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RS-160 Receiving System

RS-160 front

receiver and displays

tuners & options

WJ 1970 catalog (p 10)

RS-160 Receiving System

This is an almost fully configured RS-160. It consists of (from the top):

DRX-308 - frequency extender - boosts counter range to 1 GHz

SM-7301A (left) - spectrum monitor - displays pan, sector or both and can display for all tuners simultaneously.

DRO-308 (right) - early Nixie version of the frequency display for the RS-160. Replaced in later versions by the DRO-335 with LEDs and which did not require a DRX-308 to reach 1 GHz.

205-2 - receiver - the 205, 205-2 (added pan/sector), 215 (added digital remote control)or an number of -x variants specially configured to user needs

EC-160 - extender cable - couples the 205 receiver to the tuner rack. RS-160 can consist of a single tuner and displays or be coupled to a larger tuner rack. Tuners can also be plugged directly into the receiver for single band use.

CSU-160 - computer switching unit - (a misnomer because it is actually only digitally switched with discrete logic). This is the top of the line tuner rack. It holds seven tuners and can switch sequentially through the tuners by remote control to stitch together a spectral scan using several tuner ranges. It also supplies a increment voltage to move place the successive traces from different tuners on different horizontal CRT locations. Other options here are the TSU-160, a manual seven tuner rack that only sweeps one tuner at a time. and the TSU-103B which holds three tuners but can switch them automatically like the TSU-160.

This CSU-160 has a full set of tuners allowing coverage of 2-1000 MHz on one spectrum display. A list of available tuners is below.

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SM-7301 SDU, DRO-308 counter and 205-2 receiver

The RS-160 is an amazing system. Building a complete version is a difficult task as they were usually sent to the surplus market piecemeal.

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Available tuners


2-30 MHz


220-440 MHz


180-300 MHz


0.9-30 MHz


30-60 MHz


20-40 MHz


250-500 MHz


60-120 MHz


40-80 MHz


500-1000 MHz


100-180 MHz


50-100 MHz

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Other options

The RS-160 is a highly customizable system. They were produced for many years in many different configurations. It can be as simple as a receiver and one tuner with a Tektronix 604 X-Y display for pan/sec or an even larger and more complicated than the picture at the top of this page.

The main receiver can be a 205, 205-2, 215 or any of the myriad of 205-x variants that were made. The 215 receiver can be operated with an FS-101 frequency synthesizer for digital remote control. The main difference between the 215 and the 205 series is extensive interfaces for remote control inside the 215 presumably by a PDP-11 based system.

The frequency readout can be a Nixie display DRO-308 with or without the DRX-308 frequency extender or a newer LED display DRO-335.

Systems with multiple receivers could use the VM-101 marker generator which allows any receiver with a 21.4 MHz IF to display a tuning pip on the RS-160 display. In this manner, an intercept operator could quickly hone in on a suspect signal. This is essentially an early, non-digital version of the "handoff" feature popular newer surveillance radios. Up to five receivers could be connected to the VM-101.

See the Receiver Guide for more information on the receivers, the Systems Guide for more information on the RS-160 and the Accessories Guide for more information on the various parts.

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