Metraplex 183-49 Signal Conditioner VCO Frequency Discriminator Rackmount

Metraplex 183-49 Signal Conditioner VCO Frequency Discriminator Rackmount

The Metraplex 183-49 is a rackmount multi-channel signal conditioner chassis populated with plug-in oscillator and discriminator modules. Built by Metraplex Corp. of Bethel, Connecticut, this unit houses a combination of I14 VCO (voltage-controlled oscillator) plug-in modules and I20 frequency discriminator plug-in modules, each carrying individual level indicators, adjustment controls, and BNC-connected I/O. The chassis accepts multiple plug-in cards and provides a dense array of BNC connectors on the rear panel for signal routing.

Specifications & What's Included

• Manufacturer: Metraplex Corp., Berkshire Industrial Park, Bethel, Connecticut 06801
• Part Number: 183-49
• Model No: 2934 (per label)
• Form Factor: Rackmount chassis
• Plug-in Module Type 1: I14 VCO Oscillator modules — frequencies 450 kHz ±20% and 64 kHz ±8 kHz; per-module controls: LIMIT, ZERO, GAIN, IN, OUTPUT, GRD
• Plug-in Module Type 2: I20 Frequency Discriminator modules — frequencies 450 kHz ±20% and 64 kHz ±8 kHz; per-module controls: LO IN, ZERO, LIMIT, HI, LO, OUT (CA / LP / GRD), meter indicator
• Approximately 4 I14 modules and 4 I20 modules visible and installed
• Rear panel: approximately 30 BNC connectors labeled J1 through J30
• Power supply: integrated with external heat sink and attached power cable
• Modules branded MFX (Metraplex)

Applications

Metraplex signal conditioner systems of this type were used extensively in aerospace telemetry, flight test data acquisition, and defense instrumentation programs from the 1970s through the 1990s. In telemetry systems, VCO oscillators convert analog sensor signals (voltage or current) into frequency-modulated subcarrier signals suitable for transmission or recording on an FM/FM multiplex recorder. The companion frequency discriminator modules demodulate those subcarrier signals back into analog voltages for downstream data processing or display. This type of modular plug-in chassis allowed ground stations and airborne data systems to condition, transmit, and recover data from many channels simultaneously across standardized IRIG subcarrier frequencies — the 450 kHz and 64 kHz bands visible on these modules are consistent with IRIG-106 FM/FM telemetry standards. These systems are still sought by organizations maintaining legacy telemetry infrastructure, calibration labs, and aerospace research facilities that operate older FM/FM data chains.