RaceAmerica 3850C User manual

Model 3850C/CW/CZ Timer AC4
Rev G
Four Timer Autocross
Timing System
Owner’s Manual
RaceAmerica Corporation
105 Bonaventura Drive
San Jose, CA 95134
[phone]
www.raceamerica.com
[email protected]
Copyright 2020 RaceAmerica, Inc.

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RaceAmerica Model 3850 Timer AC4
Table of Contents
PRODUCT INFORMATION LINKS................................................................................................3
SET-UP STEPS - TIMER AC4 ..........................................................................................................4
PACKAGE COMPONENTS ..............................................................................................................5
POWER REQUIREMENTS...............................................................................................................5
PRODUCT SPECIFICATIONS .........................................................................................................5
THEORY OF OPERATION ...............................................................................................................5
AVALIABLE OPTIONS......................................................................................................................5
SET-UP STEPS - WIRELESS TIMER. ............................................................................................6
POWER-ON/SELF-TEST ..................................................................................................................7
SYSTEM SETTINGS ..........................................................................................................................7
FIGURE 1 - TLINK3 POWER AND CABLING CONNECTIONS...............................................8
CABLING DIAGRAMS......................................................................................................................9
SINGLE SENSOR .........................................................................................................................9
DUAL SENSOR ...........................................................................................................................10
CONNECTING SYSTEM OPTIONS........................................................................................11
CONSOLE FEATURES ..............................................................................................................12
CONFIGURATION MENU..............................................................................................................12
CONFIGURE PRINT HEADER.....................................................................................................12
ALIGNMENT MODE .......................................................................................................................13
Hard Wired Sensors........................................................................................................................13
T-Link Wireless Sensors .................................................................................................................13
CONSOLE CONFIGURATION ......................................................................................................13
SERIAL PORT CONFIGURATIONS .............................................................................................13
RF INTEGRITY.................................................................................................................................13
WIRELESS BATTERY LEVEL.......................................................................................................15
TIMER OPERATION .......................................................................................................................15
COUNTDOWN TIMER....................................................................................................................17
KEYPAD FUNCTIONS ....................................................................................................................17
STATUS DISPLAY MESSAGES......................................................................................................20
TECHNICAL DETAILS ...................................................................................................................21
MAINTENANCE...............................................................................................................................22
SPARE PARTS ...................................................................................................................................22
SUPPORT AGREEMENTS..............................................................................................................22
TIMESLIP HEADER ........................................................................................................................23
FOAM STAND INSTALLATION....................................................................................................25

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RaceAmerica Model 3850 Timer AC4
PRODUCT INFORMATION LINKS
RaceAmerica Website www.raceamerica.com
RaceAmerica Online Store store.raceamerica.com
Raceamerica Online Forum www.raceamerica.com/forum
Product Warranty www.raceamerica.com/legal.html
Service & Repairs www.raceamerica.com/service.html
Technical Assistance www.raceamerica.com/techcall.html
Owner’s Manuals www.raceamerica.com/prodpdf.html
Mounting Diagrams www.raceamerica.com/mountpdf.html
Product Catalog www.raceamerica.com/catalog.html

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RaceAmerica Model 3850 Timer AC4
INTRODUCTION
T-Link Wireless replaces track cables normally
used to connect track sensors to the timing system.
The T-Link connects to an external track sensor
using a short interconnect track cable.
NOTE: THIS PRODUCT OPERATES ON
HIGH FREQUENCY RADIO WAVES. DO
NOT POWER ON THE T-LINK WITHOUT
ATTACHNG THE ANTENNA AND DO NOT
OPERATE UNITS CLOSER TOGETHER
THAN FOUR FEET. ADDITIONALLY, DO
NOT PLUG ANY DEVICE IN THE CHAR-
GER PLUG BUT THE CHARGER. PLUG
ONLY DESIGNATED RACEAMERICA CA-
BLES IN THE T-PORT CONNECTOR.
Power is supplied to the timer console and
track sensor components of the 3850 Timer AC4
by the 12VDC automotive battery connected to
the RED and BLACK alligator clips or regulated
DC power source. Under normal conditions, a
properly charged battery will operate for an entire
day of racing without requiring a recharge.
The Beam Emitters and Track Sensors
operate on invisible (to the unaided human eye)
Infra Red (IR) light. The coded light frequencies
are constantly received (aligned) by the Track
Sensors until a car interrupts reception (‘breaks’
the beam).
The IR Beam Emitter to Track Sensor
transmission operates on Line-of-Sight principles.
This makes alignment of these units critical but
simple. Tips are provided to aid alignment on
surfaces that are other than ideal. These units
will operate over a wide range of conditions but
should not be operated beyond the specication
parameters (less than 4 ft or more than 50 ft).
Each T-Link unit is congured with a unique
ID code and a wireless optimizer code. These
codes are listed on the identity label located on
the bottom of the T-Link unit. Valid T-Link ID
codes are A and B. The wireless optimizer code
is also listed on the identity label for wireless
Model 5040/5050 - IR Beam Emitter
Picture shows top and bottom of units. Note
removable USB Battery Pack
Model 5140 - IR Track Sensor
Note cable connector is located in the side
facing away from the track. Track Sensors are
interchangeable with one another. Track Sensor
is pictured with both top and bottom sides up.
communications optimization and compatibility
with other T-Link units.
SET-UP STEPS - TIMER AC4
The Timer AC4 can be set up in Single (lap-
timer) or dual sensor (autocross Solo 1) congu-
rations and operated in either Manual, Hard-wired
or Wireless modes. Dierent keypad functions
are available with each mode; this manual will
highlight the dierences.
This manual will illustrate the console screen
four line display with each line in a dierent set of
brackets as follows - [SEnSor] [ALiGn] [S0--0F].
The console keypad utilizes dual function
keys. All functions shown in white function when
pressed; functions shown in yellow require the *
[SHIFT] key to be pressed two seconds before
the desired function key is pressed.

