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Model Railway Electrics -
Infra-Red Control (IRC)
Author
"Silver
Surfer"
(forum member)
I'd always
considered going down the DCC route (I'm presently fully DC) but
wanted if possible to eliminate the need to have powered track.
I don't know why but I've always suffered from slow running
engines stalling on points etc and it's a real pain.
In the June 2007 edition of Railway Modeller was an article on
the Bodmin 0 gauge layout of Ray Green using Infra Red train
control. Could this be the answer to my prayers? I began
researching and a couple of days later saw me on a visit to
Steve Leyland at MicroMotive in Clay Cross Derbyshire, to have a
look at their IR system
'Red Arrow'
Needless to say I returned home with an IR system - a controller
and a bag of bits capable of fitting out two locomotive's
The Controller and
The Bit - (Which are left to
right)
Test Rig
After reading
the instructions several times I assembled a test rig to try out
the bits before attempting to fit them in a loco.
I only
used a small 3volt motor for the test but everything worked
great.
Now came the bit I really hated, butchering a loco and tender -
it always seems like sacrilege to deliberately damage something
you've probably treasured for years. So I called it surgery and
made every effort not to to more damage than was absolutely
necessary.
This picture shows the module on the back of
a Bachmann Jubilee tender - just to give an impression of size.
Module on
Tender
The first job
I did (I realised later that this should have been left until
later because if I couldn't get the module and battery in the
tender then this bit would have been pointless, still - lesson
learned) was to remove the power pickups from the loco, as I was
fitting a new power source.
No easy ride for me then.
Stripping the Jubilee, I soon realised there were no actual
pickups, but this one used a split metal chassis with two
springs pressing onto the motor contacts. MMmm.
Split Chassis
The two
little springs fitted in the holes shown. They simply pressed
against the motor contacts on the can. I decided to remove the
springs (saving them for later), isolate the contacts and take
two leads out the rear of the loco to the tender.
Isolated Contacts
The
rubber isolators shown didn't work as they were too bulky to
allow the sides of the chassis to be assembled correctly. I
eventually changed them for two small pieces of insulation
stripped from mains cable.
Motor Feeds Fitted
I
re-assembled the loco and simply hooked up a 9v battery to the
two leads. First thing I noticed (this was a new standard PP3
battery) was an apparent loss of power and the engine didn't
seem to go as fast as before. I stripped it down and
re-assembled it again - same result, so I placed the loco on
track and bingo it went as fast as before, so it must be the
fact it is powered by 9v instead of 12v. This may be a problem
when it hauls decent length trains but, as still had plenty to
do, would have to be tested later.
Now the butchery, sorry surgery, on the tender.
Inside the tender of the loco are three metal
plates used as ballast. My first go was to remove the middle one
and replace it with a suitably trimmed piece of plasticard which
I split across the middle, put them back in, creating a slot
through which I could thread a cable tie to secure everything
piggy back style.
Cable Tie Slot
I stacked the battery and
module onto the plates. A bit like this:-
Piggy Back (nb the little
thing sticking up at the coupling end is veroboard - see later)
In
addition to these bits, I still had to fit the detector, a reed
switch, a limit resistor, a bridge rectifier plus connections
etc - would I have room?
The switch was no problem. The
one supplied is a proximity reed switch supplied with a magnet.
In its normal state the contacts are closed - allowing a
circuit. Put the magnet onto it and the contacts break thus
breaking the circuit. A little test showed the magnet was
powerful enough to work through the tender sides.
Reed Switch
Using
double sided tape the switch was stuck to the underside rear of
the tender.
All I have to
do to turn off the power is to rest the magnet on top of the
tender as shown below.
I then had to
manufacture an assembly containing a bridge rectifier and a
limit resistor (which I think is
120 ohm. This is not absolutely necessary
but means dismantling the tender each time the battery goes
flat. What I wanted was to be able to charge the battery by
standing the loco on live track.
So a short while later
I had made this bit of kit (on the veroboard shown above) and
fitted all the parts onto the tender chassis and tried to put
the top on................Absolutely no way would they all go
in.
Think and re-think and re-re-think.
I then remembered a classic bit of advice my old Dad
gave me when I was repairing a motorbike or something:- "If you
can't get something to fit correctly, turn it upside down and
try again."
Exactly Dad, thanks. I was trying to put
everything on the chassis and hoping the top would fit. I took
everything off and placed it in the now upside down body shell,
which seemed much easier really.
Trying it again I was
till struggling for space, so out came the ballast plates and
their securing supports - just about do it if I place the
detector in the top but on one side of centre.
Packed In The Tender Shell
This view shows
the detector epoxied (glued) into the roof of the tender but
placed to one side to allow maximum room for the battery.
Internal View
and another view from the
topside - I have still to tidy this up as the epoxy seeped
through the gap a little.
Topside
HURRAH. Everything fitted - but would it
work?
Working Test
This shot shows the engine,
yet to be connected properly to the tender, under test. WORKED
FIRST TIME. The wheels are actually turning quickly but the
camera has frozen the action.
(note: Ignore the green wires
which will eventually be used as power pickups for the battery
re-harge system).
One or two problems but I got there.
I'm quite satisfied actually as, other than wiring up a few LED
circuits, I've absolutely no experience or knowledge of
electronics.
Problems detected and yet to be
resolved:
1) Apparent lack of power (9v versus 12v) will it
pull a train?.
2) The system allows
programming of 99 locos. Factory default sets all chips at 27
but I can't re-programme this one. It won't move off 27.
3) Reading the instructions I think I need a
transistor heatsink. I've a rough idea of what it is and what it
does but, how big is it, where do I fit it and where do I get it
from.
4) Still to fit power pickups
for battery re-charging. Should this be via tender wheels
(easier) or should I strap them on the loco split chassis
(better pickup)?
5) The jubilee has a moulded
coal load forming the roof of the shell. What to do about those
that have little or no coal?
6) Will the continual
charge/discharge ruin the battery.
7) Once finally
connected, the engine and tender are paired for life with the
wires going from one to the other. Can I find a miniature or
micro connector small enough to do the job?
Some things I have learned:
1)
It won't fit in tank engines.
2)
It won't fit in locos with tender drive motors.
Well
that's as far as I've gone so far. I'll keep you updated of
my progress.
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