Florida: School officers say a majority of their radios don't work inside schools

[KS4VT]

Palm Beach County school district police offices say the life line they use to keep your kids safe at school are more like crossed lines.

School officers say a majority of their radios don't work inside schools | school, say, police - Top Story - CBS Channel 12 News

As a side note, these officers are not on the County TRS and prefer to utilize their own 800 MHz conventional radio system.

[MTS2000des]

Originally Posted by KS4VT

Palm Beach County school district police offices say the life line they use to keep your kids safe at school are more like crossed lines.

School officers say a majority of their radios don't work inside schools | school, say, police - Top Story - CBS Channel 12 News

As a side note, these officers are not on the County TRS and prefer to utilize their own 800 MHz conventional radio system.

Mark here in Cobb county, GA our BOE police (which are school system not CCDPS employees) still carry two radios, one on their UHF conventional analog system and one on the CCDPS Astro 25 system. In building coverage on the new DTRS is slightly better than it was on the Smartnet analog, but not much. The high cost of Astro 25 subscriber units is another reason the BOE still stays on UHF conventional. They have 6 repeaters on two high sites (one of them we have a 440 ham repeater co-located on) and they get better in-building penetration than the 800 radios do.

I did alot of work with CCBOE at the radio shop I used to work for back in the late 90's when we had their maintenance contract. At the time, the county was on their Smartnet system, and I did many tests using an MTS2000 on the system side by side with a Kenwood TK-350G inside all the high schools, and about half the middle schools in the system. Our two other techs ran around to about 3/4 of all the elementary schools, from this test the 800 radios did not work in about 60 percent of the structures. The UHF radios, OTOH, had around 85-90 percent usable coverage. The decision was made by the BOE to remain on 450MHz and not put all the BOE operations on 800MHz. The cost of the radios was the other factor.

I know your system in PBC probably has much better coverage than what we deal with here, but who maintains the radios on their system? Would it be cost effective for the school board to join your TRS as subscribers versus building out their inadequate 800 conventional system? Are there other users (transportation, maintenance, administration) sharing those channels or just school police? Just curious.

[b7spectra]

I thought the BOE police are actually CCSO assigned?

[MTS2000des]

Nope Mike, the Cobb BOE Police work for the Cobb County Board of Education, and are entirely separate entity from the Cobb County Department of Public Safety. Their paychecks come from Glover Street not Cherokee St!
The SO does work with them on drug sweeps, football games, etc. But the BOE PD are the ones who provide year round building security, and campus law enforcement. They are the 6900 units when you hear them on the DTRS on various PCT's. They use to refer to CCBOE dispatch (which does have a GCIC terminal and agency ID) as "800" but now as "6900".

If you want to see their report forms, check this out:

http://www.cobbk12.org/centraloffice...PENDIX%20A.pdf

The CC BOE police DO NOT have crossing guards, ironically. CCPD does that, part of the "adjunct services" unit.

Sometime in the late 1990's BOE formed their own "department of public safety" and changed their patch from "Education Safety" to "Department of Public Safety". If you remember, they were all POST but told by the late Chief Robert Peel to disarm and keep their guns in lock boxes in their offices. That went away after some incident at Sprayberry HS IIRC where some heavily armed people were found on campus packing serious heat.

[KS4VT]

Originally Posted by MTS2000des

I know your system in PBC probably has much better coverage than what we deal with here, but who maintains the radios on their system? Would it be cost effective for the school board to join your TRS as subscribers versus building out their inadequate 800 conventional system? Are there other users (transportation, maintenance, administration) sharing those channels or just school police? Just curious.

They have their own radio shop and maintain their own radios. They keep telling me I'm too expensive, but you get what you pay for.

As far as users, SB maintenance and buses are on UHF LTR. I would not want their traffic on the TRS.

Mark

[DaveNF2G]

It is a fundamental fact of radio life that under most circumstances radios inside of a building cannot easily communicate with radios outside of the building. Customers should be told that indoor coverage with an outdoor radio system requires additional infrastructure - passive repeaters, amplifiers, microcells, leaky coax, or something that will carry signals past the walls.

[N_Jay]

I think people are over simplifying the inside vs. outside discussion.

Radio systems are typically designed with some amount of signal margin, and even if designed only for "on-street" use, the system will have various amounts of margin depend on where you are relative the towers and other factors.

That margin may be 6 to 40 db across a geographic area.

Additionally, the loss in a building varies greatly depending on the structure of the building, and the location inside. That loss is typically assumed to be between 4 dB and 60 dB depending on many factors.

Band is one factor, but tower location is far more critical.

[gcr33]

With the Palm Beach Co. trunked radio system they would have coverage in the schools. The school board radio system needs big time help or a switch to the county system.

[MTS2000des]

Originally Posted by N_Jay

I think people are over simplifying the inside vs. outside discussion.

Radio systems are typically designed with some amount of signal margin, and even if designed only for "on-street" use, the system will have various amounts of margin depend on where you are relative the towers and other factors.

That margin may be 6 to 40 db across a geographic area.

Additionally, the loss in a building varies greatly depending on the structure of the building, and the location inside. That loss is typically assumed to be between 4 dB and 60 dB depending on many factors.

Band is one factor, but tower location is far more critical.

Problem is getting customers to pay for the needed coverage. They often hear "90 percent mobile coverage" and stop there, when on hip portable coverage is significantly less.

Most of our schools (especially the elementary and older high schools) were built in the 1950's-1970's and are 6" steel reinforced concrete. No RF from a distant site penetrates that well and talking out with a 3-4 watt portable is even more challenging. The 2 watt VHF "dot" radios the elementary schools purchased barely make it from one side of the campus to the other.