Monday, August 24, 2015

Getting started with Deltang radio control in the garden

Following some discussions on garden railway forums such as the Garden Railway Forum and G Scale Central, I have come to realise that the sheer range and diversity of Deltang radio control equipment can appear quite daunting for those those starting out with radio control. The information on the Deltang website (and to be honest, sometimes in my blog postings) often assumes background knowledge which not everyone possesses. This blog posting (and subsequent posts in this series) aims to demystify the process of getting started with Deltang radio control equipment for garden railway modellers (and maybe others as well).

I have no formal qualifications in electronics but I've been dabbling with Deltang radio control gear for about the past three years and in that time have learned a fair bit - mostly by making and correcting mistakes. Hopefully that will help me to see things from a beginner's perspective. This guide has been checked for accuracy by David Theunissen of Deltang and been given the all clear by a fellow garden railway modeller who was formerly an electrical engineer and is an accomplished electronics hobbyist. Any errors, though, are my own. Hopefully this posting will smooth your passage into making the most of Deltang radio control equipment.

Contents

  • The basic principles of Deltang radio control
  • Binding the receiver to the transmitter
  • Deltang transmitter
  • Deltang receivers
  • Ordering Deltang equipment
  • Examples of locomotives equipped with Deltang receivers

The basic principles of Deltang radio control

Skip this section if you are already au fait with how 2.4gHz radio control equipment works.

The basic components of a traditional radio control system for battery locos are: a transmitter and a receiver connected directly to an Electronic Speed Control (ESC) unit which in turn is connected to the batteries and the motor. When the throttle joystick (or knob) on the transmitter is moved the motor increases in speed.

The Deltang system uses the same principle, but the ESC is combined with the receiver on the same (very small) circuit board.

The receiver/controller can be used with any Spektrum DSM2 transmitter but, to my mind, is most effective when used with one of the purpose-made Deltang transmitters.

For more detailed and generalised information about battery power and radio control see - Getting started with battery power and radio control

Binding

With the 2.4gHz system, a receiver needs to be bound to a particular transmitter.  Once bound, the receiver remembers the settings and does not normally need to bound again - unless you want to bind it to a different transmitter.

When a Deltang receiver is initially turned on, its LED flashes once a second to show it is hunting for the transmitter to which it has been bound. If after about 20 seconds, it has not found its transmitter (or it is new and has not yet been bound), the LED starts flashing rapidly indicating it has now gone into 'bind mode'. To bind it to a Deltang transmitter, the transmitter is turned on while the bind button is being held down.

The LED on the transmitter starts flashing and within a short space of time, the LED on the receiver should begin flashing in unison with it. Shortly afterwards both LEDs stop flashing and remain steady, showing the receiver has been bound to the transmitter and can respond to signals sent from it.

Subsequently, provided its bound transmitter is on, when the receiver is turned on again, its LED will initially flash once a second until it latches on to its transmitter, then the LED will remain on steadily.

See the second part of this video for a demonstration of the bind process with an Rx60 receiver and a Tx22 transmitter:

An unlimited number of receivers can be bound to one transmitter, so several locomotives could be controlled by one transmitter. This means that, provided you only run one loco at a time, you only need one transmitter to control a whole fleet of locos. However, one of the clever features of some Deltang transmitters (eg the Tx22) is their ability to independently control several locomotives at the same time.

Deltang Transmitters

Rather than a joystick, Deltang transmitters have a speed control knob which, under normal circumstances, can be used to control both speed and direction.

Tx20/21

The most basic Deltang transmitter is the Tx20.

This features a speed control knob, a direction switch (which can be used to control accessories if not needed for direction control), two accessory push buttons, a bind button and an on/off switch. Like all Deltang transmitters, it is powered by a PP3 9 volt battery which I find lasts for months.

Normally, the speed control knob controls both speed and direction (centre off, twist one way for forward and the other way for reverse). All Deltang receivers can be purchased and/or re-programmed to operate differently and so, if you want fine control or prefer using a direction switch, then a receiver can be purchased or programmed to use the full length of turn of the speed knob to increase and decrease speed and the switch to change direction. (See How to program Deltang receivers ) and/or see the Variants section in Receivers below for more information).

