User's Manual

Help is available from the Hitec office through phone support and e-mail inquiries.
Our US office is generally open Monday thru Friday, 8:00AM to 4:30PM PST.
These hours and days may vary by season. Every attempt is made to answer every incoming service call.
Should you get voice mail, leave your name and number and a staff member will return your call.
Make plans to visit the Hitec website, www.hitecrcd.com, on a regular basis. Not only is it full of specs and other
informaction about the entire Hitec product line, our FAQ pages will eventually hold valuable information and
program update about the OPTIMA D receiver.
One of the bene_ts of the extensive R/C online community is the vast wealth of archived knowledge available.
Hitec sponsors forums on most of the popular R/C web sites where a Hitec staff_ member or representative tries
to answer all manner of product related questions.
Bringing together strangers with common interests is proving to be one of the greatest gifts of the internet. If
past history is any guide to the future, we are certain forums will be started about the Hitec 2.4 system and
several are certain to stand out as valuable archives of information
All Hitec products carry a two year from date of purchase warranty against manufactures defects.
Our trained and professional service representative will determine if the item will be repaired or replaced. To
provide all the necessary information we need to administrate your repair, visit our website at www.hitecrcd.com
and download the repair form, _ll it out and send in your item for repair.
Receiver Model Size Weight
SRX12 46.5 x 35.5 x 15.7mm 21g
MRX3 38.8 x 20.2 x 11.5mm 6.5g
Operation Voltage : NiMH, NiCD – 4~6 cell (4.8V~7.2V) or Li-Po – 2 cell (7.4V) can be used.Up to 7.4V BEC power
from ESC also can be used.
SRX12  SPC port allow to use up to 70V (4.8V~70.0V).
1. LED
Indicates the set-up process codes and current status of the receiver. (Please refer to page 2 for more detail)
2. System Power Input & Servo Signal Output Port
Supplying power to Receiver System, Servo, Bus system and Sensor accessories from RX Battery.
Signal output port. External Battery Voltage, SPC Input Port.
PWM Output Port
- SRX 12 – General Servo can use in CH1~CH12 Port.
- MRX 3 – General Servo can use in CH1~CH3 Port
Single Line( SL ) Output Port ( SRX 12, MRX 3 )
- With SL function, Futaba S-Bus or PPM can be selected. Please select suitable Bus system based on your
device. (Please refer to ID Link section for more detail)
Sensor Output Port *MSB* (SRX 12)
- Multiplex M-Link Sensor can be connected and can use in SRX 12 Receiver via MSB port
Voltage Sensor (MRX 3)
- MRX 3 can check External Battery voltage (Main Battery) using Voltage Sensor port up to 70V
( 4.8V~70V ). Voltage can be checked by Transmitter in real time.
SPC Power Input Port (SRX 12)
- Using SPC, SRX 12 can be operated from 4.8V to max 70V.
- When using SPC, separate servo power must be needed.
- (4.8~7.4V, 4~5cell NiMH/NiCd battery or Li-Po 2 cell Battery)