Micron Tx20Sv2 Operation manual

Uplands House, Castle Howard Road, Malton YO17 6NJ
www.micronradiocontrol.co.uk
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Tx20Sv2 User Information
Tx20Sv2 is a hand-held wireless transmitter intended to control one model
railway live steam locomotive or a battery electric locomotive with the ESC set
to low-off throttle. Tx20Sv2 has a large knob for regulator control plus a
smaller knob for valve gear (or ESC direction control) and three push buttons
for auxiliary functions (e.g. a whistle servo).
Technology
Tx20Sv2 uses the 2.4GHz band which requires no frequency channel
control and is very resilient against interference. All radio frequency
components are contained on the internal Tx2 module. There are no user
adjustable parts on this module and it should not be modified.
Tx20Sv2 is compatible with all DSM2 receivers; this includes all Deltang
receivers and many Spektrum plus 3rd part Spektrum compatible receivers.
Any number of receivers can be bound to your Tx20Sv2 but only one should normally be switched
on at a time to operate them independently.
Range is suitable for indoors and small outdoor sites; the outdoor free-air range to a Deltang
receiver is at least 50m. Range indoors is affected by building construction materials, furniture,
people and receiver installation.
The regulator and direction knob movemements and bind push button action are transmitted as
separate R/C 'channels' which must match the receiver configuration:
Control R/C Channel Channel Value
regulator knob: 1
F1 button: 2 button up = mid, button down = low
direction knob: 3
F2 button: 4 button up = mid, button down = low
bind/F3 button: 5 button up = high, button down = low
Battery
The Tx20Sv2 uses a PP3 9V battery, preferably Alkaline or NiMH / Lithium
rechargeable. The maximum working voltage of the internal electronics module is 10V
and there is a protection diode wired in series with the battery lead. This allows the
battery voltage to be up to 10.7V. If the battery voltage is above this value, the
internal regulator will shut down and the transmitter will not operate.
To replace the battery:
Make sure that the power on/off button is off (up) before) adding or removing a battery.
Remove the lid at the bottom rear of the case by sliding it downwards. When Tx20Sv2 is new this will
require a bit of effort to slide it past the retaning 'click'. The image at the right shows the case rear with
the battery lid removed.
Remove the battery from the compartment and pull the battery clip off the terminals. Replace the clip
on the new battery which will only fit one way round. TAKE CARE, if force is needed, the connector is
probably the wrong way round.
Replace the battery cover by sliding it up from the bottom making sure that the retaining tab goes
under the case rear. The battery is held in place with a piece of foam attached to the cover and you will
feel some resistance as the cover is pushed down onto the battery.
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On / Off Push Button
Tx20Sv2 has an illuminated push-button latching on/off switch on the top panel. The LED lights continuously
when the transmitter is on and flashes when Tx20Sv2 is in bind mode (see below). It is best to switch the
transmitter on before the receiver. If a receiver is switched on with Tx20Sv2 off, it is likely to enter bind
mode with rapid flashing of the LED on the receiver board. If you did not intend to bind, switch the receiver
off, then switch Tx20Sv2 on followed by the receiver.
Regulator Knob
The regulator control is low-off with no centre-click and operates R/C channel 1. Off/Stop is at the fully
counter-clockwise rotation (left/CCW) of the knob and speed increases at the knob is rotated clockwise
(right/CW).
Direction Knob
The direction control has a centre-click and operates R/C channel 3. It is typically used to control a servo
connected to the loco reversing gear. If used with a receiver that has built-in ESC, the receiver must be
configured for 'low off', full-range motor control.
F1 & F2 Push Buttons
The two auxiliary function push buttons F1 and F2 may be used to control lighting, couplers, sound cards,
etc. All model rail receivers available from Micron can be configured with momentary (press for on, release
for off) or latching (press for on, press again for off) outputs that may be operated by F1 or F2.
Bind/F3 Button
Note: holding the bind button for longer than 20 seconds will result in strange things happening (see
Calibration).
If a receiver has not previously been bound, it has to be 'paired' with the transmitter. Binding is only
required once per receiver.
1. Put your receiver into bind mode (if a Deltang Rx4 or Rx6 receiver, switch it on and wait for the LED to
flash fast).
2. Press and hold the bind push button on the transmitter.
3. Switch the transmitter on by pushing the power button and then release the bind button.
4. Binding is complete when the receiver LED stops flashing.
The bind button also operates R/C channel 5 and this can be used to control another servo - e.g. for
operating a steam whistle.
Deltang Receiver Programming
You need to refer to the receiver's programming instructions for details of the available functions and the
programming sequence to modify the functions.
The universal method of putting Deltang receivers into programming mode requires R/C channels 2 and 4 -
buttons F1 and F2. The alternative method is to tap out Morse ‘SOS’ on the Bind/F3 button.
