Modellbahn Digital Peter Stärz Selectrix DHR-PIC User manual

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Modellbahn Digital Peter Stärz
Dresdener Str. 68 – D-02977 Hoyerswerda –  [phone] – www.firma-staerz.de – [e-mail]
Loco Controller
with 3-digit Display
for Selectrix, Selectrix-2, DCC and Motorola
with SX-Bus-Plug
DHR-PIC
v1a-2013
Degree of difficulty: easy
medium
difficult
Necessary skills:
- Assembly of the PCB
- Drill, countersink und saw/mill the case
- Dismantle and wiring a 5-pole cable
The Loco Controller DHR-PIC is a comfortable and easy to
use hand control unit with SX-Bus-Plug supporting several
protocols.
Additionally to Selectrix also the digital formats Selectrix-2,
DCC and Motorola are supported. That allows the Control
Panel SPF-PIC not only to be used in combination with the
Professional Central Unit ZS1, but also with the Digital Central
Unit ZS2 or the MTTM FCC.
Five keys and one rotary switch and the 3-digits display grant
easy access to controlling locomotives in address range 0 to
999 – also with one hand only.
Special features
- supports Selectrix, Selectrix-2, DCC, Motorola
- Easy handling
Table of content
Special features ................................................................................1
Technical specifications....................................................................2
Compatibility ..................................................................................2
Kit contents........................................................................................2
Maintenance and care ......................................................................2
Assembly instruction .........................................................................3
Component layout diagram on the PCB .......................................3
Populated PCB ..............................................................................3
Drilling template.............................................................................4
Description of operation....................................................................5
Bringing into service......................................................................5
Signs and symbols ........................................................................5
Selection of a locomotive ..............................................................5
Controlling locomotives .................................................................5

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Technical specifications
Compatibility
The following table lists the digital formats and address ranges
supported by the Loco Controller DHR-PIC. The Loco Controller
DHR-PIC connects to the central unit via the SX-bus.
That makes the Loco Controller DHR-PIC compatible with all
Selectrix-only central units and with central units that are equipped
with an SX-bus and where the support of different digital formats is
based on the Selectrix frame extension.
Supported digital formats and address ranges
The Loco Controller DHR-PIC supports the following digital for-
mats and address ranges:
Digital format Address range Speed steps
Selectrix 0 – 103 0 – 31
Selectrix-2 1 – 999 0 – 127
DCC, short addresses 1 – 127 0 – 28
DCC, long addresses 1 – 999 0 – 28
Motorola (MM new) 1 – 255 0 – 28
Size
74mm x 125mm x 27mm
Power supply
The power supply is provided by the SX-bus.
Display
3-digits display
Plugging
The Loco Controller DHR-PIC is delivered with an SX-bus cable. It
can be hot-plugged to any of the model railway’s SX-bus jacks.
The Loco Controller DHR-PIC must never be connected to the PX-
bus!
Assembly notes
The Loco Controller DHR-PIC is assembled following the instruc-
tions on the next page. For soldering the components on the PCB
a soldering station with the temperate set to approx. 400°C is
needed together with 0.5 or 1.0 mm soldering wire with rosin flux.
No special tools are required. Do not use soldering flux! Pay atten-
tion to solder speedy to avoid device damage by overheating.
Be aware that the PCB mounts from the two sides. For assembly
of the case a drill machine (or a portable electric drill), according
drill bits (2,0 mm, 7 mm) and a countersink for M2 counter-sunk
screws is required.
Non-Use
When the Loco Controller DHR-PIC is not used it should be stored
at a dry and clean place.
The Instruction
The full content of the instruction is important. Very important
information is marked in colours; critical information is highlighted
in red.
Kit contents
Please first verify that the kit contains all the components listed
below.
General parts:
1x PCB
1x 28-pin IC socket
1x voltage regulator 78L05
5x push buttons
1x rotary switch
3x 7-segment-element
1x display frame with red glass
1x SX-bus cable (insulated at one side)
1x cable strap
1x case and sticker
1x rotary knob with cover
4x counter-sunk screw long
4x washers
12x threaded stud
ICs:
1x PIC16F913
1x LM339N
Transistors:
1x transistor BC557
3x transistor BC547
Capacitors (marking):
2x electrolytic 47µF
3x ceramic 100nF (104Z)
2x ceramic 220pF (221)
Resistors (marking):
2x 10kOhm (brown, black, black, red, brown)
11x 22kOhm (red, red, black, red, brown)
6x 4,7kOhm (yellow, lilac, black, brown, brown)
8x 680Ohm (blue, grey, black, black, brown)
2x 100Ohm (brown, black, black, black, brown)
1x 120Ohm (brown, red, black, black, brown)
Maintenance and care
The Controller DHR-PIC should be cleaned from time to time by
blowing or wiping.
The use of any kind of liquid for cleaning is prohibited explicitly.
Please also visit our FAQ page at www.firma-staerz.de for any
question first.