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RaceAmerica Model 3850 Timer AC4
PACKAGE COMPONENTS
Each Hardwired Timer AC4 package includes:
1 - 3850B Timer AC4 Console Unit
2 - IR Beam Emitters (5040)
2 - IR Track Sensors (5140)
2 - Track Sensor Cables - 100ft each (05-3811)
1 - Power patch cord 6ft (6510B)
1 - Owners Manual
Each Wireless Timer AC4 package includes:
1 - 3850BW/BZ Timer AC4 Console Unit
2 - T-Link3 modules (IDs A/B)
- 900Mhz Domestic USA (5840AW)
- 2.4 Ghz Interntional (5840AZ)
2 - IR Beam Emitters (5040)
2 - IR Track Sensors (5140)
2 - Track Sensor Cables (05-5825)
1 - Power patch cord 6ft (6510B)
1 - Owners Manual
POWER REQUIREMENTS
You will need these additional items to operate
your Timer AC4:
3850 Console 12.6VDC-3A reg.
PRODUCT SPECIFICATIONS
The following listing provides the designed
performance specs for the 3850 Timer AC4:
Start/Finish Lane Width 4 to 50 Feet
Timer Capacity (m.ss.f) 9:59.999
(sss.f) 999.999 sec
Time Accuracy 0.001 seconds
Model 5840 T-Link3
Frequency 900MHz band
Battery (pn 55-E670) USB Lithium-Ion
Battery Pack
T-Port Connections 05-5825 to Sensor
Connection Type RJ45 Modular
Identier Codes A-B to sensors
Max Operating Range -20ºF to 120ºF
Model 5840 T-Link3
Frequency 2.4GHz band
Battery (pn 55-E670) USB Lithium-Ion
Battery Pack
T-Port Connections 05-5825 to Sensor
Connection Type RJ-45 Modular
Identier Codes A-B to sensors
Max Operating Range -20ºF to 120ºF
.
AVAILABLE OPTIONS
06-58AX Recongure kit for T-Links
6070B Carry/Storage Case
6502A AC Power Adapter (Timer ONLY)
5050 Extended range Beam Emitter - 75 ft
7540 Foam Stands (for sensors & emitters)
6860/6650 Digital Displays
4520/4620 Wireless Data Comm Links (for
displays > 100ft from the console)
6033A Serial data 3850 to PC (9-Pin D-sub)
45232A Serial data 3850 to PC USB
THEORY OF OPERATION
The Model 3850 Timer AC4 is a completely
self contained race timing system made with the
latest technology CMOS circuit components
to provide a highly accurate autocross timing
solution. The system contains an internal quartz
crystal clock to maintain time accuracy and display
of race results to one thousandth of a second.
The AC4 can operate with a single sensor
(lap timer) or with dual location Start/Finish
sensors. The system can receive data from either
wireless track sensors (T-Links), hard-wired track
sensors or manually from the console keypad.
Desired settings are selected in a conguration
menu and retained until changed at a later time.

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RaceAmerica Model 3850 Timer AC4
Keypad functions for each mode are described
in this manual.
SET-UP STEPS - WIRELESS TIMER
Place the ‘A’ unit at the Start and the ‘B’ unit
at the Finish per diagrams (Fig 4 or 5). Positioning
the antenna(s) as high in the air as possible will
optimize performance.
Power on a T-Link and observe the LED
illuminates alternating between red and green, .
If the battery charge is at minimum charge, the
T-Link will power o even if the power switch
is ON. When T-Links are powered on, the LED
will ash green when a wireless signal is received.
During normal operation, the LED on each T-Link
will ash red during transmit and ash green each
time signal is received from another T-Link.
The *4 CONFIG menu in Fig 11 is used
to configure the timer for single/dual sensor
operation, minutes/seconds display, sensor lockout
times, printer conguration and timslip header
printing. See the full CONFIG properly set up
and aligned on the racing surface, the timer console
will continue to ‘monitor’ the track sensor at the
start line to start the next timer or at the nish line
to stop the next timer (lap-timer uses only the start
beam).
NOTE: once the start or nish line beam
is interrupted, the system imposes a two to nine
second lockout (see CONFIG menu) of that sensor
to allow blowing debris to settle. During the
last second of the lockout, the system performs
alignment testing of the triggered sensor to
determine if the alignment has changed. Failure
of the starting line beam alignment is indicated
by ashing [StArt] [SEnSor] [test] [fAiLEd].
[Finish] [SEnSor] [tESt] [FAiLEd] would
indicate the nish line alignment has failed testing.
These messages are displayed until another
message updates the Status Display. This feature
helps in early detection and resolution of a low
battery in the Beam Emitters, someone tripped
over a cable, or a sensor has been bumped out of
alignment.
NOTE: Once all four timers are actively
counting, any additional interruption of the start
line beam will not start a new timer until one of the
current timers is stopped by a nish line crossing
or manually stopped via the keypad (Wired only).
Install the antennas on all T-Link units. If the
antenna has been bent down for transport, loosen
the antenna slightly and rotate the upper portion
of the antenna into position. Hold the upper
portion of the antenna while tightening the knurled
area on the bottom portion of the antenna. The
antenna should point in the vertical direction and
be o the ground by eight to ten feet for optimal
performance.
STEP 1 -
Familiarize yourself with the Components
pictured in this manual and how they interconnect.
Track Sensor Cables are used to connect the
starting line and nish line to the timer console
or T-Link Wireless units (Fig. 1 thru 6).
All connectors are keyed for proper
orientation. The 12VDC battery is connected
with the RED alligator clip to plus (+) terminal
of the battery and the BLACK alligator clip to
(-) terminal of the battery. Do not connect to an
operating motor vehicle! Optional 110/230VAC
adapters can also be used instead of a battery.
The free standing, battery powered Model
5040/5050 IR Beam Emitters are placed on the
end of the start line and nish line away from
the timer console and the Model 5140 IR Track
Sensors are placed on the console side of the start
line and nish line. Each of the Beam Emitter and
Track Sensor units are fully interchangeable with
each other. The Track Sensor cables plug into
their respective start and nish connectors on the
underside of the console.
If the T-Link Wireless option is used to
connect the track sensors, follow set-up per the
diagrams (Fig 3 or 5).