I have constructed a Tx20 from a kit and described the building process here - How I constructed a Deltang Tx20 transmitter from a kit - pending 

The Tx21 version of this transmitter has a knob in place of the two push buttons. This simulates inertia so when the speed knob is turned, the loco gradually builds up or decreases its speed, the time taken to do this depending on how far the inertia knob has been turned. When the inertia control is set to zero, the loco responds directly to the speed knob.

I have a Tx21 transmitter which I built from a kit. I use this transmitter as a spare, being particularly useful when I have more than one operator.

Tx22

To my mind, the Tx22 is the most versatile of the Deltang transmitters.

In addition to the bind button, on/off button, direction switch and the inertia and speed knobs, the Tx22 has a 12-position selector (Selecta) switch. A different loco can be bound to each of the 12 positions of the Selecta switch (or of course several locos can be bound to each position).

Clicking the Selecta switch to position 1, will put the transmitter in control of whichever loco is bound to position 1. Even if they are switched on, none of the other locos which have been bound to other positions on the Selecta switch will move or change what they are doing. Loco No. 1 could be set in motion and then the switch clicked to position No.3 (say). Loco No. 1 will continue at the same speed while Loco No. 3 is being controlled by the transmitter. Switching back to position 1 will enable the transmitter to gain control of Loco No. 1 again.

Tx22 is the transmitter I use most frequently because I can control all eleven of my battery locos from it (I've not yet converted a twelfth loco to battery power - but it is scheduled)

Deltang Receivers

The sheer range of receivers on the Deltang website can be baffling and slightly mind-blowing at first, so hopefully this section will help you to decide which is most appropriate for you when getting started. Basically, I use only two types of Deltang receiver in locos on my garden railway, depending on the use to which they will be put. There are other receivers which could be used, but for now, let's keep things simple.

Rx60

When I first started using Deltang equipment, the Rx60 was the receiver was the only receiver available which most suited my needs. I have continued to use it and its subsequent variants.

The first thing you notice about the Rx60 is its size - it is tiny when compared to more traditional receivers and ESCs - it measures only 11mm x 22.5mm.

It can cope with 3-13 volts and up to 1.3amps, which is quite adequate for many of the small and not so small locomotives which you may want to run in the garden. Until the introduction of the Rx65 (see below), I used this for all my locos except one, whose motor and gear train meant it sometimes drew over 1.5 amps and so control became somewhat erratic (see Jessie section below).

It in addition to the outputs controlling the motor, it has five additional outputs. Outputs 1 and 2 are pre-programmed to provide automatic directional lighting (1 = forward, 2 = reverse), outputs 3-5 respond to the switches on Deltang transmitters (3 = direction switch left, 4 = direction switch right, 5 = bind button). These outputs can be used for accessories such as interior lighting, or to trigger events on soundcards such as the whistle. I use the bind button on my transmitters to sound the horn or whistle on locos equipped with sound cards (see How to use Deltang receiver output pads).

I have replaced the Rx60 receivers in some of my locos with Rx65 receivers as some larger and heavier loco motors buzzed when when running at slow speed. This has been eliminated completely with the Rx65. (see Sharp Stewart section below)

For more information on ordering specific types of Rx60 receiver see Variants section below.

Rx65

The Rx65 receiver has been developed and produced more recently in response to requests for a more powerful receiver/controller.

As you can see from the photo, it is bigger than the Rx60 (18mm x 35mm) and has a lot more output pads. It is still quite small compared with other rx / ESC systems but has the advantage that the output pads are easier to solder on to. It handles up to 3 amps and 3-18 volts. It can manage up to 6 amps if used with a daughter board, but for now that's beyond the scope of this introductory posting.

The Rx65 has ten outputs, two of which are pre-programmed for direction lighting, the rest responding in different ways to the switches and buttons on Deltang transmitters (see How to use Deltang receiver pads).

Variants

This is an aspect which at first can seem quite baffling for the uninitiated. When ordering Deltang receivers, you need to specify which variation on the basic receiver you require.