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Assembly instruction
Assemble the kit in the order of these instructions. All components
(except the push buttons, rotary switch and 7-segment-elements)
are placed on the top side of the PCB (marked “top”) as close to
the PCB as possible and soldered on the bottom side of the PCB
(marked “Bottom”). The Push buttons, rotary switch and 7-
segment-elements are placed on the bottom side and also
soldered on that side. All devices have to be placed abso-
lutely plane and equally and must not distance nor bias the
PCB. Use a bending tool (e.g. Conrad 425869 – 62) for bending.
Cut the leads of components flush using a wire cutter after solder-
ing.
Solder cleanly and precisely!
1. Resistors
Bend the resistor leads for 7.5 mm pitch before insertion. To facili-
tate placing components on the PCB support the edges of the
board with the help of two books, for instance, to leave enough
space for the leads under the board. Insert the resistors on board
aligning the coloured rings of all the resistors in the same way to
make it easier to verify the value of the resistors later. Place a
suitable plane piece of wood or similar on top of the resistors on
board. Turn the board together with the wood upside down. The
underside of the board is now conveniently accessible for solder-
ing the components.
Solder one end of each resistor first and check that they are posi-
tioned properly before soldering the other end of each resistor.
R1, R2: 10kOhm (brown, black, black, red, brown)
R3: 120Ohm (brown, red, black, black, brown)
R4, R5: 100Ohm (brown, black, black, black, brown)
R6-R11: 4,7kOhm (yellow, lilac, black, brown, brown)
R12-R22: 22kOhm (red, red, black, red, brown)
R23-R30: 680Ohm (blue, grey, black, black, brown)
2. Socket for PIC, IC
Place and solder the PIC socket and IC3 with the notches accord-
ing to the component layout diagram on the PCB.
IC3: LM339N
Sockel: Socket for PIC
3. Ceramic capacitors
C1 - C3: 100nF (104)
C6, C7: 220pF (221)
4. Transistors and voltage regulator
The transistor and the voltage regulator can be placed simultane-
ously when proceeding similar to the resistors. Do not confuse the
transistors BC547 and BC557 with the voltage regulator 78L05!
Q1: BC557 (flat bright labelled front)
Q2-Q4: BC547 (flat bright labelled front)
IC2 78L05 (black front)
5. 7-segment-element, push buttons and rotary switch
Place and solder these in this order on the bottom side of the PCB.
Watch out to place 7-segment-elements with the correct orienta-
tion (dots downwards).
6. Electrolytic capacitors, watch polarity!
Electrolytic capacitors are placed reclined. The positive pole
(longer lead) of C4 and C5 must face to the left, so that minus
poles show towards the shielding.
C4, C5: 47µF
7. Wiring the SX-bus cable
Verify that one of the pins of the SX-bus cable is shortened. The
cable is soldered to the corresponding pads on the PCB. To do so
dismantle and tin the single wires for about 5 mm and route them
through the top side to the bottom side and solder here. Pay atten-
tion to not damage the insulations of single wires while soldering
another.
Non insulated: Shielding Yellow: T1
Black: D Orange/Green: +B
Red: GND Brown/Blue: T0
Especially watch out not to violate the insulation of the single
wires. The Shield (“Schirm”) must never get in contact with other
pins (e.g. pins of the push buttons).
Finally the cable is fixed on the PCB using the cable strap. The
cable strap must be tightened in a way that a reliable strain relief is
granted. The end of the cable strap must be on the top side of the
PCB (see image on the following page).
Component layout diagram on the PCB
Populated PCB
8. Verification and mounting the PIC
After soldering all components on the PCB verify once more that
they are placed according component layout diagram and that they
are oriented properly. Check that all solder points on the bottom
side of the PCB look correct. Note especially if there are any un-
desired solder bridges between solder pads.
After verification the PIC can be mounted (Notch to R8).
9. Preparing the top case part
The case is to be drilled at several places. To do so, use the drill-
ing template printed on the very last page of these instructions and
work very carefully. The PCB might not fit the case properly when
to big tolerances occur.
The case top is the flat one of the two case parts.
1. Cut out the drilling template (see below) precisely.
2. Lay the drilling template into the inner side of the case top part
and fix it e.g. by some scotch at the four edges.
3. Use a needle to mark drill holes.
4. Scratch the display frame with a sharp tool.
5. Check not to have forgotten any drill hole.
6. Dismantle scotch and drill mask.