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RaceAmerica Model 3850 Timer AC4
STEP 2 -
Identify the emitter/sensor placement at the
common start/nish line (laptimer) or the start line
and nish line (autocross Solo II). The lane width
should be set between four (4) and fty (50) feet
for 5040 and eight (8) and seventy-ve feet for
5050 emitters. To help in determining initial Beam
Emitter to Track Sensor alignment in larger track
widths, use a string stretched between the beam
emitter and track sensor or eyeball a straight line
between units.
STEP 3 -
Layout the wireless links or cables on the
track site. The large connector (RJ45) connects
to the console or T-Link Wireless unit and the
smaller connectors (RJ11) connect to the Track
Sensors at the start line or the nish line.. Connect
the Cable(s) to the Timer Console and the Track
Sensors. Single sensor laptimers use only the start
sensor position.
Once the system is properly set up and
aligned on the racing surface, the timer console
will continue to ‘monitor’ the track sensor at the
start line to start the next timer or at the nish
line to stop the next timer (lap-timer uses only
the start beam).
NOTE: once the start or nish line beam
is interrupted, the system imposes a two to nine
second lockout (see CONFIG menu) of that sensor
to allow blowing debris to settle. During the
last second of the lockout, the system performs
alignment testing of the triggered sensor to
determine if the alignment has changed. Failure
of the starting line beam alignment is indicated
by ashing [StArt] [SEnSor] [test] [fAiLEd].
[Finish] [SEnSor] [tESt] [FAiLEd] would
indicate the nish line alignment has failed testing.
These messages are displayed until another
message updates the Status Display. This feature
helps in early detection and resolution of a low
battery in the Beam Emitters, someone tripped
over a cable, or a sensor has been bumped out of
alignment.
STEP 4 -
Connect any optional scoreboards, displays
or PCs per owner manuals at this time. The
drawings in Figs 6 thru 8 show some of the
connection options. The Printer RS232 port can
be recongured to a RS232 Display port in the
Conguration menu.
Connections are for RS232 serial data at
9600 baud. When the option is located more than
100ft from the console, using wireless or RS422
communication PODs will accomplish the task.
STEP 5 -
Connect the RED and BLACK alligator clips
to the 12VDC battery or 110/230 VAC AC Adapter
and you’re ready to begin.
POWER ON/SELF-TEST
Connecting the 12VDC power source places
the RaceAmerica Timer AC4 into a self-test of the
microprocessor circuitry and LED displays (Light
Emitting Diode). This is an internal test as well as
a visual check of each display. The four line dis-
play sequences an [8] digit through each segment
of all lines. The four line display then sequences
through the product number and the code revision
level coned within the timer.
At the end of the power-up sequence, the
system automatically detects which mode is se-
lected making the available displays and functions
available.
When the sensor(s) are hard wired and ON,
one column of dots at the right edge of each dis-
play line will ash periodically if they are properly
aligned.
When the AC4 unit is ON and an antenna is
connected to the timer, one column of dots at the
right edge of each display line will double ash
periodically.
SYSTEM SETTINGS
Press *1 REPORT to print the current
systems setup to a connected printer. This is very
helpful to quickly see if the system is congured
as desired.

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RaceAmerica Model 3850 Timer AC4
Power
Blink RED/GREEN - Power ON
LED Information
RF Receive Status
Blink GREEN - Receive
Blink RED - Transmit
Align Status
Solid RED - Not aligned
ID Code
e.g. ‘C’
Optimizer Code
e.g. C305
Figure 1 - T-Link3 power and external connections
WARNING: To avoid damage to wireless
units, do not operate any wireless device without
the antenna installed. Do not operate wireless
units within four feet of each other
The *4 CONFIG menu is used to congure
the timer for single/dual sensor operation, minutes/
seconds display, sensor lockout times, printer
conguration and timslip header printing. See
the full CONFIG menu in Fig. 10.

