When I Transmit my the display shows my Voltage Drops Shawn June 30, 2016 21:40 Updated A voltage drop during transmit is normal on the SR-655HPC, SR-955HPC & SR-89MC. Related articles Change radio display to show volts? My 655hpc has a D.C. Low on the screen. What does this mean? How do I calibrate the SWR meter on my radio? How many amps does the SR-955HPC radio draw? Common factors that cause high SWR readings Comments 0 comments Article is closed for comments.