HCM 870 BBMG Torque 20mm HV CL Digital Servo
HCM 870 BBMG Torque 20mm HV CL Digital Servo

HCM 870 BBMG Torque 20mm HV CL Digital Servo

P/N: S4073


Equipped with all-metal parts designed for durability and extreme operations, the Graupner HCM 870 BBMG Torque High-Voltage Coreless Digital Servo provides reliable high torque and great speed under extreme conditions with consistent control input performance.  Optimized for high voltage input (8.4V), the HCM servos are specially designed to provide speed and holding power with low dead-band technology for extra reliability and precision while the aluminum case allows for lower operating temperatures and better run times.

Fully programmable to meet your unique specifications via the free Graupner Servo Setup Software, the HBM 870 BBMG is ideal for large scale airplanes and as a swashplate and tail servo for medium to large size helicopters.


  • Coreless motor
  • Full aluminum body
  • High Voltage
  • Faster response time and longer run time
  • At least five times more durable and 30% faster response times than brushed servos
  • Programmable digital circuit and SMT circuitry
  • 2048 high resolution
  • Supporting 1-16µ depending on programming
  • Wide frame rate range of 20Hz-400Hz
  • 12-bit processing circuit (At least twice resolution comparing to 10-bit processing circuit)


  • Swash and tail servo for 700-800 helicopters
  • IMAC class airplanes
  • Large 3D airplanes
  • Large scale airplanes


  • HCM 870 BBMG High-Voltage Digital Servo
  • Horn set