Remote Controllable Antenna Monitor
The Model CMR is a state of the art instrument with unequalled accuracy and
stability, at a price comparable with analog monitors. With typical modulation, the CMR's
true ratio readout is a factor of 10 more stable than instruments that measure normalized
amplitude, and its phase readout is rock solid. Phase sign is automatic; no extra
operation. Practically, these features mean quick, accurate log or remote readings. The
CMR is fully remoteable via land or telemetry, using standard remote control equipment. An
optional repeater-controller is available for hardwire remote
control and readout via multiconductor cable at distances up to 1500 feet.
The CMR's outstanding performance and reasonable price make it ideal for new DA installations
or for modernizing the instrumentation of existing stations.
- True Ratio reading. Non-Reference and Reference
amplitudes are serparately measured and divided electronically to give an accurate digital
reading (and an equally accurate D.C. voltage for remote readings) that will not vary with
carrier level, and is exceptionally stable under conditions of deep, unsymmetric
- Stable, accurate phase reading with automatic phase
- Amplitude or True Ratio may be selected for
measurement with a front panel switch . Optional common point terminal for measuring
common point amplitude.
- Designed for Reliability and Maintainability. MIL
Spec. PC boards with plated through holes. Gold plated switch and relay contacts. Relays
have been tested to 10 to the seventh operations without failing. All ICs and relays are
socketed. Each unit is burned in at least one week to expose early IC failure.
- Dual Surge Protection. Gas Discharge tubes across
the sample line terminations, plus a relay that drops out when the monitor is not being
interrogated and disconnects the sample lines from the electronics, protect against
lighting induced sample line surges.
- LEVEL Meter simplifies installation.
- Accurate. Typically exceeds FCC specs. by
- Narrow phase - sign ambiguity (typically, +0.1 degrees)
give accurate phase readings near zero or 180 degrees.
- One year warranty.
- Frequency range: 500 - 2000 khz.
- Up to six towers, DA1 or DA2.
- 50 or 75 ohm terminations, N or UHF sample line receptacles.
range - 0 - 1.999
resolution - .001
accuracy - typical .5% or better. FCC spec.; 2% for ratios from .5 to 1.0, 5% for ratios
from .2 to .5.
D.C. output for remote reading via telemetry or phone line - max. voltage; 4.5 VDC for
ratios of 1.999. Linearity .5% or better. Minimum load, 4000 ohms.
range - 0 to +/-180 degrees
resolution - 0.1 degrees
accuracy - typically 0.5 degrees or better. FCC Spec.; 2 degrees for ratios from .2 to .5,
1 degrees for ratios from .5 to 1.0.
D.C output for remote reading via telemetry or
phone line - max. voltage; 5 VDC for 180 degrees phase. Linearity .3% or better. Minimum
load 4000 ohms.
Phase sign - automatic display. TTL level output for remote reading.
- Remote Tower Selection; - by means of external contact closures - max. contact current
60 ma. DC.
- Sample Signal Range; 1.8-15 VRMS.
- Power - 108-132 V., 6 Watts, 50-60 hz.
- Temperature - 0-50 degree C.
- Display Blanking - automatic when monitor is not being interrogated.
- BCD output. Multiplexed, at TTL levels with 1 TTL load fanout. Four BCD lines, Four
Digit Select Lines, one parameter select line, one phase sign line. (Intended for use with
CMR - 1 remote controller - repeater.)
- Dimension - 19" Rack mount, 5 1/4" high, 6 1/2" deep. LED readout are
- Common point input (amplitude readout regardless of
Ratio-Amplitude switch setting)
- To order specify number of towers, number patterns, sample
line impedance, and type of connector on sample line at monitor end (type N or UHF). Also
please supply operating frequency.
Cable to interconnect remote control equipment.