Vantec KH716 User manual

OVERVIEW: The KH712, KH716 and KH732
Hitchiker Radio Control systems combine Futaba's
excellent PCM1024 radio systems with VANTEC
KeyKoder technology to add the extra channels and
functions needed for Special EFX projects,
inspection/sample harvesting vehicles, and tele-
operated robots. Great for controlling submarines
with their complex plumbing and pumps. Making
your dream scale R/C boat fully operational is now
easier than ever. Eliminate fussy servo-
microswitch kluges. Microprocessor equipped
projects have used the Hitchiker channels to initiate
pre-programmed routines. Available on 72 or 75
MHz frequencies; there is no additional charge to
have your transmitter legal. VANTEC warrantees
the entire system.
The three systems are complete including the
Futaba FP7CAP series radio control sets and come
with transmitter, receiver, selection of servos, Nicad
batteries, charger and the VANTEC Hitchiker
KeyKoder components. The Futaba radio sets are
top-of-the-line models using Futaba's PCM1024
Pulse Code Modulation method. PCM is a
significant improvement over FM because it
transmits the servo commands as digital words with
special mathematical properties that facilitate
accurate reception and calibrated servo positions for
Fail Safe operation. Servo jitters are a thing of the
past. The F/S meets the criteria for competitive
robot safety shut-down. See the side panel for more
about the PCM Advantage.
VANTEC fully harnesses Futaba's coding to
reliably pack additional controls onto one of the
Futaba R/C servo channels. The new controls are
independent and operate simultaneously. The
remaining conventional channels are not affected.
To make a complete Hitchiker system VANTEC adds
two devices to the Futaba set.
The first device is a KeyPad that is added to the
transmitter. It mounts onto the base of the Futaba
FP-7CAP transmitter. Each new KeyPad channel is
actuated by a special toggle switch that can operate
momentarily like a push button by pressing down; it
automatically springs back to center off. Or switch
it "On" continuously like a normal toggle switch by
flipping it up. Any number of switches may be
activated at once. The KeyPad switches are labeled
1-16 or 1-32. The KeyPad understands and "speaks"
PCM1024; it interjects its new data onto one of the
regular servo channels through the trainer
connector. This means you lose the normal
operation of the selected channel; usually the
invisible 8th channel of the 7 channel system or the
"Retract" channel 5 is sacrificed.
The second device is a Receptor add-on box that
plugs into the Futaba R/C receiver like a servo and
separates the KeyPad commands back into 12, 16 or
32 individual outputs corresponding to the
transmitter KeyPad switches. The Futaba receiver is
optically isolated from the workings of the
Receptor. The Receptor has terminal blocks and
MANUAL
Help:
(541) 471
-
7135
KeyKoder Radio Control Systems
Hitchiker
HitchikerHitchiker
Hitchiker Add-on channels to Futaba R/C

KH732
COMPLETE
39 Channel System
KH716 COMPLETE 23 Channel System
KH712 COMPLETE
19 Channel Aircraft
System
7 or
8 Proportional Servo Channels for servos
or Speed Controls plus....
16 or 32 Independent and Simultaneous ON-
OFF channels as 0-30V 5A Switches and
6 Two Position Servo Command Outputs and
2 Three position Servo Command Outputs
Featuring Reliable Futaba PCM1024 Radios

Available on 75MHz Surface vehicle
frequencies or 72 MHz Aircraft frequencies
VANTEC HITCHIKER R/C
vantec.com Phone: [phone] FAX: [phone] Honeycutt Dr., Grants Pass, OR 97526 0410

additional servo connectors
for the newly added
channels. These on-off or
two-state outputs manifest
themselves several ways
depending upon the
Receptor model. At 5A
capability each the ON-OFF
electronic switches can be
used directly for many
functions even with devices
operating on an assortment
of voltages. And the 8
conventional Servo Com-
mand Pulse outputs are a
handy and familiar way to
implement mechanical
functions using conventional
servos.
The KH716 complete
system has 7 conventional
servo channels and 16
independent and
simultaneous KeyKoder
ON-OFF electronic switch
channels for 23 channels total. The first 8 of the 16
KeyKoder channels coincidentally features 2 three-
position regular Servo Command Pulse outputs and
6 two-position regular SCP command outputs. The
KH716 system consists of: the complete Futaba
FP7CAP R/C set with the 7 channel FPR168DP or
other equivalent Futaba Brand receiver, VANTEC
KH16T KeyPad and KH16R Receptor and 2
servos. Additional servos available.
