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ORD-VC-1 Universal booster with adjustable output between 1.6 AND 25 Amp.


By Peter Giling


With the available high power bridges, it was obvious to start doing something with it.
This booster will put all previous boosters from GCA in the background.
It is very small, only 70 x 60 x 50 mm, and can be used from 1 to Z scale.
The base of this booster is an IBT-2 bridge unit.
This unit has a maximum power option to 42 Amp, but this booster is designed not to handle more than 25 Amp.
Short circuit shut off is handled on-board and maximum current is selectable by dip switch. (See below)
On top of IBT-2 unit a board is situated that has all the necessary equipment for booster function.
This board contains two small processors and various opto-couplers for isolated input and output.
Booster also has so-called cut-out for use with Railcom
Th ebooster starts automaticaly, when correct pulses are coming in.
Processor IC1 is controlling the output pulses, and will switch off when pulses are incorrect or not available.
Processor IC1 also handles the cut-out for Railcom.
Processor IC5 handles the maximum selected current.
When the output exceeds the selected value, booster is shut off, and will try to start again every second.
Inputs for LocoNet Railsync, DCC232 (direct drive inside Rocrail) and CDE (lenz).
Also any central station can be used to drive this booster.
Power for this booster should be a DC output power supply, and the maximum Amp output of this power supply should be
ALWAYS slightly more than the selected Amp on booster.
The long run test proves that it is absolutely necessary to use a small fan for cooling , when the booster does more than 10 Amps.
So a small fan was added, which kept it below 40°C.
But on the maximum load of 25 Amp, a larger fan is undoubtedly needed.
Also, the position of the unit, where air can freely stream in upside direction through the cooling grid is essential.


  • Useable for Railcom
  • Easy selectable maximum output current.
  • Input for Railsync (LocNet)
  • Input for DCC232 (inside Rocrail, no central station needed.
  • With extra adapter also useable for DCC232 via USB.
  • Input for CDE (Lenz)
  • Only extra cooling needed, if continuous output is more that 16 Amp.(Can be done by small 40x40 mm fan,)
  • All signal inputs are isolated.
  • Absolute maximum power input 24Vdc.
  • also available without Railcom.(with additional firmware in IC1)
  • also available for DDX with Motorola/DCC mixed signals (with additional firmware).
  • opto_isolated output for short_circuit indication.

The hardware.


Hex files for Chip type Remark
IC1 PIC12F629 Railcom enabled
IC5 PIC12F675 max current controller
IC1 Universal firmware for IC1 PIC12F675 Railcom disabled

Mounting instructions

The ORD-VC-12 board is mounted on top of IBT-2.
The 1st edition of this board needed a small wire to +V of the IBT-2, for supply.
In the presented edition, this is changed.
The elco located besides the screw terminals on IBT-2, needs to be removed, to make place for 3-pins header (with middle pin removed).
C1 on ORD-VC-1 board is connected to these pins, replacing the removed elco.
On ORD-VC-1 board a 3-pin female header (middle pin removed.) is used two connect together.
Pricelist for al available kits and pcb is here.
The kits will have mounting supports, which need to be used in the way as shown here

Selection of Volts for Power supply

The choice of power supply depends of the used scale.

Scale Volt
N 12..15
H0 15..19
0 18..22
G 18..24
1 18..24

Current selection (IMPORTANT!)

Since this unit can handle a large current , it is necessary to select the maximum current output.
For example: If you use a power supply of 18V 4 Amp, the selection should be maximum 3 Amp on the booster.
When power supply can not handle the maximum selected current, the booster will not be able to shut off when a short
circuit occurrs.
This can cause much damage to your materials, and maybe fire hazard.
A special remark is to be stated for current versus wires, both between Booster and rails and also between booster and power supply.
Do NEVER use wire that cannot handle the selected maximum current.
A global indication:

Max current (Amp) wire diameter
mm² AWG
3 0,75 21
10 1,5 15
16 2,5 10
20 4 6

Current selection table (also printed on-board)
Amp max Dipswitch
1 2 3

Using multiple boosters.

It might be a bit overdone, but if the need for multiple boosters is there, be sure not to mix different type of boosters with ORD-VC-1.
With any multi-booster combination on the same track, it is extremely advised to use only 100% equal boosters !

LED indicator.

L1 just shows that 5 Volt power is available.
L2 is On when booster is in normal function.
L2 flashes fast (8 /sec) when short circuit is found (booster is off).
L2 flashes slower (3/sec) when no pulses are coming in.

Signal input connections.

This booster needs a digital signal (DCC or Motorola) from any central unit.
These can be connected in different ways.

LN1 (RJ12 connector)

This connector is mainly used for LocoNet
The signals in LocoNet (called Railsync) are connected to Pin 1 and 6.\]\

RS1 Serial connector (possible usb)

Here a signal directly from Rocrail can be used
In Rocrail this can be the internal command station DDX or DCC232.
Used pin in the SUB-D9 connector are pin 3&5.

CDE1 connector

Rail connections from any digital central unit can be connected to PIN C & D
Here also a galvanic free output is available which will indicate a short circuit situation.
These pins E and GND can be connected to any input port, for your own convenience.
It is not much used, the booster controls its own short circuit protections,
but if you like it could be used to report back to the controlling pc program, that booster is off.

ord-vc-1-en.txt · Last modified: 2021/05/14 14:49 by phg