Since the Metropolitan District Commission sponsored the W.P.A. Radio Survey Project, the engineers have been engaged in planning and creating an efficient two- way police radio system. The experimentation and research work handled by these qualified men is developing a modern communications system for the territory under the jurisdiction of the commission that will be comparable to any in the country. It is also felt, that the system will greatly increase the effectiveness of the Commission's services which have for more than forty years been rendered to the forty-three communities of over two million persons. Protection of the health and safety of the inhabitants of the municipalities which comprise the Boston Metropolitan areas will be increased through the development and maintenance of this most modern communications network. At the end of the year 1937 the results of the Police Radio Survey is evidenced by having in actual operation a crystal controlled high-powered transmitter, licensed by the Federal Communications Commission for a maximum power output of 500 watts; a specially constructed "J" type antenna, employed with a newly developed feeder cable arrangement; and three cars equipped to both receive and transmit messages and tests. When not actually engaged in field work these three radio equipped cars are available for routine police duty. During the year 1937, there has been added to this equipment two portable radio sets for use in such emergencies or exigencies as floods, fires, boat portage, etc. This equipment, with several smaller units are constructed to operate efficiently on the same frequency as the transmitter and receiver at the main control room located at 20 Somerset Street in Boston.
To fulfill the purpose of the Radio Survey Project, namely to develop a communi- cations system sufficiently proper to meet the needs of the Commission, it was necessary to conduct tests both from the cars to headquarters, and from headquarters to the cars, over roads and paths that are police patrolled, and accessible by auto- mobile. These tests were conducted throughout the year, and during both the days and nights, with all qualities of reception at every location recorded by proper registering meters. The following list of field readings were made this year as a basis for proposed field pick-up points (receiving stations). 3,766 Readings made using a location in each division as a pick-up point. 1,058 Readings made from mobile units to M.D.C. Headquarters. 250 Readings made from M.D.C. Headquarters to mobile units. 562 Readings made from mobile units to permanent location in Blue Hills Division. 625 Comparative readings from Headquarters to mobile units, M.D.C. No. 197 and M.D.C. No. 198, for equipment tests. 6,261 Total
In order to cover the entire Metropolitan District, it is necessary to have the antenna of the main transmitter erected well in the clear of any surrounding objects. When the antenna at 20 Somerset Street was first built, every effort was made to fulfill this condition, but during the year the Suffolk County Court House has been constructed. This new building is much higher than the top of the Head- quarters antenna. Tests have indicated that this structure is acting as a shield, greatly reducing the amount of signal to be received in Revere, Winthrop and Nantasket. The mobile radio transmitters used in the police cars are necessarily limited as to power output and antenna height. These limitations make it impossible for cars operating in the outlying areas to communicate directly with Headquarters. To overcome this condition, it is necessary to locate receiving stations at selected points in the territory to be served. The field strength tests conducted by the Survey have determined that with receiving stations at Lawrence Observatory in the Middlesex Fells and at Blue Hill, it will be possible to hear the cars at any point in the district. A "J" antenna was installed on the roof of the Harvard Observatory at Blue Hill to operate a receiver located in the building. This receiver feeds into a direct wire running to 20 Somerset Street, Boston. At the Boston end a line P.D. 48 23 amplifier built by the Project is used to operate a loud speaker or other equipment. This circuit operates unattended on a 24-hour a day basis and is ready to be used as a part of the permanent installation. At the Lawrence Observatory an antenna similar to the Blue Hill installation has been erected. During 1938 this circuit will be completed by the addition of a receiver and telephone line to Boston.
All construction and testing work on the Radio Project has been accomplished by W.P.A. labor and through W.P.A. funds. Material and equipment installed has been purchased by the Commission.
39 Megahertz System
39.580 F1Output 39.660 F2 Input
Original set up was semi-duplex. Headquarters talked out on F1 and mobile units (cruisers, boats, motorcycles and handheld talked back on 39.66.
MDC Police - 1 Repeater/Mobile Relay on Great Blue Hill, Milton, MA provided radio coverage for Greater Boston and beyond. Ch.1) 39.580 R 110.9 Hz Boston/Canton w/ 39.660 input Ch.2) 39.660 S 110.9 Hz Quabbin Ch.3) 39.720 S 110.9 Hz TOPS and Det's Ch.4) 39.600 S 110.9 Hz Marine Unit Ch.5) 39.700 S 110.9 Hz Car to Car Ch.?) 39.200 S 110.9 Hz Spare
With the introduction of scanning receivers/scanner radios, monitoring multiple police radio frequencies at once became easier. Picutured is a working 10 channel Regency Monitor Radio from the mid 1970's. Acquire the frequency crystals, and you were good to go to listen to the Metropolitan Police at work! (Photo courtesy of Brian Kerins, Jr. Used with permission.)
Base stations and radio towers located in: Barre Boston Clinton Framingham Hull Medford Milton New Salem Pelham Petersham Southboro
Portables/Handheld Radios
453.25 KCC81 453.45 KCC82 453.75 KCC80
158.970 MHz Intercity
158.970 KCA992 Intercity
195x: "Intercity" radio channel installed for direct radio comm with Div. of State Police, Registry of Motor Vehicles Police, Boston Police Department and several cities and towns. Base only communications.
B.A.P.E.R.N.
Proposed but never funded five UHF T Band channel pairs. One of several studies and proposals, the Greater Boston Police Council in 1972 did a study of the MDC's communication system and made recommendations to the department as well as the Commonwealth. Additionally a study was conducted of the Massachusetts State Police and their communications needs.
Repeaters located in Arlington, Boston, Canton provided portable radio coverage generally out to the 128 Belt and mobile coverage out to Interstate 495. Repeaters in Princeton and Ware, MA provided coverage for Quabbin Reservoir and Wachusett Reservoir patrol areas.