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Below is a list of the parts included in the Quick-Connect Kit for the Multi-Trigger.
Click here for the Parts Guide for the PCB for Multi-Trigger Kit (MT-PCB2).
Click here for replacement or additional connectors. Click here for replacement or additional cable.
We may occasionally make changes to the parts list without notice in order to improve the product.
3.5mm mono (male)
These connectors are used for the microphone cord and the external trigger input.
For the microphone, the sleeve is connected to ground and the tip to the microphone input.
For an external trigger, the sleeve is connected to ground and the tip to the positive output line of the trigger.
3.5mm mono (female)
These are the female counterparts to the connectors above. Use them on jumper cables coming from the microphone and external trigger inputs on the PCB.
3.5mm stereo (male)
These connectors are used for the two photogate cords. One is for the interrupter-style photogate and the other for the individual emitter and detector style.
The tip is connected to +9 V, the ring to the photogate input, and the sleeve to a 470-ohm dropping resistor that then goes to ground on the PCB.
3.5mm stereo (female)
This is the female counterpart to the connectors above. Use this on a jumper cable coming from PT and LED2 on the PCB.
This is used as a connector on the cable from a flash unit or camera to plug into any of the four RCA panel jacks or female RCA connectors.
The sleeve is connected to ground and the tip to the desired output.
This is the female counterpart to the connector above. Connect to a jumper cable from D3 on the PCB.
Red and black 22-ga, single strand wire
2 ft each color
This hookup wire is used for the 4 jumper cables from the PCB. The wire will be cut into 6-in sections.
Green 22-ga, single strand wire
This wire is needed for the jumper for the photogate cable.
This cable is used to extend the microphone from the PCB.
3/32-in dia heat-shrink tubing
The heat-shrink tubing is used to insulate the splices on the microphone cable.
Quick-connect cables make it easy to connect and disconnect cables from the PCB. Each quick-connect cable involves preparing a female jumper cable that will be soldered to the PCB and soldering a corresponding male connector to the external cable that will connect to the jumper. We'll start with the jumper cables. Refer to Parts Guide above as needed to identify the connectors.
First cut each of the 2-ft sections of red and black single-strand wire into 4 equal 6-in sections. Then strip the end of each section a distance of about 1/8 inch. Also strip both ends of the green wire 1/8 inch. So you'll end up with 9 sections of wire stripped on the ends. Now remove the jacket from the female RCA connector as shown in Figure 1.
Loop one of the red wires through the shorter lug of the RCA connector as shown in Figure 2. Solder the connection.
Loop one of the black wires through the longer lug of the RCA connector and solder the connection. Clip off any lengths of wire extending between the solder joints. Figure 3 shows a completed solder job.
Now crimp the metal tabs over the wires as shown in Figure 4. Feed the jacket over the wires and screw onto the connector to complete the jumper cable.
Figure 1. Female RCA connector
Figure 2. Connecting the positive wire
Figure 3. Red and black wires soldered to connector
Figure 4. Connector with metal tabs crimped over wires
Figure 5. 3.5mm mono female connector soldered
Figure 6. Connections to 3.5mm stereo female connector
Figure 7. Connections of 3.5mm mono cables to PCB
Figure 8. Connections of RCA and 3.5mm stereo cables to PCB
Follow a similar process with the 3.5mm mono female connector. Use a different pair of red and black wires. (You'll use a different pair for each jumper cable.) Be sure to use the connector that has two lugs rather than three. We won't show all the steps this time; the completed connector is shown in Figure 5 before the jacket is screwed on. Note that the red wire is soldered to the shorter leg, similar to the RCA connector.
Prepare a second 3.5mm mono female jumper cable. You'll need two of them.
Next prepare the 3.5mm stereo female jumper wire. Hold the connector as in Figure 6 so that the long, central lug is farthest from you. The red wire will then connect to the short lug on the left, and the green wire will connect to the short lug on the right. The black wire connects to the long, central lug. See the photo to the right for another view. Go ahead and solder the wires and complete the connector.
That completes the jumper cables. Now you'll solder them to the PCB. The 3.5mm mono cables are soldered to the locations shown in Figure 7. See Figure 8 for the other two cables. The RCA cable is soldered into the A and C holes on either side of the D3 SCR. The 3.5mm stereo cable is soldered into the PT + (red), PT - (green), and LED2 - (black) holes. (The LED2 + hole isn't used, because it's connected to PT + on the PCB.)
Below is a view of the completed PCB with all jumper cables. Note the stick-on labels that have been added to the switches.