The main variants of receivers appropriate for garden railway models are:
  • 1 - responds to the direction switch on the transmitter 
  • 2 - uses the speed control knob to change direction (and speed)
  • 22 - for use with a Tx22 with Selecta switch
With these connectors
  • N - No wires attached
  • W - Tx covered in heat shrink insulation and wires soldered to the power supply and motor terminals
In addition the Rx65 can be supplied with the following connectors
  • R = Red JST plugs for power and motor leads
  • S = Screw terminal for power and motor connections
and/or with a longer aerial 
  • U = long aerial

When ordering you therefore specify the type of variations you require. for example:

Rx65-22-W

would get you an Rx65 receiver, programmed to respond to the Selecta switch on the Tx22, covered in clear heatshrink insulation with the power leads and motor leads already attached

This is the version which I tend to use most frequently now as, although I can solder on my own leads, it's quicker and easier to have a receiver ready to fit.

Whereas:
Rx65-1-SU

would result in an Rx65 receiver, for use with a Tx20/1 transmitter, using the direction switch to change direction,  having a long aerial and with screw terminals for the motor and power supply.

Ordering Deltang equipment

In addition to the suppliers listed on the Deltang website, it is possible to order directly from David at Deltang, by sending him an email specifying your requirements and asking for a PayPal invoice. His email address is - dt AT flyelectric DOT org DOT uk (replacing the AT with @ and the DOTs with full stops). I have found that as soon as I have settled the Paypal invoice during the day, the equipment usually arrives the following day by first class mail.

Examples of locomotives equipped with Deltang receivers.

IP Engineering Lollypop Railcar

This little kit is no longer available from IP Engineering, but I made it to test the feasibility of using Deltang receivers with small, low powered locos.

It is powered by three 1.2v NiMh Low Self Discharge (LSD) batteries which I bought from Hobbyking and uses an Rx60-22-W receiver/controller. As with the majority of my locos, I fit an auto-reset fuse to protect the batteries from accidental short circuit and I use a two way switch to connect the batteries to either the motor or the charge socket, so the batteries can be recharged without having to remove them from the loco.

The charge socket and auto reset fuse are both from Maplin:

 Everything sits loosely inside the body of the railcar. I could have used double-sided sticky pads to fix everything in place, but as I'm always tinkering and experimenting, I like to have the option of easy and quick removal.

I have also made use of output pads 1 and 2 on the receiver to operate directional lighting LEDs in the front and rear lamps (see How to use Deltang receiver pads). For more information about the construction of this railcar see (How I constructed an IP Engineering Lollypop railcar kit).

Sharp Stewart loco No. 5

This was my third scratchbuilt loco, was based on the Southwold Railway loco No. 1, Southwold and made use of a Playmobil 0-4-0 motor block.

There was room inside the main body of the loco for a 12v li-ion CCTV battery pack.

These can be purchased from China through eBay, though these days shipping them to the UK can be problematical as airlines are reluctant to carry li-ion batteries. These batteries include protection circuits against over-discharge and short-circuit and also to monitor charging. Some people are very wary of using li-ion batteries because of their volatility, but I am of the opinion that if you take adequate precautions then the benefits they bring (eg compact size, battery capacity) are worth the added risks.

I included an additional 1.6A auto-reset circuit breaker as added protection. Originally, I used an Rx60 receiver, .....

.... but this has recently replaced with an Rx65b, which cured the buzz made by the motor when running at low speed. The basic circuit for this loco is much the same as for all my locos,

After construction, I added a MyLocoSound steam soundcard to this loco and made use of one of the output pads to sound the whistle when the bind button is pressed on the Tx22 transmitter (see How to use Deltang receiver pads).

For more information on the construction of this locomotive see - How I constructed a Sharp Stewart 2-4-2T locomotive

Peckett Loco No. 1

This was the first UK outline loco which I constructed from a GRS (Garden Railway Specialists) kit, mounted on an LGB ToyTrain 0-4-0 motor block. When I converted it from track-power to battery power, I wanted to make the conversion as quick and easy as I could and so, rather than dismantling the loco to find room for batteries, I placed three 3.7v 18650, lithium-ion batteries in the cab.