The KH732 complete system has 7 conventional
servo channels and 32 independent and
simultaneous KeyKoder ON-OFF switch channels
to yield 39 channels total. The first 8 of the 16
KeyKoder channels coincidentally feature 2 three-
position regular Servo Command Pulse outputs, 6
two-position regular SCP outputs. The KH732
systems consists of: the complete Futaba FP7CAP
R/C set, with the 7 channel FPR168DP or
equivalent Futaba brand receiver, VANTEC
KH32T KeyPad and KH32R Receptor and 2
servos. Additional servos available.
Generally the ‘716 & ‘732 versions are employed in
boats and robots. Up to 128 ON-OFF channels can
be added to a single Futaba Servo Channel with an
array of KeyKoders.
The KH712 is specifically configured for model
aircraft applications. Switches 1 through 8 on the
KH16T KeyPad generate only Servo Command
Pulses and switches 13, 14, 15, and 16 are the only
electronic switch outputs on the KH12R Receptor.
The KH712 Hitchiker is perfect for 1/4 scale R/C
model airplanes with 7 conventional servo
channels for the normal flying functions and 12
added KeyKoder channels for a total of 19
channels. It's KeyKoder Receptor features 2 three-
position regular Servo Command Pulse outputs, 6
two-position regular servo command outputs, and 4
electronic switches. Since the servo command
outputs are just like the signals coming from a
Futaba receiver you can plug-in up to 8new
conventional servos for auxiliary functions like
bomb bay doors, bomb release, or parachutists. The
electronic switches can be used to control engine
ignition, starting, lights and camera. The KH712
system consists of Futaba FP7CAP PCM R/C set
with an 8 channel receiver, VANTEC KH16T
KeyPad and KH12R Receptor and Servos.
TRANSMITTER / KEYPAD INSTALLATION:
The KeyPad is factory mounted to the Futaba case,
a slight modification made to the transmitter. You
cannot use the original trainer feature after these
modifications.
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KH716R & KH732R RECEPTOR
INSTALLATION: Keep all output wiring
separated from the Futaba receiver and servo leads. Use
the full extended length of the supplied receiver antenna
and locate it away from all other wires and metal
structures. Plug the Receptor add-on box into the Futaba
R/C receiver channel engraved "K", usually Futaba
channel 5. FPR168DP and FPR138DP receivers ordered
from VANTEC for KeyKoder applications have a small
internal modification to supply the needed signal out the
"K" marked channel. It is the same as the "C" or “DSC”
connector available on other Futaba PCM1024
receivers. Do not plug a servo into this channel as it will
disable all channels.
Some receivers like the FP-R129DP come with a "C" or
“DSC” output; plug the Receptor into this socket
regardless of the Futaba channel sacrificed for the
Hitchiker.
Receptor Servo Command Pulse outputs work in
conjunction with KeyPad channels 1-8. With KH16R
and KH32R receptors these SCPulse outputs operate
together coincidentally with ON-OFF outputs 1-8. These
Servo Command Pulse outputs are limited to two or
three fixed pre-determined positions and can drive
regular R/C servos or speed controls. Regular 3 pin plug-
in servo connections are provided on the Receptor in
three groups, each group accepting 3 servo connectors
netting 9 Futaba "J" style connectors in all. The 9th
position labeled "Bat", on the far right, is the power input
to run the 8 Receptor servos. A separate 4.8V battery
pack or suitably robust 5V regulator for this is
recommended.
Servo Command Pulse outputs "1-2" and "3-4" are the
three position servo outputs. Logically 2 switches on the
KeyPad are required to define 3 positions (4th
possibility not used). Further, the two and three
positions are designed so that a three position servo
output shares a transmitter KeyPad switch with a two
position servo output. For example: KSw1 controls
servo SCP1 which operates as two position actuator. But
KSw1 also commands the second SCP2 servo, along
with KSw2, for one of three positions. In practical
situations either 2 two-position servos OR 1 three
position servo would be deployed. The actual servo
positions are assigned in groups to provide a variety of
combinations as delineated in Fig 5. The three positions
are adjustable by three factory set and secured trimming
potentiometers.
