||A new VE3STP repeater has been obtained through a JEPP grant and the Township of Greater Madawaska. Ownership of the repeater hardware remains with the township, and it is provided to us with the understanding that our ARES organization would assist the township with communications, if called upon, in the event of an emergency incident.
The repeater is a Motorola XPR8300 MOTOTRBO tranceiver, with an outboard matching 100 Watt RF amplifier.The repeater is powered by 115v AC, with a no-break 12 volt battery backup system to fall back on in event of an AC power failure. The amplifier is powered by its own Astron power supply, with battery backup. The battery could carry the repeater for 2 or 3 days, with controlled use. It is equipped with a modern external, commercial, GaAsFet receiving preamp which provides, along with the repeater’s already sensitive receiver, an amazing degree of low noise extended range reception.
The 100 watt amplifier provides us with coverage we have not enjoyed since the days of the original 90 Watt tube-type repeater.
The original 1972 Sinclair F150-4E duplexer (2 Tx and 2 Rx resonator cans) has been overhauled and re-installed, to give us a low 2 dB of insertion loss to the eight dipole vertically polarized co-linear array antenna. The antenna is mounted on a 68 ft self supporting Delhi tower whose base is embedded in a six foot cube of concrete. It is said that the antenna tends to favour the Ottawa-Carleton area but it has excellent general coverage.
Backup: The old and backup setup at VE3STP uses the Harris Alpha 2000 series two meter repeater.
Antenna: is an eight dipole vertically polarized co-linear array antenna. The antenna is mounted on a 150 ft self supporting tower shared with and owned by a wireless internet service provider. It’s sensitivity at 146.46 Mhz. is better than 0.50 μvolt for full quieting (20 db) with 0.3 μvolt for a 12 db SINAD.
The receiver is protected from the powerful transmitter signal by the duplexer whose role is to connect both receiver and transmitter to the antenna while isolating the receiver from the transmitter. This is achieved with an array of cavity resonators. The setup also offers some protection from cross and inter modulation products arising from strong signals from a commercial VHF radio communications tower not far away.The gain in this antenna gives us an effective radiated power of several hundred watts.
There is also a GE Master exec II which could be pressed into service quickly if required.
|Power Supply: The Motorola system runs directly from 115v AC, with a no-break battery backup of 2 – 12volt AGM lead-acid batteries, float charged by the repeater’s own power supplies. Hydro failure is signaled by a change in the courtesy beep, from the normal single tone beep, to a 2 tone beep, signifying “save the batteries, keep your transmissions short”.
The previous equipment, including the HARRIS backup repeater, and the packet repeater is powered from a Texpro 13.5V 45A power supply which is backed up by a bank of 100 ampere hour liquid Edison Nickel-Iron batteries.
Control: The repeater is controlled by a NHRC-4 repeater controller. It provides the identifier and various timing functions such as the tail length, identifier and talk out timer. The timers and other repeater functions may be set up or controlled remotely through the use of DTMF tones. In the event of abuse, the repeater may be shut down remotely by a control operator.
Time out: There is an over talk timer that temporarily shuts down the repeater if an extended talker goes on and on. Time out is signaled by a double beep.
These remote functions will soon be transferred to a separate multi channel telemetry and control system operating in another band.
Auto patch: There is no auto patch facility at VE3STP.
Linking: There is no linking between VE3STP and any other repeater. Echolink has recently been re-established.
IRLP: There is no IRLP capability.
Safety and Grounding: The tower grounding system is enormous and effective and has weathered nature’s assaults.
The Shack: The equipment is stored in a rugged vandal resistant building with intrusion signaling over the repeater and a local loud horn. A buried power service cable and antenna cable completes the facility.