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RaceAmerica Model 3850 Timer AC4
Fig 2 - Laptimer hard-wired;
plug into START
Fig 3 - T-Link wireless Laptimer
Track Sensor
Laptimer Single Track Sensor
Conguration

10
RaceAmerica Model 3850 Timer AC4
Fig 4 - Hardwired Track Sensors
Fig 5 - T-Link wireless with
external Track Sensors
Dual Track Sensor Conguration

11
RaceAmerica Model 3850 Timer AC4
CONSOLE
DIGITAL DISPLAY
DIGITAL DISPLAY
12VDC
06-X025
25FT CABLE
4520 LINK
12VDC
12VDC
ST
FIN
TLNK
PRNT
CONSOLE
DIGITAL DISPLAY
DIGITAL DISPLAY
12VDC
07-4554
1FT CABLE
07-4554
1FT CABLE 06-X010
10FT CABLE
07-3434
CABLE
07-3434
CABLE
4500 COMM
POD
4500 COMM
POD
4500 COMM
POD
12VDC
12VDC
ST
FIN
TLNK
PRNT
9VDC
Fig 6 - RS232 Hard wired
Digital Display and/or
PC. Limited to 100ft
cable lengths
Fig 7 - Hard wired Digital Displays
utilizing Communication PODs
Fig 8 - Wireless Digital Displays
Connecting System Options

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RaceAmerica Model 3850 Timer AC4
CONSOLE FEATURES
Fig 9 - The Timer AC4 Console contains a four line display for display of lap/run times, the
current mode of operation of the timer, comrms detection of a car by the Track Sensors, Emitter/
Sensor alignment and used for conguration menu promps and selections.
Keypad
Timer Displays
Connectors on bottom
CONFIGURATION MENU
The Timer AC4 Model 3850 oers exibility
in conguration and setup retention. Use the [*4]
CONFIG menu (Fig. 10) to select how the Printer
Port will be used (it can be congured as a Printer
port (Print) or RS232 Display port (diSP)). When
congured as a display port, other print settings are
ignored. To congure a printer to print timeslips
and a report of the conguration (*1 REPORT),
congure race parameters - single or dual sensor
(Laptimer or Start/Finish layouts). Select time
display format as sss.f (seconds and fractions or
m:ss.f (minutes, seconds and fractions); select a
maximum time for cars not nishing or cars taking
a longer time than allowed; select sensor lockout
times for start and nish sensors. Lockout times
can be two to nine seconds and represent the time
until a sensor will not see another trip to allow for
rear wheels and blowing dirt to settle. Use the
CONFIG menu to create a timeslip header of up
to 39 characters on four lines. Navigate the menu
using the [4] and [#] keys as shown in Fig. 10 and
described in the next section.
CONFIGURE PRINT HEADER
The AC4 allows a custom four line timeslip
print header of up to 39 characters per line when a
printer is connected. Input is accomplished using
character codes for each desired character position
(see work sheets). Press *444[CONFIG]. Press #
[ENTER] to view the setup dialog as follows [L1
C01] [ XXYY] indicating Line 1 Character 01;
the XX is prompting for the character code for the
desired character and theYY is the next chracter;
refer to the worksheet for the correct code, press
[#] to move to character 02 [L1 C02] [XXYYZZ]
where XX is Character 01 and YY is prompting
for character 02 and ZZ is character 03; continue
for up to all 39 characters in the line. Press [*] to
move to Line 2 [L2 C01] [ XX00] and continue
for all four lines. When done with all four lines,
press [#] ENTER to exit the conguration menu.