To Enter Programming Mode using F1 and F2:
1. Centre the direction knob
2. Switch the Tx on and hold down both F1 and F2
3. Apply power to the Rx and its LED will start rapid flashing
4. Release F1 and F2
The Rx LED will now show a 1-flash – this is a repeated single short flash followed by a longer pause.
This first flash pattern is called the 'Menu' in the programming instructions.
To Enter Programming Mode using the SOS method:
1. Centre the direction knob
2. Switch the Tx and Rx on and wait for the Rx LED to stay on solid; you should now have normal control
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of the model
3. Wait at least 5 seconds without touching any controls
4. Tap out the morse code ‘SOS’ on the bind button (… --- …)
dots (…) will be a quick press of the button and must be less than 0.7 seconds in duration
dashes (---) must be greater than 0.7 seconds and shorter than 5 seconds – 2 seconds is a reliable
time
the time between each dot or dash must be less than 5 seconds
5. If the SOS pattern is recognised, the Rx LED will display a repeating single-flash (1-flash pause and
repeat)
6. If you do not get the 1-flash, go back to step 3 and repeat the SOS
7. Switch the Rx off at any time to abort
To make changes to receiver settings:
One programming change requires up to five choices to be made. These are called 'levels' and each has
several options. They are documented in the programming table for the particular receiver; the Micron web
page description for a receiver contains a link to the programming table for that receiver. Completion of a
programming change exits programming mode and requires the F1/F2 or SOS method to be entered again
for the next change.
You have to remember which level you are changing and the repeating LED flashes display the current option
for that level. It is a good idea to write the programming sequence on a piece of scrap paper and cross off
each digit as it is entered. You always start at level 1. For example, the first choice is the Menu number
(programming group). The first option (1-flash) is for changing 'H' (ESC) outputs, the second (2-flash) is
Menu 2 to change P outputs for servos, 3-flash is for Menu 3 to change P outputs for on/off switching, etc.
Refer to the Programming Table for your receiver to find the number of options and what they change. Each
level is in a separate column, 1 to 5 left to right.
For example, to configure a Deltang Rx6 receiver output P4 to switch on (3.3V) when F1 is pressed (R/C
channel 2 is low), the programming sequence is 3,4,1,2,1, where:
3 = Menu 3
4 = P4
1 = momentary on/off
2 = R/C channel 2
3 = output idle 0V, 3.3V when channel is high (F1 pressed)
The general procedure for entering a programming sequence is, for each level:
rotate the direction knob Rev/CCW and back to centre to increment the Rx LED flash count (called NO
choices in the Deltang documentation); repeat this until the Rx LED is showing the correct flash count
for the programming level
rotate the direction knob Fwd/CW and back to centre to accept the current flash count for the current
level (called a YES choice in Deltang documentation) and move on to the next level in the programming
sequence
When you make a choice with the direction knob (Fwd or Rev), the Rx LED will briefly flash rapidly and then
the LED will:
direction knob Fwd/CW: display the current flash count for the next programming level or light solid
when the end of the programming sequence is reached
direction knob Rev/CCW: display the next flash count for the current level; each programming level
has a maximum flash count after which the flash count returns to 1 with another Rev/CCW movement
of the direction knob
Changes are saved automatically when the Rx LED lights solid at the end of a programming sequence. If a
mistake is made mid way through a sequence, switch the Rx off to abort.
Repeat the above steps for each program function that you wish to alter.
For example, to set the ESC output (the first if the receiver has multiple ESC) to respond to full range
regulator on channel 1 and direction control on channel 3, the programme sequence is 1,1,2,1,3:
Enter programming mode
Rx LED displays 1-flash, direction knob Fwd/CW to accept
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Rx LED displays 1-flash, direction knob Fwd/CW to accept
If rx LED does not display 2-flash, rotate direction knob Rev/CCW until it does, then direction knob
Fwd/CW to accept
If Rx LED does not display 1-flash, rotate direction knob Rev/CCW until it does, then direction knob
Fwd/CW to accept
If Rx LED does not display 3-flash, rotate direction knob Rev/CCW until it does, then direction knob
Fwd/CW to accept
Rx LED lights solid
Calibration
All ready-to-use transmitters are calibrated as the final manufacturing step. This normally only needs to be
done once. If you suspect that the regulator control is not operating correctly or you have replaced any of the
internal components (e.g. regulator potentiometer), your transmitter may need calibration.
If the bind button has been inadvertently held down for longer than 20 seconds, the previously stored
calibration data will have been overwritten and you could find that the regulator control behaves strangely.
To perform calibration:
Centre the regulator knob (white mark pointing toward the top of the Tx)
Centre the direction knob
Switch the Tx on
Within 60 seconds, press and hold the bind button
After 20 seconds, the Tx LED will go off
Release the bind button, the Tx LED come back on
The Tx is now calibrated.
© Micron Radio Control
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