• Transmitter “HotRC CT-4A”
  • Power on
  • Power off
  • Power LED (red)
  • Mixed LED (green)
  • Lock mode (Green LED “MIXED”)
  • Neutral position trim adjustment (CH1 & CH2)
  • Max stroke adjustment (CH1 & CH2)
  • Reversal of signal (CH1 & CH2)
  • Mixed/Hybrid control of CH1 & CH2
  • Fail save
  • Modes for CH3 & CH4
  • Uni-, bidirectional CH2
  • ?
• Receiver “HotRC F-04A”
  • Green LED
  • Blue LED “digital” and “analog” mode
  • Switch between “digital” and “analog” mode
  • Bind
  • Fail save, lost connection function (Out of control protection)

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Transmitter “HotRC CT-4A”

Power on

• Press and hold ON
• Ascending tone series can be heard
• Release ON

Power off

• Press and hold ON
• Decending tone series can be heard
• Release ON

Power LED (red)

• Permanently on → Power OK
• Blinking (and repeated beeping) → Low Battery

Mixed LED (green)

• on: Some setting possibilities are deactivated
• off: Some setting possibilities are activated

Lock mode (Green LED “MIXED”)

Enable or disable lock mode

• Power off
• Press and hold CH4
• Power on
• Release all
  -> Green LED "MIXED" is toggled (Illuminated = lock enabled)
  Some setting possibilities are deactivated in lock mode

Neutral position trim adjustment (CH1 & CH2)

Lock mode must be deactivated to make this setting.

• Power on
• Press or hold ST.TRIM +/- for CH1 or TH.TRIM +/- for CH2
• A short, high-pitched beep indicates adjustment
• A longer, lower beep indicates the center position

Max stroke adjustment (CH1 & CH2)

• Power off
• Press and hold REV
• Power on
• POWER is blinking
• Release REV
• Press or hold ST.TRIM +/- CH1 or TH.TRIM +/- for CH2
• A short, high-pitched beep indicates adjustment
• A longer, lower beep indicates the minimal or maximal setting
• Use the steering wheel to test the current min and max setting
• Press REV to confirm the setting. (Two longer beeps)

Reversal of signal (CH1 & CH2)

Lock mode must be deactivated to make this setting.

• Power on
• Press and hold REV (It beeps continuously)
• Rotate the CH1 wheel or CH2 throttle in the desired direction
• It beeps twice as confirmation
• Release REV

Mixed/Hybrid control of CH1 & CH2

Steering with two motors.

• Power off
• Press and hold CH3
• Power on
• Release all

Fail save

Lost connection defaults, out of control protection)

• Power off
• Press and hold TH.TRIM -
• Press ON
• ON LED is blinking + beeping (Receiver might show blinkcode for "Out of control protection" setup mode)
• Adjust and hold channels as you want them to be as default
• Press TH.TRIM - to set the Current channel values as defaults

Modes for CH3 & CH4

Switch between toggle or up/down mode for CH3 & CH4

• Power off
• Press and hold ST.TRIM -
• Power on

Uni-, bidirectional CH2

Switch between unidirectional or bidirectional mode of CH2

• Power off
• Press and hold TH.TRIM +
• Power on
  (Observation: When the receiver is turned on and the throttle is pressed, this mode maybe is automatically set.)

?

• Power off
• Press and hold ST.TRIM +
• POWER LED is blinking
• ??
• Press ST.TRIM - to exit

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Receiver “HotRC F-04A”

Green LED

• Slowly blinking → No connection to transmitter
• Fast blinking → not paired
• Continuously lit → Connected to transmitter

Blue LED “digital” and “analog” mode

• Off → PWM signal with period of 20ms (50Hz). 50% duty cycle is the neutral position. Called "analog mode"
  ​​​​ ┏━━━━━┓     ┏━━━━━┓ 
  ​​​​ ┃     ┃     ┃     ┃
  ​​​​━┛     ┗━━━━━┛     ┗━━
  ​​​​ ├─50%─┤
  ​​​​ ├────20ms───┤
  

• On → Square signal every 3ms (333Hz). (Positive signal length unknown.) Called "digital mode"
• Fast blinking (together with fast blinking green LED) → "Out of control protection" setup mode

Switch between “digital” and “analog” mode

• Press and hold BIND for 5 seconds
• Blue LED indicator changes mode
• Release BIND

Bind

• Turn transmitter off
• Green LED of receiver flashes slowly
• Press BIND
• Green LED of receiver flashes fast
• Turn on the transmitter
• Green LED of receiver lit continuously

Fail save, lost connection function (Out of control protection)

See instruction for transmitter

https://www.youtube.com/watch?v=AY9xh2v6Wjs