OPP Historical

[LesWurk]

Was at the Bothwell car show today and there was a OPP Dodge Diplomat cruiser on display.
It has a GE radio inside and low band antenna on roof but shorter VHF or UHF antenna, also. Was this a accurate depiction of the radio system?
First pic attached is from internet and no antenna on cruiser. The next images are from the car show, sorry couldn't do better on the radio system inside without opening the doors.

 

[32dave]

42.060 MHz used for years. I use to hear Georgia state "skip" on it during the summer. I believe the short one is the repeater, no MDTs in '86

 

[LesWurk]

42.060 MHz used for years. I used to hear Georgia state "skip" on it during the summer. I believe the short one is the repeater no MDTs in '86

I'm not questioning the use of low band, however I might have not made it clear in one of the photos there is a VHF or UHF antenna on the car of this 80's vehicle. I spent most of my 80's life out of province, not sure of OPP stuff. First scanner about 1989 was RadioShack Pro-2021, which is still running on local fire dispatch but did OPP back in the early to late 90's

 

[32dave]

Short one is for UHF repeater.. (413 MHz) It's still in use until LMRN comes online. Some have switched to new 700 MHz. I tried to look it up in the ol' Haruteq scanner book but it's from '99. They went VHF in '98

 

[mikewazowski]

If it was a low band radio, then it probably had a PAC-RT which was on the UHF band. Somewhere around 458MHz I believe.

The 411MHz VRS's didn't come about until the NOR system was rolled out.

 

[mrweather]

My copy of Haruteq from 1993 has a few paragraphs dedicated to the OPP NOR system so it must have come online in the early 1990's? It mentions a mobile repeater frequency of 411.3125.

 

[mikewazowski]

My copy of Haruteq from 1993 has a few paragraphs dedicated to the OPP NOR system so it must have come online in the early 1990's? It mentions a mobile repeater frequency of 411.3125.

Test bed went live about '84 and I remember the old 6 District (Mount Forest) going online in '87 or so.

 

[mciupa]

Maybe these were used back then on that particular radio:
OPP
408.9125
410.8625
411.3125 MOBILE RPT.
411.5125
140.9700 SIM ONE
411.8125
414.1625
138.0125
138.3600
141.7650
141.7950
141.8400
151.7000
150.3350
141.8850
140.7900
141.0000
140.5500
413.5375 ORILLIA RPT.
143.2500
143.3100
TWRS: Ontario wide system- valid in any and all regions of Ontario
141.3900 107.2
141.1950 107.2
141.3000 107.2
141.4350 107.2
141.6900 107.2
143.6550 107.2
141.6300 107.2
141.4050 107.2
141.7050 107.2
141.4950 107.2
141.3600 107.2
141.7200 107.2
141.4500 107.2
141.5400 107.2
141.5550 107.2
141.6750 107.2
142.3650 107.2
142.6650 107.2
143.1000 107.2
143.1900 107.2
143.6400 107.2
142.8300 107.2
143.1600 107.2
Mobiles:- Ontario wide system- mobile input freq's to TWR channels
139.4700
139.1850
139.9500
139.1550
139.4550
139.0650
139.2600
139.0950
139.1100
139.2900
139.2150
139.4850
139.2000
139.3050
139.3200
139.3500
138.3450
138.6450
139.0800
139.1400
139.5000
139.3950
138.7500
COMMON 142.7700

I was listening to 42.06 Downsview and 41.96 Peterborough back in the 80's. Didn't we need filters on our scanners to block out the chirp on NOR or else you were held on frequency, after low band was decommissioned?

 

[mikewazowski]

I was listening to 42.06 Downsview and 41.96 Peterborough back in the 80's. Didn't we need filters on our scanners to block out the chirp on NOR or else you were held on frequency, after low band was decommissioned?

If memory serves me right:

42.060 base/42.220 mobile
41.960 base/42.020 mobile (London/Woodstock also used this pair)
42.000 aircraft

The NOR system used a ctcss of 107.2hz on voice so no filter was necessary. Without the ctcss , the cars would hear a momentary chirp of the MDC marker before the DOS kicked in. There were occasions when the repeaters would go faulty and the ctcss tone would stay on while the marker was being transmitted. As the system grew older, this happened more and more. Despite reports to the contrary, this was not an anti-scanner tone and the dispatchers could not control it.

 

[mrweather]

Test bed went live about '84 and I remember the old 6 District (Mount Forest) going online in '87 or so.

It must have been a gradual roll out because I know I was still listening to them on low-band until at least 1989 (at least in Windsor/Essex County).

Didn't we need filters on our scanners to block out the chirp on NOR or else you were held on frequency, after low band was decommissioned?

If your scanner had PL decode your could set it to 107.2 Hz and block out the repeating chirp while allowing voice transmissions to pass through. I do recall the repeated audio volume was quite low.

 

[gary123]

OPP used mocom 70 and pac-rt. Also had lots of GE masters. All 100w. Low band. This transitioned to the VHF synotrs later.

 

[mrweather]

I thought they used GE Rangrs in the cars?

 

[hypersight]

If it was a low band radio, then it probably had a PAC-RT which was on the UHF band. Somewhere around 458MHz I believe.

The 411MHz VRS's didn't come about until the NOR system was rolled out.

I believe it was 458.8625 MHz. It's been a loooong time though!

 

[32dave]

OPP used mocom 70 and pac-rt. Also had lots of GE masters. All 100w. Low band. This transitioned to the VHF synotrs later.

Totally forgot about that system

 

[gary123]

Yes, the PAC-RT was on 458.8625. There was a lot of equipment variation in the early days as anything capable of operating the 42 MHz freq. was purchased as the fleet expanded. The advent of the VHF system eliminated competitor radio hardware because of the unique radio system design chosen.

 

[exkalibur]

I thought they used GE Rangrs in the cars?

EMS used these extensively throughout the Province.

It must have been a gradual roll out because I know I was still listening to them on low-band until at least 1989 (at least in Windsor/Essex County).


If your scanner had PL decode your could set it to 107.2 Hz and block out the repeating chirp while allowing voice transmissions to pass through. I do recall the repeated audio volume was quite low.

The repeated audio was likely just cross talk. When operating in NOR mode, the mobile's audio was not retransmitted - you'd only hear the PCC on the tower. The system would operate in full repeater mode if a Line Patch was used (two units to talk to each other) or a TAC was setup (site operated as a regular repeater more or less). More often than not, some of the mobile's audio would bleed through but was extremely low.

 

[mrweather]

EMS used these extensively throughout the Province.

When did EMS use low-band?

 

[LesWurk]

When did EMS use low-band?

From 1971 by license plate (both pictures taken nearly same time), the ambulance service was often run by funeral homes. In this picture, both cars show Low Band antennas

 

[lenk911]

When I worked for Minnesota Department of Highways in the early 1970's. we cross monitored our Highway Patrol's 42 Mhz station at Grand Marais, MN with OPP's 42 Mhz station at Thunder Bay.
Our Duluth dispatch center would transmit a beep tone on our channel to open the cross connect circuit to their dispatch center. The FCC really had heart burn. It took almost an act of both US and Canadian government's state departments to allow cross border communications.

 

[exkalibur]

When did EMS use low-band?

Sorry, my comment wasn't low band specific. EMS used Rangr mobiles in VHF hi-band for ages.