when they transmit on a dispatch channel all dispatches go out to all the transmitter sites. Only SJFD Command 11 is on Mt. Chua that is why that channel is received so good. Tac Channels and Car to Car or on Fireground communications are not simulcast so you may not receive those channels as good.
 

WA1ATA

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Fairhaven MA / San Jose CA / Kihei HI
SJPD and SJFD all simulcast their dispatch channels. Which means when they transmit on a dispatch channel all dispatches go out to all the transmitter sites.
Are you sure the SJPD simulcasts from all transmitter sites?

Both the original poster and I have seen large variations in the signal level between the various 460.xxx SJPD freqs.

To me, the differences in signal levels indicate that they probably have selected a transmitter site for each channel that gives good coverage into the area served by that particular channel.
 

stingray327

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San Francisco, California bay area
After many years away from scanning I recently took up the hobby again. Years ago I lived in the Mountain View area which is about 15 miles North of San Jose. As I recall, I used to get good-to-excellent results scanning the SJ PD primary frequencies even with an indoor antenna. I now live within 3 or 4 miles of San Jose's "Communications Hill", yet I only receive a few of these channels with decent signal strength/listening quality. 6,7,8 and 1 are OK but all the others are either weak or non-receivable. San Jose Fire primary is also weak but listenable. I'm using a Diamond SRH-789 antenna which I adjust as needed to suit the range I'm monitoring. Just wondering if anyone has any idea why reception is so spotty now.

A scant antenna or discontinued Channel Master antenna are tops in performance however they are outdoor antennas and you probably don't need that because of your location.
 

dxradio2003

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Jan 31, 2004
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Sjpd

Hi,

I have been scanning since 1970 and in particular, SJPD. Your assessment is correct. I don't know the technical aspects of their transmitting sites, etc., however, I too have noticed the same poor reception on some channels.

I notice that the reception seems to be region specifc and I suspect that they use specific transmitters for specific districts. That's why SJ-3 seems to come in best in NE San Jose and not so well in South SJ.

Remember, that Communications Hill is primarily limited to Santa Clara County Communications. SJPD has no dispatchers at this site and probably not many (if any) actual transmitters at this site.

You can always check the FCC database for actual location sites I believe. You will likely notice the strongest channels appear to be SJ-8, SJ-9, SJ-11.

At some point, they should eventually migrate to the new 700 Mhz band, however, I don't know the projected date/year.

Hope this helps.

---dxradio
 

stingray327

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San Francisco, California bay area
Hi,

I have been scanning since 1970 and in particular, SJPD. Your assessment is correct. I don't know the technical aspects of their transmitting sites, etc., however, I too have noticed the same poor reception on some channels.

I notice that the reception seems to be region specifc and I suspect that they use specific transmitters for specific districts. That's why SJ-3 seems to come in best in NE San Jose and not so well in South SJ.

Remember, that Communications Hill is primarily limited to Santa Clara County Communications. SJPD has no dispatchers at this site and probably not many (if any) actual transmitters at this site.

You can always check the FCC database for actual location sites I believe. You will likely notice the strongest channels appear to be SJ-8, SJ-9, SJ-11.

At some point, they should eventually migrate to the new 700 Mhz band, however, I don't know the projected date/year.

Hope this helps.

---dxradio

I'll have to check to see if my scanner even covers the 700 mhz band. Scanning goes a ways back for me too. I started out with a Lafayette Multi-band radio in 1973 then moved on to a Regency 10 channel scanner that required crystals in those days.
 

kmh603

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You are Correct. SJPD does simulcast dispatch, but they do it specific to the SJPD beat. So eastside simulcast from transmitters that specific to the east side, whereas, SJFD does city wide. On those tac channels, SJPD 8,9 11 and such, those are city wide tacs, that is why those come in better. As far as the public saftety going to 700 mhz, I do not see that coming any time soon as Motorola gave a bit of 25 million or so to convert and as city budgets go, I do not see that happening anytime soon until the Feds give up some money for cities to convert.
 

MonitorMike

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Jul 6, 2011
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Back when I got my first scanner in 1976, I noticed the same thing. At the time, I lived in the Almaden Valley, so SJPD F4 was very strong, with fair reception on F1, spotty on F3, and horrible on F2. That scanner didn't have good RF sensitivity, though. I did try some mobile scanning, and, yes, SJPD is set up for regional reception.
 

UncleFester78

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San Jose, CA
I'll chime in here as well... I live off Oakland and Brokaw Rd. I can pick up SJPD 1, 3, 5, 6 and 9 perfectly. SJPD 2 and 4 is scratchy, but clear with my vehicle mounted antenna. SJPD 7 & 8 are very hard to pick up.

I've noticed the same bad reception with SJFD Command 13. I guess because after the rebanding it's the "SOUTH" command channel.
 

trooperdude

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SFO Bay Area and Las Vegas NV
Couple of factors:

SJPD moved to narrow band transmissions which doesn't provide the same
coverage (especially if you listen to it wide-band on a scanner).

When they did the switch, the new antennas have a LOT more down-tilt on
the antennas. More RF saturation in the district, less at the fringe reception areas.

Gone are the days of high-level, high power sites. Frequency coordinators no longer allow it so you get easier frequency re-use outside of the primary area.
 

Oyabun

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Silicon Valley
Question For Anyone Familiar With San Jose,Ca.

Hhmmm... I live in South San Jose. Almaden & Capital Exp. I have
7 hand held scanners. All using the antennas that they came with.
With the exception of a Watson W-881 I've had little to no issues with reception.
Listening to SJPD,CHP,SJFD,SCCF,SCCSO...The scanners I'm using are
a Uniden BC100XLT,RS/PRO-24,RS/PRO-51,
RS/PRO-97,AOR-2700,RS/PRO-107,RS/PRO-107,
RS/PRO-106,& GRE/PSR-800. All have great reception with the exception of the Uniden BC100XLT not receiving 42.000-45.000mhz.(CHP) which it used to receive.
 

trooperdude

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probably because you are in the primary saturation corridor.

Here on the west side against the hills, sjpd 4 is extremely fringe reception on everything but my Astro Saber. And even that's iffy if i move around in the house.

The system is working as designed and keeping most of the signal where it's supposed to be. Within the service area.
 
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