sopranosno1
Member
- Joined
- Dec 19, 2002
- Messages
- 590
the fcc has seventy seven 700 mhz frequencies pending for the state of ohio....
MARCS-IP ("New MARCS") Site and Talkgroup Discussion
Not quite. That application has nine actual FB2 trunked (output) frequencies. If you take a close look, you'll see:
9 ADDED frequencies (the ones I listed)
2 DELETED frequencies (which I omitted)
7 Locations (encompassing 5 simiulcast locations, the mobile "location" and the FX "location").
(9 + 2) * 7 = 77.
As far as people wanting to program the trunked system, they would only be programming the 9 FB2 frequencies.
Of course, this assumes that the FB2 frequencies listed in this application are actually the ones used on the simulcast system.
Mike
sopranosno1
Member
- Joined
- Dec 19, 2002
- Messages
- 590
you are right. thanks for the correction. question, i found two web pages with 700 mhz public safety
freqs. one at wiki radioreference and jts203.com. problem is there is a difference. one has 769 to 775. the other 764-766 and 773-776. why the difference?
freqs. one at wiki radioreference and jts203.com. problem is there is a difference. one has 769 to 775. the other 764-766 and 773-776. why the difference?
will parma merge their TRS into this one once its done?
budevans
Member
Where do I begin!!!
Politics (ego's), Finances (costs) and last but not least Vendor P25 compliancy issues (Moto P25 vs Ma/Com P25). Everything will work just fine as long as the other guy will match our version of compliance.
They're all compliant and networkable at the basic levels; it's the vendor-specific advanced features that aren't compatible, but those have no effect on the ability of the systems to network with each other, or the ability of a Motorola radio to operate on P25 systems from EFJ, Harris (formerly M/A-Com), even Kenwood or Relm.
I wish I could answer that, bu ti plead clueless. Given the lack of operations around here in the 700 mhz band (except for perhaps OSP MREs), I haven't really schooled myself on the bandplans and such. I'm not sure who to believe
Mike
Here's the current info:
The 700 MHz narrowband public safety band is:
769-775 MHz (Base/Repeater/Mobile use)
799-805 MHz (Mobile only)
The 700 MHz broadband data public safety band (aka D Block) is:
763-768 (Base transmit)
793-798 (Mobile transmit)
There is a 1 MHz guard band between the narrowband & broadband allocations.
Reference: 47CFR90.531
The site listing the 764-766 and 773-776 MHz bands is out of date, those were part of the 700 MHz band plan prior to the FCC attempted auction of the D block for a public/private data network, reference FR 58651, 1998
Does this mean that the current Lake County TRS, will be upgraded to ASTRO 25 platform 7.x?
73s
Ron
Yes, Lake County will eventually have a 7.X simulcast cell attached to the zone controller/master site already installed at the Lake County EOC. The ZC at Lake County will have interzone links to the states ZC's in Columbus so roaming between Lake & MARCS would be a possibility.
Right now Lake County is using a SmartX converter to connect the existing 7E26 system to the 7.X master site & MCC7500 consoles, so they are already making progress towards a full Astro 25 system.
The 700 MHz Cuyahoga MARCS system & the future Lake County system will use linear simulcast modulation (LSM). Search the forums for some of the difficulties experienced by listeners in Lucas County and elsewhere decoding these systems.
budevans
Member
So, the license has been granted and build out is to commence. I'd like to setup my scanner to start monitoring and I have a couple of questions.
1st: Do I set my scanner (GRE 500) for Moto 800/900 or P25 Auto?
2nd: Does the above mentioned Linear Simulcast Modulation pose a problem for the GRE 500?
Note: I currently receive the Parma P25 system without issue. Parma P25 is listed as a three site simulcast system. I don't know if Parma is using LSM.
Any suggestions, would be appreciated.
P25 mode
I'm sure others with more experience scanning LSM systems will offer their experiences with the different models.
Any problems would be related to your location & the difference in field strength from multiple sites. Those in overlap areas, where two or more transmitters are within about 10 db of each other, may experience problems and those located where a single site dominates may notice no problem at all.
The recommended cure is to use a directional antenna to get one site stronger that all the others or to null out the offending site.
I don't know if the Harris supplied Parma system uses LSM or something else.
budevans
Member
kf8yk,
Thanks for the quick reply. I've setup the TSYS object and set it for P25 Auto.
Now I'll just sit back, monitor and keep an eye on this thread.
Thanks for the quick reply. I've setup the TSYS object and set it for P25 Auto.
Now I'll just sit back, monitor and keep an eye on this thread.
eorange
♦Insane Asylum Premium Member♦
The Lat/Lon of Location #1 is the exact location of the "pole" I referenced in post #7. This is less than 2 miles from my house, so I will be monitoring those frequencies.
So maybe I'll notice a new antenna for 700 MHz going up...? What would that look like?
Like an 800 MHz antenna (collinear), or a cell tower antenna (panel). They're pretty much indistinguishable.
eorange
♦Insane Asylum Premium Member♦
Makes sense to me. Both of those antenna types are already up there, I think (existing, from years ago, along with a discone). Not sure I'd even notice if something new went up. Regardless, time to start monitoring!
budevans
Member
Heard (digital) traffic on 769.50625 both yesterday and today. Todays traffic (2:10 p.m.), users were reporting to a location for a meeting. Yesterdays traffic (5:00 p.m.) was a mobile transmission "on i271 approaching i480".
Has anyone else picked up traffic on any of the MARCS Cuyahoga County 700 Mhz frequencies?
Has anyone else picked up traffic on any of the MARCS Cuyahoga County 700 Mhz frequencies?
budevans
Member
More traffic on 769.50625. User in the Chagrin Valley with a portable called in reporting "Full quieting on reception". Other parties commented that three of the five towers are operational. The tower at the Cleveland Justice Center to be up shortly. The last site is having T1 issues which are being worked on.
FYI, I have two setups for these frequencies.
First, is Conventional, squelch mode set to none. Which is where I am hearing the traffic.
Second is a TSYS P25 setup, which I haven't received any traffic. But I do see 5 bars signal strength on TSYS P25, just no traffic.
FYI, I have two setups for these frequencies.
First, is Conventional, squelch mode set to none. Which is where I am hearing the traffic.
Second is a TSYS P25 setup, which I haven't received any traffic. But I do see 5 bars signal strength on TSYS P25, just no traffic.
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budevans
Member
Testing ongoing from MARCS unit 62 and 4571 to MARCS Radio Service in Columbus. 62 is moving a console and expects it be up in three hours (6:00 p.m. est).
One other note, have received conventional traffic on a second frequency 769.75625.
One other note, have received conventional traffic on a second frequency 769.75625.