HF 400W Linear Amp. ・ The HL-450B has a built-in auto band-select function. It uses a newly developed micro processor based technology, and works a smooth automatic operation when driven by the radio in either SSB or CW mode. In addition, manual band setting is possible as well. It is designed to be "user friendly". ・ Since the HL-450B is compatible with our optional external remote controller (HRC-60), operation is possible from remote locations, if plugged into the socket at the rear panel. ・ The HL-450B is equipped with a hard-key terminal to make a smooth send / receive switching with the radio. Built-in ALC circuit helps suppress excessive output and avoid the signal distortion. ・ The HL-450B has various protection circuits such as for high antenna SWR, over drive, over current etc. When any abnormal condition is detected, operation is automatically shut down to prevent the failure. ・ The large analog power meter is easy to read and the output can always be monitored. Specifications  Frequency Range All HF amateur bands of 3.5 - 28MHz (including all WARC bands)  Mode SSB / CW / FM  Output Power SSB (PEP) / CW 400W max. 350W typ., 300W min.  RF Input 50W  DC Power Supply DC 13.8V 60A max.  Input / Output 50 ohms  Final Transistor THP-120 x 4  Cooling System Forced Air Cooling  Input / Output  Connector UHF (SO-239)  Input / Output 50 ohms  Built-in functions 　1. Send / receive switching terminal (hard key) 　2. Protection circuit  (antenna SWR, over-current, over- 　　 voltage, over-drive, over-temperature, band mis-set) 　3. Output power meter 　4. ALC terminal 　5. External controller  (HRC-60, optional parts) terminal  Accessories 　DC Power Cord (red / black pair) 6' x 1, Coaxial Jumper Cable : 　2' x1, Stand-by Cable (with RCA plug) 4' x 1, Spare Fuses: 30A 　x 4, Instruction Manual, Warranty Card  Dimensions  (W) x (H) x (D) Approx. 300 x 100 x 342 mm Approx. 8.7 x 3.5 x 13 inches  Weight Approx. 5 kgs./ Approx. 11 lbs.  Optional Accessories External remote controller ： HRC-60  Price Contact us