html JI1FGX/DU9 Mindanao, Philippines Amateur radio diary IOTA OC-130/3.5MHz antenna, stepping motor this and that (2025/05/16)
JI1FGX/DU9 Mindanao, Philippines Amateur Radio Diary IOTA OC-130
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Access until yesterday
Introduction. [Lily Diary]
Diary of Life in Mindanao

25/06/07  Introducing the Shack
25/06/06  A portrait illustrated by ChatGPT
25/05/26 Windows full-width half-width switching
25/05/17 OK2ZAW BCD to 16 converter
25/05/16 For 3.5MHz zepp antennas
Stepping motor this and that
25/05/15 3.5MHz stepping motor plan
25/05/14 3.5MHz tuning coil installed
25/05/11 3.5MHz antenna installation completed
25/05/03 JTDX automatic operation program Ver0.4.3
25/04/26 Drone Habsan ZINO
25/04/25 Time setting Ver0.3
25/04/24 AutoCWType_Ver1.3
25/04/23 FTDX3000 LCD repair preparation
25/04/22 Installation plan for 3.5 MHz Twep antenna
25/04/21 AutoCWType_Ver1.1
25/04/20 10,14MHz antenna installation completed
25/04/19 JTDX automatic operation program Ver0.4.1
25/04/19 Antenna pole installation at 14 MHz
25/04/18 ThinkPad X390 repair completed
25/04/17 Search is now available.
25/04/15 Preparation of 10 MHz dipole
25/04/12 Hexbeam Part8
25/04/06 ThinkPad X390 is broken.
25/04/05 Time Setting Program
25/03/31 JTDX Automatic Operation Program
25/03/30 Automatic log sending from CWType to Hamlog
25/03/21 Hexbeam Part7
25/03/20 FreeDV Part3 First QSO
25/03/18 FreeDV Part2 QSO in shack
25/03/16 Hexbeam Part6
25/03/15 FreeDV Part1 installation
25/03/09 Hexbeam Part5
25/03/07 Hexbeam Part4
25/03/05 28MHz antenna modification
25/03/01 FTDX3000 is broken!
25/02/28 Pile up at 50MHz FT8
25/02/28 DXV500ZS linear amplifier repair
25/02/27 Pipe and rebuild plan for tower
25/02/26 Direction of Japan from Ozamiz
25/02/26 28MHz does not fly.
25/02/23 DXV500ZS linear amplifier repair
25/02/22 Hexbeam Part3
25/02/21 Hexbeam Part2
25/02/18 28MHz antenna construction
25/02/17 18,24MHz antenna height construction
25/02/16 Z26NS Cosovo
25/02/14 21MHz FT8
25/02/12 Antenna repair at 7,21 MHz
25/02/08 CW operation at 21MHz
25/02/05 DXV500ZS linear amplifier failure
25/01/19 Input Director
25/01/14 Temporary License Renewal
3.5MHz antenna, stepping motor this and that (2025/05/16)
On the use of a stepping motor for remote tuning of a tuning barycon for a 3.5 MHz Twep antenna
I looked up a few things on ChatGPT.
I did get some information from ChatGPT about the step IR antenna,
Other information about stepping motors was almost the same as yesterday's information from JG2TST Matsui.
I asked ChatGPT about the step IR yagi antenna.

The following is a description of the stepper motor drive system used in SteppIR antennas (e.g., SteppIR 3-elec., BigIR, etc.) and its relationship to the controller:

Overview of Stepping Motor Drive of SteppIR Antenna
Driving system:
SteppIR typically uses bipolar stepping motors, driven by
  • Motor is installed in the antenna body (element base)
  • Controller (e.g. SDA100) is installed in the shack
  • 4 wires A+/A-/B+/B- wired directly from shack to antenna
For this reason, many users pull 20 to 30 m of thick cable (shielded twisted pair) for motor drive.

Put the controller near the motor? →.NO
In the SteppIR stock, the motor controller is located in the shack and is extended to the motor by power lines (A+/A-/B+/B-). It is not controlled by step, direction, or enable (PUL/DIR/EN) signal wires.
Is the EN/DIR/PUL system (STEP/DIR control) stable?
This is a common CNC control method and is often used in motor control ICs (e.g., TMC, A4988, DM556, etc.).

Conditions for stabilization with this method:
  • Since STEP/DIR/EN are digital signals, they are more resistant to noise than motor power lines and can be sent over a long distance in a stable manner.
  • Communication distance: Stable operation at 30m (twisted pair + shield recommended)
  • If this method is used, the driver board should ideally be placed near the motor and only PUL/DIR/EN should be sent from the shack.
(data) item SteppIR genuine method STEP/DIR method (for homebrewers)
Motor Drive Directly from the shack driver. Driver near motor
Wiring distance 20-30m motor power line 30m signal line
Noise Effects susceptible Hard to receive (reinforced by twisted pair)
stability Dependent on cable quality High (conditional)
Homebrewing Difficulty Level Low (genuine use) High (driver selection and design required)
Recommended electric wire
For motor power lines Shielded twisted pair x 2 pairs (AWG18-16)
For STEP/DIR/EN signal line Shielded LAN cables (CAT6 STP, etc.) are acceptable
If using ZK-SMC01 and TB6600, it is much more stable to pull 30m of EN/DIR/PUL signal line than to pull 30m of A+, A-, B+, B- motor line.
Comparison items A+, A-,B+, B- Direct drive EN/DIR/PUL signal control
Signal type High current, analogous Constant current, digital
Noise Characteristics Low (large inductive noise effect) High (can be counteracted by twisted pair)
distance tolerance Possible voltage drop and malfunction over long distances More than 30m is possible (shield recommended)
stability Dependent on cable quality Relatively stable
Recommended configuration
  • ZK-SMC01 (pulse output) installed on shack side
  • Place the TB6600 in the immediate vicinity of the motor (in an outdoor case)
  • Draw 3 wires (+GND) of EN/DIR/PUL with twisted pair or STP cable (LAN cable diversion is also acceptable)