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RaceAmerica Model 3850 Timer AC4
ALIGNMENT MODE
Hard-Wired Sensor Alignment -
To verify hard-wired Track Sensor(s) are
properly aligned with their Beam Emitter(s), make
sure the sensor(s) are ON ([*2]). Enter the hard-
wired Alignment Mode by pressing the [*5] key on
the Keypad. The Status Display shows [SenSor]
[ALiGn] [S0--0F]. The [S] indicates the START
emitter/sensor pair, the [F] indicates the FINISH
line emitter/sensor pair. If the Beam Emitter and
Track Sensor are operating properly and aligned,
the 0 digit will not change. If the Beam Emitter
and Track Sensor are not properly aligned, the
0 digit for each emitter/sensor pair will count
slowly if slightly out of alignment or continuously
if they are not functioning properly or way out
of alignment. Once the emitter/sensor pair are
aligned properly, the digit will stop counting. If
the alignment is o a little or intermittent, the
digit for that emitter/sensor pair will count when
they oat out of alignment. Remember, the Beam
Emitters and Track Sensors operate on a ‘Line-of-
Sight’ concept and may require shims if they are
installed on a street with a crown. Leaves, people,
and other debris will also break the beams and
could give false signals, so keep everyone and
everything clear of the Beam Emitters and Track
Sensors during racing activity.
To optimize the alignment of the emitter/
sensor pairs, it is suggested to rotate the Beam
Emitter slowly left and right until the alignment
for that pair begins to count. This technique will
determine the maximum lateral detection angle.
Rotating the Beam Emitter up and down until
the alignment starts counting determines the
maximum vertical detection angle. Once these
extremes are established, position the Beam
Emitter in the center of the left/right detection
angle and up/down detection angle. Repeat this
same process with the other Beam Emitter and
both Track Sensors. This will maximize the
alignment accuracy. Press the [#] pound sign key
to exit Alignment Mode.
If the sensors are not ON, the display will
show [no] [ALiGn] [SEnSor] [OFF].
T-Link Sensor Alignment -
Proper alignment can be determined by
observing the Left LED on the T-Link connected
to the sensor. When the LED is blinking slowly,
the emitter and sensor are aligned; when the LED
is ON solid, the sensor is not properly aligned. Use
the same alignment technique discussed for hard-
wired sensors to attain correct alignment while
monitoring the LED status. Do this for both the
Start and Finish sensor if running in ‘dual’ sensor
mode. When T-Link sensors are connected, one
column of dots at the right edge of each display
line will double ash periodically.
SERIAL PORT CONFIGURATIONS
The RS232 Serial Port can be congured for
T-Link Wireless Track Sensors or to interface to
a PC running race management software.
The Serial Port is enabled for two way
communications (in for T-Link data, out for PCs
and displays. The Printer port is also a serial port
and can be recongured for a display..
NOTE: When connecting to the Serial Port,
the PC or display must be congured at 9600 baud,
8 data bits, no parity, 1 stop bit, no handshake
(9600/8/N/1).
RF INTEGRITY
When operating the Timer AC4 with
T-Link wireless sensors, the Radio Frequency
Signal integrity can be monitored. Pressing [*6]
on the keypad will cause connected T-Link units
to monitor the RF signal integrity indicated by [--
rF--] [A---X] [b---X]. ’X’ represents 0 for 0%, 1
for 10%, 2 for 20%, etc and a dash for 100%. ‘A’
sensor (Start), ‘B’ sensor (Finish) and ‘Z’ unit can
be seen on the display. Any reading above 30%
should be adequate for timer operation. This is an
indication of the consistency of the RF integrity.
If this number jumps around, there is a high level
of interference in the area. If the number remains
high, the RF signal strength is very good. If the
number remains low, the RF integrity is somewhat

14
RaceAmerica Model 3850 Timer AC4
ConFiG
Print
ConFiG
rACE
ConFiG
HEAdEr
LF XX
AutoPr X
[4]
[#]
[#]
[#]
[4]
[4]
SEnSor SinGLE
duAL
[4]
[#]
[#]
[4]
*4 CONFIG
LoG
Blank
Blank
3850 rev H.10
Conguration Parameters
--- Printer Settings
Printer Port Use Printer
Number of Line Feeds 10
Autoprint copies 1
Printed Format Timeslip
--- Race Event Settings
Sensors Enabled Start+Finish
Timing Format SSS.FFF
Maximum Time (auto end) 999.999
Default O Course Time 999.999
Start Sensor Lockout 5
Finish Sensor Lockout 5
--- Timeslip Header
3850 Timer AC4
4-timer Autocross Timing System
T-Link Wireless Enabled
L1 C01 to C39
XXXX
[#]
[#]
*
L2 C01 to C39
XXXX
[#]
*
L3 C01 to C39
XXXX
[#]
*
L4 C01 to C39
XXXX
[#]
*
[#]
[4] SLiP
SSS.f OFF
on
[#]
End ET xxx.xxx
[#]
out ET xxx.xxx
[#]
StArt SEnSor LocOut SEC
x
[#]
FiniSH SEnSor LocOut SEC
x
[#]
Blank
[4]
CONSOLE CONFIGUATION MENU
Fig 10 - System Conguration Settings
Menu, Press *4 [CONFIG];
settings are retained until changed
at a later time.
Conguration Parameters printout -
Press *1 (report) to send this summary of
current settings to a connected and compat-
ible printer.
Blank
[#]
Blank
[#]
[#]
diSP [4] Print

