Companion receiver for the SD-31 Synthesizer-Detector, automatically tuned to the generator for RF bridge measurements.Potomac RX-31 Companion Receiver for SD-31SKU: RX-31 $2,855.00 Regular Price$2,757.67Sale PriceExcluding Sales Tax | Shipping PolicyQuantity*Add to CartBrandPotomac InstrumentsProduct DetailsManufacturer: Potomac InstrumentsManufacturer part number: RX-31Sold by: Radio Gearheads, 705 Eaton Ave N, Fosston, MN 56542 Questions about compatibility, configuration or lead time? Call 1-800-992-1506 or use Get A Quote.