Receptor ON-OFF Switch outputs are each capable of
current sinking to ground 0-30 VDC@ 5 amps. This
means they switch to ground to complete the circuit to
operate your device. Because they switch to ground they
easily accomodate a variety of lights, horns, motors and
other loads operating on a variety of voltages up to
30VDC by simply using different batteries or taps on a
series connected set of batteries. See Figure 1 above for
examples. Total continuous "box" current controlled at
any one time should be limited to 20 Amps.
Inductive coil loads like motors and relays inherently
generate a potentially damaging voltage spike when they
are turned off. We recommend the addition of a Metal-
Oxide-Varistor (MOV) across each inductive load to
safely suppress this spike. VANTEC has supplied a
number of MOVs with your Hitchiker. They are un-
polarized so you may connect them without regard for
position or orientation.
Figure 2 shows a simple "lossy" bridge circuit for
forward and reverse momentary operation of a small
motor such as the zoom and focus motors found in some
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video cameras. The resistors provide automatic current
limiting and un-equal resistor values can be used for
different forward and reverse speeds. Experimentation is
required but for a 12V battery bridge resistors should be
greater than 15 ohms; 24V battery - 30 ohms. Put a
MOV across the motor brushes.
To maintain satisfactory R/C operation select quality
motors whose RFI qualities are known from past R/C
applications. Some situations may require RF chokes in
series. Don't use toy motors with metal brushes or
automobile-type horns because these devices generate
horrific RFInterference.
Relays may be used to amplify the current capacity or
provide handy operating logic such as reversing high
current motors. Use MOVs across their contacts to
minimize RFI as well as in parallel across the coil for
spike suppression. Additional MOVs are available from
VANTEC or Radio Shack. Use AC types rated for 30-50
volts such as Panasonic ERZ-V05D390.
Figure 3 shows efficient operation of reversing motors
up to 5 amps using a single 5 amp relay and 5 amp diode
from Radio Shack. If your application runs into a
physical stop use the limit switches shown to prevent
dangerous stalled motor operation. For limit switch
installations you can have automatic reverse/return by
connecting wire "REV" to ground instead of a Receptor
output, omit diode, (saves a KeyKoder channel too).
Don't forget the MOVs.
Figure 4 shows the use of relays to operate much larger
motors, over 4 amps. In this circuit the limit switches
need only be capable of handling the relay coil current.
Use MOVs.
If the Receptor fails to receive KeyPad signals it uses the
old information for a brief time and then enters a fail safe
mode. In the fail safe mode all electronic switches are
turned off except KCh14 & 15 which maintain their last
state. You could use KCh14 to command lighting since
your vehicle could be at rest but illuminated with the
transmitter turned off; great for preventing runway
collisions at night or dinner flotillas.
KH16R and KH32R Receptor power wiring is through
the 18 station plug-in terminal block. The ground circuit
which supports these electronic switches-to-ground must
be substantial since all the current for all of your loads
passes through it; up to 5 Amps for each one. Use a
suitable gauge for the ground wire to support your switch
loads; AWG#16 for the full capacity. The ideal power
supply for the unit is +12VDC connected to the +
terminal of the terminal block .+. The power input
range on the + terminal may by 4.8-30VDC. When
power is not supplied to the + terminal block then power
and ground for the Receptor will be derived
automatically from the 4.8VDC power input for the
Hitchiker "J" style connector; the 9th one labeled "Bat".
This is less desirable due to increased current drain.
Power may be supplied to both the terminal block + and
"J" style. The "J" style +4.8 will run the servos and the
terminal block + will power the internal circuitry.
KH716 or KH732 OPERATION: Extend
transmitter antenna fully. Interference from regular
servo data sent by other PCM1024, AM or FM
transmitters on your frequency, although guarded
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against, can occur to the Hitchiker channels or
regular servo channels. This can be avoided by
proper frequency control protocol and turning on
your transmitter first, then your model. Reverse
procedure for powering down. For secure channels
and a truly unique transmitter identification code
ask about our industrial strength Kommander
Keykoder systems.
When purchased as a complete system the
KeyKoder comes installed and includes a minor
internal modification to the FP7CAP transmitter
and sometimes the receiver. If your components
require modification VANTEC will do it or supply
instructions to a qualified technician in your area.
We do not recommend customers modify the
equipment.
KH712 system: The Airplane KH712 system is
configured differently from the 16 and 32 channel boat
and robot systems. Although the transmitter still uses the
KH16T Keypad only 12 switches are effective.
Switches 1 through 8 on the KH16T KeyPad generate
only Servo Command Pulses and switches 13, 14, 15,
and 16 are the electronic switch outputs on the Receptor.
