Individual
light control for hübner's VT98 with #4070 decoder.
This page shows rebuilding light
control system of hübner's VT98.
Tasks of project:
- Rebuild the control system for
lighting, get individual light control for head/tail
lighting and room lighting.
- No modification for #4070 decoder.
Original lighting
control system:
- hübner's VT98 has feature for
digital light functions.
- The original light function can
not switch the head/tail lights and room light
individually.
- Original decoder#1400 has only one
function output.
- New #4070 decoder with sound
effect circuit internally has two function output('FL'
and 'AUX1').
Comparison of original
and rebuild lighting control system:
| |
Room
|
Head/Tail
|
Original
|
Rebuild
|
|
OFF
|
OFF
|
YES
|
YES
|
|
OFF
|
ON
|
NO
|
YES
|
|
ON
|
OFF
|
NO*
|
YES
|
|
ON
|
ON
|
YES
|
YES
|
*It can be by change the CV
setting. See bottom of this page.
Hardware rebuild:
- It requires small rebuild for
basement printed circuit board.
Points:
- Cut the print pattern at the point
of yellow arrow (print pattern between #13 pin of ST1
connector and thru hole).
- Solder new by-pass jump wire
pointed by red arrow (connect thru hole from #13 pin of
ST1 and axle contact).
Software rebuild
(change the CV's setting):
Points:
- Change these CV's setting for
individual control of 'FL' and 'AUX1'.
CV No.
|
Description of CV
|
Default
value
|
New
value
|
CV33
|
Output Location FL(f)
|
5
|
1
|
CV34
|
Output Location FL(r)
|
6
|
2
|
CV39
|
output Location F5
|
0
|
1
|
Further tips:
- Even if you change the CV's
setting without
hardware rebuild you
can control room light individually, but you can't select
'roomlight=off, head/tail light=on' combination. If you
want to turn on the head light you must always turn on
room light.
- If you change the CV40's
value(Output Location F6, default value= '0') to
value='4' you can get 'shunting mode' similar to that of
marklin's #60955 decoder.
How to control?:
- To on/ off the head/ tail light
push function / off button of the control unit.
- To on/ off the room light push the
F5 button of the control unit.
- This configurations are based
on above CV's setting chart.
- The button for control may
vary by CV's setting.
Conclusion:
- The fully digital light control
achieved.
- No modify for decoder.
- No more 'lamp lit in the daytime'!
Note:
- This modify apply to only for #4070 decoder. You can not get same
function by using #1400 or #1405 decoders(they have only one function output).
- If you use marklin's #6021 control
unit, you can not
use F5 or F6. So you must program these functions for
F1,F2,F3 or F4. Then you must give up some sound fuction
(door? pressure air? horn? or engine???).
- This modify(including CV setting
re-programming) is tested with uhrenblock's Intellibox. I
don't know what will happened if you use another digital
centers.
Copyright © 2000 by Jun Maeda / KOBE JAPAN