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MODEL 5212A
LOOPBACK RECEIVER MODULE
(Optional Measurement : MODEL 5212A-M)

General Description: The Loopback Receiver allows you to remotely test and diagnose telecommunication networks. This includes leased telephone lines and microwave paths. It measures signal strength, loss noise level and sinad. It is housed on a single type 10 plug in module. The DTMF address ability of the unit allows complex communication networks to be analyzed via identifying its address and function. Addressing is further enhanced by "Wild Card" addressing for simultaneous functions by groups.
Correct levels in a communication link can be achieved in test systems which only measure level. However, levels which are thought to be correct can cause distortion. The Model 5212A provides an easy method to detect clipping distortion.
The front panel keyboard allows local control of all functions including a LCD display to indicate the function in progress. Relay expanders are available as optional accessories and occupy adjacent slots.
To accommodate telco and/or microwave systems the loopback gain can be set to each dB from +24dB to -31dB.
TEST FUNCTIONS:
- Loopback mode for measuring round-trip impairments.
- DTMF identification of the remotes address and selected function.
- Generate a tone sequence from 404 to 2804 Hz (every 200 Hz except 2604) at "reference level" for inbound frequency response measurements.
- Generate 1004 Hz at "0 dB reference level" for mid-band loss.
- Generate 1004 Hz at "reference level -13 dB" to detect compression.
- Amputate to provide a way to silence an offending remote.
- Quiet Termination mode to facilitate noise measurements.
- Generate a tone sequence from 404 to 2804 Hz (every 200 Hz except 2604) at "reference level -13 dB" to detect level compression versus frequency.
- Generate 2804 Hz at "reference level" for high frequency loss.
- Un-timed loopback mode for long term round trip measurements.
- Causes Model 5212A-M to measure outbound loss versus frequency.
- Simultaneous 857 and 863 Hz for intermodulation measurement.
- Controls and uncommitted SPDT contact for digital loopback or other functions.
- Optional relay expander boards provide 8 DTMF controlled relays in adjacent rack spaces and up to 64 relays.
SPECIFICATIONS:
- Controls & Indicators: 12 button keypad for local mode select with a LCD display to indicate selection.
- Module Address: 4 module address selection.
- Power Supply: 12, 24 or 48 Vdc; (230 mA @ 12 Vdc, 126 mA @ 24 Vdc, 135 mA @ 48 Vdc).
- Loopback Gain: Programmable in 1 dB steps from +24dB to -31dB.
- Loopback Output Level: Up to +7 dBm into 600 ohm or 900 ohm.
- Loopback Frequency Response: +/-0.3 dB from 0.3 to 4 kHz.
- Loopback Distortion: 0.25% maximum THD [Total Harmonic Distortion]
- Operating Temperature: -30 ° C to +70 ° C
- Storage Temperature: -55 ° C to +85 ° C
- Dimensions: 5.6" H x 1.5" W x 6.0" D.
MEASUREMENT OPTION
The Model 5212A with Measurement Option can measure the level and frequency of a 300-3000 Hz tone and send that measurement in a DTMF string to be decoded by Model 5106 Base Master with Path Monitor Software.