The TLS-13 from GeoSync Microwave is a Test Loop Translator with Downlink Frequency 0.95 to 1.45 GHz, Uplink Frequency 12.75 to 13.25 GHz, LO Frequency 11.8 GHz, Attenuation Adjustment Range 30 dB. Tags: Single Band. More details for TLS-13 can be seen below.