15
RaceAmerica Model 3850 Timer AC4
weak and data reporting may be slowed by retries
but will not alter the accuracy. The position of
the T-Links and their antennas can be moved to
optimize the RF Integrity level.
WIRELESS BATTERY LEVEL
When operating the Timer AC4 with T-Link
Wireless sensors, The battery level of each wireless
link unit can be monitored from the console. Press
and release the [*9] key to monitor the Battery
Level of the T-Links on the track indicated by
[-bAtt-] [A---X] [b---X] [Z---X]. ’X’ represents
0 for 0%, 1 for 10%, 2 for 20%, etc and a dash
for 100%. ‘A’ sensor (Start), ‘B’ sensor (Finish)
and ‘Z’ unit (internal) can be seen on the display.
Any reading above 50% should be adequate for
hours of operation.
TIMER OPERATION
Once set up, operation of the Timer AC4 is
very straight forward. Select from below which
setup matches your requirements:
Single Beam - Laptimer conguration
Manual operation
This manual stop-watch type operation works
with sensors ON as selected in SENSORS [*2].
and sensors aligned and connected or a fake sensor
jumper set installed.
Press START [3] each time a vehicle crosses
the Start/Finish line, any running timer will stop
countiing and a new one will start counting. After
each nish/start, a lap number is assigned to each
start on the console (press/hold [0] to view lap
number; press/hold [8] to view the ‘Best’ lap).
Each nish freezes the running timer and
sends the time to the serial ports (PCs and
displays).
If a car goes o course and cannot nish;
press ‘Did not Finish’ DNF [9] when the car
should nish and their time will be set to the time
congured in [out Et] (*44####).
If a car reaches the maximum time allowed,
its timer will automatically stop at that number.
This time is congured in [End Et] (*44###).
Use ‘All Stop’ [*7] to stop all currently
counting timers when something happens
requiring a rerun of all cars on the track.
Single Beam - Laptimer conguration
Hard-Wired
Run Single Beam hard-wired with Sensors
[on] as congured in SENSORS [*2] and the cable
in the START connector. Each time the beam is
interrupted, a timer will stop countiing and a new
one will start counting. After each nish/start, the
beam is locked out for two to nine seconds (see *4
CONFIG) to allow the car to pass through and the
dust to clear. A lap number is assigned to each start
on the console (press/hold [0] to view lap number;
press/hold [8] to view the ‘Best’ lap).
Each nish freezes the running timer and
sends the time to the serial ports (PCs and
displays).
The console operator can use the Manual
Start [3] key to over-ride the track sensor or
when the Status Display indicates the sensors are
disabled [*2].
If a car goes o course and cannot nish;
press ‘Did not Finish DNF [9] when the car
should nish and their time will be set to the time
congured in [out Et] (*44####).
If a car reaches the maximum time allowed,
its timer will automatically stop at that number.
This time is congured in [End Et] (*44###).
Use ‘All Stop’ [*7] to stop the currently
counting timer to reset for another car.
During timing, alignment status can be
checked.
Sensor status is monitored in the background.
When the sensors are properly aligned, the decimal
points by the rightmost character on each line will
ash intermittently (about every three seconds). If
the start sensor goes out of alignment, the display
will show [StArt] [SenSor] [test] [FAiLEd] with
‘test failed’ ashing to get the operators attention.
Unaligned sensors will cause a sensor trip and
a sensor trip each lockout interval as set in the

16
RaceAmerica Model 3850 Timer AC4
CONFIG menu (*44#####). During an out of
alignment situation, turn o the sensors and use
the manual START (3)/FINISH (6) to continue
the event.
Single Beam - Laptimer conguration
T-Link Wireless
Run Single Beam Wireless with Sensors
[OFF] as congured in SENSORS [*2]. Each time
the beam (T-Link ‘A’) is interrupted, a timer will
stop counting and a new one will start counting.
After each nish/start, the beam is locked out for
two to nine seconds (see *4 CONFIG) to allow
the car to pass through and the dust to clear. A
lap number is assigned to each start on the console
(press/hold [0] to view lap number; press/hold [8]
to view the ‘Best’ lap).
Each nish freezes the console and sends the
time to the serial ports (PCs and displays).
If a car goes o course and cannot nish;
press ‘IGNORE [2] to not count the lap. Use ‘All
Stop’ [*7] to stop the currently counting timer to
reset for another car.
This mode only operates with ‘SENSORS’
OFF ([*2]).
During timing, status conditions can be
checked. RF Integrity and Battery Level status
are available. Alignment status is available on the
‘A’ T-Link Wireless unit.
Dual Beam - Autocross Solo II
Manual
This manual stop watch type operation works
with Sensors [OFF] as selected in SENSORS [*2].
and sensors aligned and connected or a fake sensor
jumper set installed.
When a vehicle cosses the Start line, press
‘Start’ [3], a timer will start countiing. When a
car crosses the Finish line, press ‘Stop’ [6] and the
rst running timer will stop. Up to four cars can
start before the rst car must nish. Once a car
has nished, another car can start. A run number
is assigned to each start on the console. Cars must
start and stop without passing.
Each nish freezes the highest count running
timer and sends the time to the serial ports (PCs
and displays) until another run starts.
If a run is stopped in error, the operator can
press Continue [5] which will restart the last run
stopped. This feature can restart timers for all runs
on the display without losing any time.
If a car goes o course and cannot nish;
press ‘Did not Finish DNF [9] when the car
should nish and their time will be set to the time
congured in [out Et] (*44####).
If a car reaches the maximum time allowed,
its timer will automatically stop at that number.
This time is congured in [End Et] (*44###).
Use ‘ALL STOP’ [*7] to stop all currently
counting timers when something happens requiring
a rerun of all cars on the track. Run numbers are
not reset. Alternately, ‘RESTART’ [*0] will reset
the timer to the initial power-up settings.
Dual Beam - Autocross Solo II
Hard-Wired
Run Dual Beam hard-wired with Sensors [on]
as congured in SENSORS [*2] and the sensor
cables in the START and FINISH connectors.
Each time the Start beam is interrupted, a timer
will start countiing. After each start, the beam
is locked out for two to nine seconds (see *4
CONFIG) to allow the car to pass through and
the dust to clear. Up to four cars can start before
the rst car must nish. Once a car has nished,
another car can start. A run number is assigned
to each start on the console. Cars must start and
stop without passing.
Each nish freezes the highest count running
timer and sends the time to the serial ports (PCs
and displays) until another run starts.
The console operator can use the Manual
Start [3] and or Manual Stop [6] keys to over-ride
the track sensors.
If a run is stopped in error, the operator
can Continue [5] which will restart the last run
stopped. This feature can restart timers for all runs
on the display without losing any time.