 As lithium-ion batteries need a lot more careful management than other types of battery, I wired a them into a battery protection board (purchased on eBay) which protects them against short circuit, over discharge and manages balance charging of the batteries (ie ensuring the batteries are equally charged).

It uses a Deltang Rx65b receiver. The wiring for this loco is slightly more complex than for the previous locos, but the principles are the same.

For more information about the construction and conversion of this loco see - How I constructed a Peckett loco and How I converted a Peckett loco from track power to battery power.

An IP Engineering 'Jessie' diesel locomotive

I have included this loco as it takes a different approach to any of the previous examples. Rather than using an Rx60 or Rx65 receiver/controller, it uses an Rx102 receiver connected to a Brian Jones Mac5 ESC.  The model was made from a kit and has worked its way through four different mechanisms, it now being powered by a USA Trains 0-4-0 motor block.

The original mechanisms in this loco tended to draw more amps than the Rx60 could manage and so, having already got a Mac5 ESC to hand, I opted for the combination of an Rx102-1H receiver connected to it.

It was originally powered by ten 1.2v NiMh batteries, but these have recently been replaced with three 18650 3.7v li-ion batteries and a battery protection board, similar to that used in the Peckett loco above.

I have added a Peter Spoerer / Mtroniks diesel sound card to this loco and use outputs from the receiver to trigger the horn (when the bind button is pressed) and to start and stop the engine sound (using the direction switch) (see How to use Deltang receiver output pads).

Update - 17/9/15
Since writing this entry, I have replaced the above arrangement with a Deltang Rx65b receiver/controller. I have described the installation in detail here - How I installed a Deltang Rx65b in my IP Engineering Jessie



As has been indicated above. I intend to follow-up this blog posting with more postings addressing other aspects of Deltang radio control:
I hope this little introduction to Deltang proves useful. If you have any queries or suggestions for improvements (or spot any ambiguities) then please let me know.

9 comments:

Philip said...

Brilliant Rik, thanks very much. Looking forward to the rest of the series.

Ge Rik said...

Thanks Philip
Might take a little while to produce the follow-ups. I had already started on this one a while back and so wasn't starting from scratch. I've also just found out I didn't take any pictures when I constructed the Tx21 and so may have to make another one (always handy to have a spare) when funds permit.

Rik

BaBBLR said...

Excellent Rik,
This will be a great resource for those wondering how to negotiate the complexities of Deltang's myriad options.

Phil

Rob said...

Thanks for posting this Rik, just what I need as I'm about to install this equipment in my Swift Sixteen 'Tin Turtle'.

Ge Rik said...

Thanks Phil - I was hoping it was sufficient to get someone started and then maybe look into some of the other options on offer

Rob - glad it's helpful. Really like the SS Tin Turtle - I'm tempted myself but as originally I only intended to have three locos on the PLR, and I'm now up to twelve, I think I've reached capacity (for now). Would love to see pictures and a video of the TT in action.

Anonymous said...

Thank you for posting this. Very informative.

Ge Rik said...

Thanks Anon
I've now started marketing my own versions of Deltang transmitter - see
http://rctrains.co.uk/

Rik

strawbrick said...

I have been drawn to this site by an article in the August 1716 MM Today magazine by Bob Brown entitled "Experiences with the Deltang radio control system.
I have a "mixed" 12v dc controlled by a resistance controller and live steam garden layout, with the locos radio controlled.
I have the following thoughts / queries:
- Is it feasible to convert the track feed to 16 v ac and use Deltang as the equivalent of a digital controller?
- Is it possible to use Deltang to control actuators on the steam loco controls.
Many thanks for any assistance.
John H

Ge Rik said...

Hi Jon H
I don't have any direct experience of using Deltang to control 16v AC, sorry. In theory, it should be possible and I know some have tried it - but no idea how successful they were. You wouldn't be able to use the 12 loco Selecta sytem if you are going to retain track power, though. Maybe posting an enquiry on the 16mm Assoc or G1 forums might get a reply from some who have already trodden the path.