ROCKY MOUNTAIN VHF SOCIETY - TECHNICAL INFORMATION
REPEATERS' STATUS (10/13/2012): 146.76 repeater system - transmitter and all receive sites operating normally 224.02 repeater system - operating normally 449.55 repeater - operating normally (repaired 11/09. See picture on right). 220/440 link - operating normally
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NØBP displaying defective legacy component from UHF transmitter. |
RMVHFS 146.76 REPEATER
The 146.16/146.76 MHz WØIA repeater is the designated emergency repeater for
The '76 2-meter amateur repeater is a sophisticated multi-site system based
on commercial 2-way radio equipment with some additional custom designed
hardware. The primary repeater is a Motorola MSR-2000 rated for 100 watts
continuous output. Multiple receive sites and a network of microwave and UHF
links provide for coverage from hand held radios throughout the plains and
mountain areas of
100 Hz sub-audio tone (PL, CG, or CTCSS) is required to access the receivers. See note below*.
The PRIMARY TRANSMIT SITE is located on Gunbarrel Hill in northeast
The antenna at Gunbarrel has 6-dB gain for transmit and receive and is set
for an omni-directional pattern. It is fed with low-loss semi-rigid feed
line. The roughly 300 watt ERP signal is adequate to provide usable
reception at virtually all locations on the plains and in the mountains of
Three additional receive sites are located within the County to provide for
coverage from hand-held 2-meter radios. A receiver in the hills above the town
of
The “courtesy beep” utilizes a system of tones to identify the receive site in use after the end of each received transmission as follows:
RECEIVE LOCATION |
BEEP |
PITCH |
TONE REQUIRED |
Gunbarrel |
Single beep |
Medium |
100 Hz (see Note below) |
|
Single beep |
Low |
100 Hz |
|
double beep |
high followed by medium |
100 Hz |
Table |
double beep |
high followed by low |
100 Hz |
The ID, DE WØIA/R T*, is transmitted via modulated CW every 5 minutes. (MCW ID's on the UHF links are transmitted every 9 minutes but are not retransmitted by the VHF repeater output.) The repeater time out timer (to prevent a permanent key up condition) is 2 minutes and is reset whenever the input signal is dropped long enough to allow the "courtesy beep" to be heard. The transmit hang time is 4 seconds. The transmitted 100 Hz tone is eliminated during the hang time in order to minimize squelch burst noise being received by the users who have activated their transceiver's tone decoding, and to facilitate cross-band mobile extender operation.
If no courtesy beep is transmitted, this is an indication that the voting system has been temporarily disabled and reception is only via the Gunbarrel local receiver. Likewise, if the "T" suffix is not heard on the ID then the Gunbarrel receiver is operating carrier squelch. See notes below for more details.
*NOTE REGARDING CTCSS TONES
Repeater Transmit:
The 146.76 repeater transmitter superimposes a 100 Hz sub audible (CTCSS, PL, or CG) tone on all transmissions. A tone decoder is not required by users to hear the transmit signal, but if used will eliminate local RF interference and squelch burst noise.
Repeater Receive:
Although the 146.76 repeater system remains an open repeater system for all users, a 100 Hz sub audible tone is required to access the system. This requirement is not intended to restrict access, but to minimize the effects of any RF interference generated near the multiple receive sites. This requirement can be temporarily removed by a control operator if necessary.
The repeater's transmit WØIA/R modulated tone identification includes an additional "dash" (Morse "T" for TONE) to indicate that the local Gunbarrel receiver is in the tone receive mode.
Temporary Suspension of tone requirement on Gunbarrel Receiver:
The requirement for tone access at the local Gunbarrel receive site can be
defeated by any user by their transmitting a DTMF (touch-tone)
"Ø". For the following approximately 5 minutes the main Gunbarrel
receiver will operate without the receive tone requirement. The 5 minute timer
is restarted whenever a Ø tone is received on any of the receivers. Note that in
order for this temporary defeat to occur, the Ø tone must be transmitted from a
station already implementing the 100 Hz subaudible tone. In addition, the tone
requirement can be disabled from the Gunbarrel receiver for any length of time
by the control operators.
RMVHFS 2-METER REPEATER SYSTEM |
RMVHFS 449.55/224.02 REPEATER SYSTEM
7903' MSL + tower 40.0722ºN, 105.3539ºW - UTM Zone 13, N 4435620, E 469822
Inputs at 222.42 and 444.55 MHz are usually repeated/translated simultaneously to 224.02 and 449.55 MHz. The 70 cm machine transmits a continuous 100 Hz tone and normally requires a 100 Hz (PL, CG, or CTCSS) tone to key up. A CTCSS tone decoder is not required by users to hear the 70 cm transmit signal, but if used will eliminate local RF interference and squelch burst noise. The 222.42 MHz input is carrier squelch. Both inputs are open to all users. Linking and other functions are controllable by the authorized control operators via a number of gateways, and some limited linking to the 2-meter repeater is possible for emergency situations.
These two repeaters (449.55 and 224.02 MHz ) are normally accessible through the EchoLink internet linking system. Call sign: W0IA-R. Node: 217336. For more information about EchoLink, follow this link: EchoLink.