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7. Use drill of 2.0 mm pitch to pre-drill all holes.
8. Re-drill the bigger holes of 7.0 mm.
9. Counter-sink the holes of 2 mm. Use a 90°-counter-sunk.
10. Use a fine fret saw or similar to saw the display frame and
clean the edges with a fine file.
10. Preparing the bottom case part
The case has to be prepared to contain the cable corresponding to
the following drawing by milling or sawing.
33,5
5
5
Einfräsung
11. Mounting into the case
After concluding the assembly of the main PCB and the display
module, they are mounted to the top case part.
1. Insert the 4 long counter-sunk screws from the case front (A,
B, C, D), add 2 washers each and tightened with 1 short
threaded stud.
2. Cut out the white areas of the front sticker and attach it to the
case. The sticker matches exactly the framed part of the case.
Work very precisely here.
3. Add one washer each, mount the main PCB and fix it with the
remaining 4 short threaded studs.
4. Mount the bottom case part and fix it using the case screws.
Pay once again attention not to quench the SX-bus cable.
5. The rotary knob is assembled. Leave a space of about 1mm to
the front to ensure the push button option of the rotary switch
6. Attach the cover to the rotary knob.
Drilling template
Please cut this drilling template carefully and use it for the case according to the assembly instruction point 9
Displayausschnitt
fräsen
D
46,0
2
1
,
5
28,2
8
,
7
C
A
B
Respect the following remark if you
print this document yourself:
You may only use this drilling
template if you printed this docu-
ment in original size!
To do so, select “Page adjust-
ments: None” in your printer set-
tings.
The template has to have a width of
119.2 mm.

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Description of operation
Bringing into service
After assembling the Loco Controller DHR-PIC can be hot-plugged
to any of the model railway’s SX-bus jacks.
At start-up the start screen indicating the software version of the
Loco Controller DHR-PIC is displayed for a few moments.
Then it is switched to the menu  Selection of a locomotive
where you enter the address and digital format for the locomotive
to choose.
Signs and symbols
In these instructions the following symbols are used:
symbol name Explanation
ZE Press button ZE.
Turns on and off the power of the rails
Lok Press button Lok.
Opens the menu  selection of locomotives
Li Press button “light”
Switches on and off the loco light
F Press button F
Activates second loco function
< > Press button “<>”
Changes direction of travel of the loco
Push Press rotary switch
Confirm selection (function varies)
Turn Turn rotary switch
Change selection (function varies)
 Link to other section of these instructions
Selection of a locomotive
When switching to the locomotive selection menu, the format and
the address of the locomotive are chosen.
In the following pictograms blinking is represented by a white
hollow.
Selection of digital format
The selected digital format is indicated by blinking points whereas
the numbers indicate the address of the locomotive (of the se-
lected format)
Change to menu selection of
a locomotive
(last used loco (here SX1) is
displayed)
Changes to another digital
format
(here: Selectrix-2)
DCC, short addresses:
center and right points blink
DCC, long addresses:
left and center point blink
Motorola (MM new):
left point blinks
Selection of an address
After the selection of the digital format the address of the locomo-
tive can be chosen.
Blinking numbers highlight the current position which is being
changed.
Iterates addresses in single
steps (only available for
Selectrix-1, DCC (short) and
Motorola)
Switch to mode of entering
address of locomotive digit
by digit
Switch to right next position.
(Confirms selection at right
most position)
Move one position to the left
(e.g. to correct address).
Quit selection menu.
The last displayed address
can now be controlled.
Controlling locomotives
In normal driving mode where one loco is selected ( Selection of
a locomotive), the following control actions can be carried out and
are displayed as show in the pictograms:
Switch on or off
the power on the rails
Turn on and off
second loco function
Turn on and off
light
Changes direc
tion of travel of
the loco
(here: forwards)
Changes direction of travel of
the loco
(here: backwards)
Change loco speed
(here SX1-Loco: max. 31
speed steps, forwards)
Change loco speed
(here SX2-Loco: max. 127
speed steps, forwards)
Res
et speed to 0 and change
direction of travel
If the selected locomotive is controlled by a second controller (e.g.
second loco controller or central unit), changes are immediately
indicated on the display.
All brands and trademarks are property of their respective owners.
Modellbahn Digital Peter Stärz, Dresdener Str. 68, D-02977 Hoyerswerda, Germany
Illustrations and technical data are subject to change. We are not responsible for printing or typographical errors. Printable version of 17.06.2019