17
RaceAmerica Model 3850 Timer AC4
If a car goes o course and cannot nish;
press ‘Did not Finish DNF [9] when the car
should nish and their time will be set to the time
congured in [out Et] (*44####).
If a car reaches the maximum time allowed,
its timer will automatically stop at that number.
This time is congured in [End Et] (*44###).
Use ‘ALL STOP’ [*7] to stop all currently
counting timers when something happens requiring
a rerun of all cars on the track. Run numbers are
not reset. Alternately, ‘RESTART’ [*0] will reset
the timer to the initial power-up settings.
While timing cars, Alignment status can be
checked without losing a timed run.
Sensor status is monitored in the background.
When the sensors are properly aligned, the decimal
points by the sixth character on each line will ash
intermittently (about every three seconds). If the
start sensor goes out of alignment, the display will
show [StArt] [SenSor] [test] [FAiLEd] with test
failed ashing to get the operators attention. If the
nish sensor goes out of alignment, the display
will show [FiniSH] [SenSor] [test] [FAiLEd] with
test failed ashing to get the operators attention.
Unaligned sensors will cause a sensor trip and
a sensor trip each lockout interval as set in the
CONFIG menu (*44#####). During an out of
alignment situation, turn on Sensors (*2) and
use the manual FINISH (6), CONTINUE (5) and
START (3) may be used with a fake sensor jumper
set installed.
Dual Beam - Autocross Solo 1
Wireless
Run Dual Beam Wireless with Sensors [OFF]
as congured in SENSORS [*2]. Each time the
start beam (T-Link ‘A’) is interrupted, a timer will
start countiing. After each start, the beam is locked
out for two to nine seconds (see *4 CONFIG)
to allow the car to pass through and the dust to
clear. Up to four cars can start before the rst car
must nish (T-Link ‘B’). Once a car has nished,
another car can start. A run number is assigned
to each start on the console. Cars must start and
stop without passing.
Each nish freezes the running timer and
sends the time to the serial ports (PCs and displays)
until another run starts.
If a car goes o course and cannot nish;
press ‘Did not Finish DNF [9] when the car should
nish and their time will be set to the maximum.
Use ‘ALL STOP’ [*7] to stop all currently
counting timers when something happens requiring
a rerun of all cars on the track. Run numbers are
not reset. Alternately, ‘RESTART’ [*0] will reset
the timer to the initial power-up settings.
While timing cars, status conditions can be
checked. RF Integrity and Battery Level status are
available. Alignment status is always available on
the ‘A’ and ‘B’ T-Link Wireless units.
COUNTDOWN TIMER
The AC4 has a separate countdown timer to
be used for timed breaks in the action. To activate,
stop all timers [*7]. Press COUNT [1]; the display
will show [EntEr] [StArt] [XX] displays; enter
the number of minutes (01 to 99) and press #
ENTER. The display will show [Count] [XX.
XX] representing minutes and seconds remaining.
Press [1] again to stop the count; [StoP] [Count]
will briey display and the screen will blank. The
count is sent to any LED displays connected to
the AC4.

18
RaceAmerica Model 3850 Timer AC4
Fig. 11 Keypad
KEYPAD FUNCTIONS
The 3850 timer utilizes a second function keypad;
functions printed in white operate when pressed;
functions printed in yellow require the ‘SHIFT’
button to be pressed two seconds before the desired
second function yellow key is pressed.
The following denes the keypad key functionality:
Each function is coded for which modes it is
available in as follows:
Manual mode •
Hard wired mode •
T-Link Wireless mode •
KEY 1 •••
Pressing 1 COUNT will allow the timer to go
into countdown mode: [EntEr] [StArt] [XX]
displays; enter the number of minutes (01 to
99) and press # ENTER. The display will show
[Count] [XX.XX] representing minutes and
seconds remaining. Press [1] again to stop the
count; [StoP] [Count] will briey display and
the screen will blank.
KEY 2 •••
The 2 IGNORE key will stop and give no time
for the currently running timer.
KEY 3 ••
Pressing the [3] key will manually start a timer.
This is the same function as breaking the start
beam. This key is enabled when sensors (KEY 2)
are [ON] and a timer is running. If all four timers
are counting and the [3] key is pressed, the bottom
timer will be lost and a new timer will be started at
the top of the display. Since this is manual mode,
the operator has full control of the timer starting
function.
KEY 5 •••
If a timer is inadvertently stopped by a worker
running through the nish line or manually stopped
by pressing the Manual Stop or O Course keys,
the timer can be restored and counting with the
correct elapsed time using the [5] Continue key.
The most recently stopped timer is restarted and
updated from a backup timer internally maintained
by the Timer AC4. The timer is restarted and
updated with the correct elapsed time. A timer
can be stopped and restarted an unlimited number
of times.
NOTE: All four timers also have a backup timer
internally maintained by the Timer AC4. These
free-running timers do not stop at the maximum
elapsed time, instead, the timers roll over back to
zero and continue to count. Care should be taken
if a long period of time elapses between when the
timer was stopped and restarted.