The KH12R companion Receptor doesn’t use an 18 pin
plug in terminal block. Instead it uses a pin-post
connector 2 X 5 array, sometimes called a .1" header,
labeled as Power/Switch Pairs. Mating connector pairs
with pigtail wires are included. The outputs 14, 16, 15
and 13 are the right 4 pairs. Each pair consists
of an electronic switch output and it's
corresponding ground. Be sure to connect each
output ground wire to the negative of the
battery used to power that channels device.
Usually in aircraft applications the same battery
is used for all devices.
The left-most pair of the Power/Switch Pairs is
the preferred power input connection for the
KH12R. The ideal power supply for the
KH12R is +12VDC connected to this pair's +D
pin-post, with the negative connected to the
pairs ground pin. The voltage input here may
range from 4.8-30VDC. When or if power is
not supplied to +D pin post then power and
ground for the Receptor will be derived
automatically from the 4.8VDC power input for
the Hitchiker servos "J" style "Bat" connector.
The Hitchiker is comes with a limited one year
warranty based upon a fixed repair charge for
units not tampered with, imersed or electrically
or mechanically abused. Call before returning
unit for repair. These products are not safety
devices nor for use in life-critical or life-
support systems. Specifications and prices
subject to change without notice. Patents and
patent pending may apply. Some trade names
and trademarks owned by others.
THE PCM ADVANTAGE
Early R/C transmitted each channels servo position as an analog pulse width that
ranged from 1-2 milliseconds. The pulses were transmitted as a continuous Radio
Frequency energy carrier with their beginning and end marked by Amplitude
Modulating the RF carrier "off" for 0.35 ms. The channels were sent sequentially with
the .35ms end mark of one serving as the beginning mark of the next channel. A
special long pulse delineated the beginning of the channel series, called a Frame. The
receiver used the marks to determine the channels, otherwise the receiver was dumb.
Any noise or interference in the "air" was interpreted as a marker pulse and mis-
commanded the servos because the receiver couldn't tell the difference. FM versions
suffer the same problems.
The Pulse Code Modulation receiver is smart; it contains a microprocessor. By clever
structuring of the servo commands using mathematics and precise timing PCM
facilitates accurate reception even with severe noise or interference.
It begins in the transmitter by conversion of each joystick position into a 10 bit digital
word plus bits to enable the receiver to mathematically verify the word. The next trick
of PCM is to compact this data representing 1024 servo positions/channel into the FCC
specified radio bandwidth while maintaining responsive "real time" control to fly a
helicopter. The PCM data is transmitted synchronously; each bit has a particular
position in time, within the Frame. The Frame continuously repeats. A precision
crystal controlled clock in the receiver locks onto the transmission to maintain
synchronization with the data bit by bit even during major signal drop outs. Thus the
receiver can process data immediately after interference instead of waiting for a
Framing pulse.
Received data is evaluated channel by channel. When the mathematics indicates an
error, previously validated channel data stored in the smart microprocessor is
substituted. If an error persists then failsafe servo operations previously specified by
the operator are initiated until accurate commands are again received. The
microprocessor converts the proper data into pulse widths to command the servos. No
more servo jitters!
Futaba's scheme gives 8 channels of 10 bit resolution. Other competitive systems limit
the resolution of some channels to 8 bits; 1/4 as accurate.
KeyKoder Devices & Tech
nology
The first add-on channel KeyKoder product was sold by
VANTEC in 1981. We have improved the product several
times since. In this fresh new design we deciphered Futaba's
PCM1024 format to capitalize on it's reliability for secure
robot applications. The on-off added-channel KeyKoder
described in this paper is fundamentally a 32 channel
KeyKoder device. In this new technology up to four
KeyKoder type devices can be piggybacked on one
PCM1024 servo channel. Four of these devices therefore
yields 128 on-off functions through a single servo channel.
Other KeyKoder device functions are available, for example
the transmitter ID and high security function, Key-on/Key-
off operation, or additional 8 bit resolution servo channels.
Some of these functions are available in our KIK29 and
KIK44 product. A slow speed data channel is also practical;
great for radio controlled advertising blimps or "calling"
special robot functions implemented by an on board
computer.
VANTEC is interested in your special control application
using KeyKoder technology; give us a call at (541) 471-
7135.
vantec.com Phone: [phone] FAX: [phone] Honeycutt Dr., Grants Pass, OR 97526 0410