19
RaceAmerica Model 3850 Timer AC4
KEY 6 ••
To manually stop the next timer, press the [6]
FINISH key. This is the same function as a car
crossing the nish line and blocking the beam.
This key is enabled when sensors (KEY 2) are
[ON] and a timer is running. Stoping a timer
indicates [FiniSh] in the timer window..
KEY 8 •••
To review the ‘BEST’ time or lap, press and
hold [8].
KEY 9 •••
If a car does not complete the course and their
time is no longer valid, wait until their timer is the
next timer to stop. Pressing the [9] [DNF] key will
stop the next timer (same as the car crossing the
nish line) and update the timer with the maximum
elapsed time to indicate the car went O Course
and the time is invalid. The maximum value can be
congured in [*4] CONFIG; 9:59.999 or 999.999
seconds dependent upon the Timer AC4 display
format ordered are the maximum times.
KEY 0 •••
To review the last four run or lap numbers,
press and hold [0] RUN/LAP.
KEY # •••
Use the [#] ENTER key to accept input data
and navigate the CONFIG menu.
KEY *1 •••
Pressing *1 will print the current conguration
in he system to a connected serial printer. See
sample. Use *5 CONFIG to make changes.
KEY *2 •
The [*2] key is used to toggle hard-wired track
sensors [-on-] (enabled) and [OFF-] (disabled).
NOTE: If the T-Link Wireless unit is
connected and powered on, the [0] key is disabled.
NOTE: When the sensors are in either mode,
they will not detect any cars crossing the start or
nish line in the other mode.
KEY *4 •••
Press [*4] to enter the CONFIG menu. See
separate Fig. 11 to see all the details of the system
conguration menu.
KEY *5 •
To enter alignment mode, for hard wired
sensors, press the [*5] keys on the keypad; sensor
alignment at the start and nish lines indicated by
[-SF-] displayed. The left dash is the start line and
the right dash is the nish line. The dashes will be
replaced by a number. The sensors are checked
continuously and the display is updated 4 times
a second. If the sensor is aligned, the number
will not change. If the sensor is intermittently
out of alignment or on the edge of alignment, the
corresponding number will count intermittently. If
the sensor is out of alignment, the corresponding
number will count 4 times a second.
KEY *6 •
Pressing [*6] on the keypad will cause
connected T-Link units to monitor the RF signal
integrity. The display will show [-rF-]. The
left dash is the start line and the right dash is the
nish line. The dashes on the display will begin
to count up as signals are received from the T-Link
units on the track. 0 displayed represents 0%, 1
represents 10%, 2 represents 20% etc. until a dash
appears representing 100%. This is an indication
of the consistency of the RF signal integrity. If
this number jumps around, there is a high level
of interference in the area. If the number remains
high, the RF signal integrity is very good. If the
number remains low, the RF signal is somewhat

20
RaceAmerica Model 3850 Timer AC4
weak. The position of the T-Links and their
antennas can be moved to optimize the RF
Integrity level.
KEY *7 •
Pressing [*7] on the keypad will halt all
currently counting timers. This is convenient
when something happens on the track requiring a
restart of all cars being actively timed. The next
run will be assigned the next Run Number when
the start beam is interrupted.
KEY *0 •••
Pressing the [*0] key halts all timers, resets
all four timers back to 0.000 seconds, clears the
run numbers, and resets the next run number to
01. This function is used to completely reset the
Timer AC4 back to its initial startup point.
KEY *8 •••
Pressing *8 will RESTART the timer and reset
the run/lap numbers and best times.
KEY *9 •
Pressing *9 will display T-Link battery levels
as follows: [-bAtt-] [A---X] [b---X] [Z---X] where
‘X’ is the relative charge (1 to 9 plus - (100%)).
If you press *9 when no T-Links are not connect-
ed, the display will show[no rF] [SEnSor] [on].
STATUS DISPLAY MESSAGES
During normal operation, messages will
appear in the Status Display. These messages
indicate status, mode of operation, or events
occurring on the race track. Many of these
messages are covered elsewhere in this manual and
are alphabetically summarized in the following
section as a reference:
Align -SF-
When entering Alignment Mode, these
messages will appear in sequence to indicate the
alignment of the Track Sensors and Beam Emitters
will be continuously monitored and the results
displayed.
on
This display indicates the AC4 is operating in
the hard wired mode and track sensors are enabled.
no ALiGn SEnSor on
This message appears if *5 is pressed when the
sensor(s) are ON. Press *2 to turn the sensor(s)
OFF so alignment can be checked.
FiniSh SEnSor tESt FAiLEd
This message appears during the power-up
sequence and indicates the software code level
running in the RaceAmerica timer.
iGnorE
Pressing the [2] Ignore key will ignore he last
sensor trip; either Start or Finish.
OFF
This message will keep appearing if the
sensors have been disabled by the operator. This
message is a reminder to enable the sensors prior
to the start of the race event in order to detect cars
at the start and nish lines. This message will also
appear if the T-Link Wireless is disconnected or
powered o.
Out
This message will appear when the operator
determines a car has strayed o course and the
respective timer in the Timer Display is no longer
valid. The timer in the Timer Display currently
counting with the highest time elapsed is stopped,
set to the maximum time value, and output is sent
to the printer.
StArt SEnSor tESt FAiLEd
This message indicates the alignment of the
Track Sensor and Beam Emitter at the start line