The next thing to do is prepare the cables that will connect to the jumpers.
Here's what you'll need for the microphone cable: the 3-ft length of 2-conductor cable, the 3.5mm mono connector (male), the heat-shrink tubing, and the piezoelectric disc from your Multi-Trigger. Cut the 3/32" heat-shrink tubing into two 1-inch lengths and slip them onto the red and black wires of the piezo disc. Then strip the ends of the wires about 3/4".
From one end of the gray 2-conductor cable, strip the gray insulation back 3/4". Then strip each of the red and black wires 3/4".
Twist the red wire of the piezo disc around the black wire of the 2-conductor cable. Likewise, twist the black wire of the disc around the red wire of the cable.
Solder the connections.
Slip the heat-shrink tubing over the soldered wires and run a lighter or match flame under the tubing to shrink it but not so close as to burn the tubing.
Slip the 3" section of 3/16" heat-shrink tubing onto the cable and over the spliced connections. Heat shrink it into place.
Remove the jacket from the 3.5mm connector and slip it over the cut end of the cable. The threaded end must be toward the cut end of the cable. Strip back the gray insulation on the free end of the cable about 1/4" and then strip the insulation on the red and black wires about 1/8".
Insert the stripped wires into the holes on the terminals of the 3.5mm mono connector. The red wire goes in the shorter terminal. Don't crimp the metal tabs around the cable yet, as this will cause the insulation to melt when you solder.
Solder the connections. Since there's so much metal, it will take some time for the soldering iron to heat the metal. Hold the tip of the iron flat on the metal to heat it up in the vicinity of where you want to solder. Touch the solder to metal and wait for it to start flowing. This is the way to ensure a good electrical connection rather than a cold solder joint.
Clip off any stray wires and then crimp the metal tabs around the gray cable.
Screw on the jacket, and your microphone cable is complete.
External Trigger Cable
The microphone cable will connect to the corresponding 3.5mm mono jumper cable on the PCB. The other 3.5mm mono jumper is for an external trigger input. This allows the delay unit of the PCB to be used with any HiViz.com trigger circuit or, in fact, any circuit that provides a short circuit output. The external trigger input can also be used with a simple contact trigger such as the one shown here. If you will be using an external trigger with the PCB, you'll need to provide a 2-conductor cable. If you'll be using a HiViz.com trigger circuit as the external trigger, just use the output cable that came with that circuit. Connect to one end of the cable a 3.5mm mono connector (male) like you did for the microphone cable above. Connect the red wire to the shorter terminal of the connector and the black wire to longer terminal. The other end of the cable will connect to the output of your external trigger circuit.
Now let's move on to the photogate cables. Your Multi-Trigger has two types of photogate cables, the interrupter style and the separate emitter and detector. We're assuming that you've already made up those cables so that you can continue below.
Select one of the two photogate cables to start with. You'll add a 3.5mm stereo male connector to the cut end of the cable. The wires are probably already stripped for connection to a breadboard. If so, cut off the stripped wires. Then, before stripping them again, unscrew the jacket of the connector and push it onto the cable. Now, strip the gray insulation back about 1/4" and the individual wires about 1/8".
The terminals of the connector are numbered in the photo to the left. The black wire will connect to 1, the green wire to 2, and the red wire to 3. If you have trouble getting all the strands through a hole, you can clip off the strands that won't fit.
Here we show two views of the assembly with connections soldered and stray strands clipped.
Crimp the metal tabs around the cable and screw on the jacket to complete the assembly.
A second 3.5mm stereo connector is supplied with your quick-connect kit to attach to the other photogate cable. The completed cables are shown to the left.
In order to connect your Multi-Trigger to a flash unit or camera, you need a trigger cable such as one of the four shown in Figures 36 - 39. These 2-conductor cables have a connector for the flash or Opto-Switch on one end and bare wires on the other end. The 2-conductor cable is supplied with your Multi-Trigger kit, but the connector is not supplied. For the following, you'll first need to prepare such a cable if you haven't already. Then proceed below.
In order to connect the cable to the RCA jacks on the PCB, you'll need to solder a male RCA connector to the bare wires on the cable. Continue below the photos to prepare the cable.
Figure 36. PC cable to connect flash to breadboard
Figure 37. Adapter to connect flash foot to breadboard
Figure 38. Cable to connect Camera Opto-Switch to breadboard
Figure 39. Cable to connect a Vivitar 283/285 flash to breadboard
Unscrew the black jacket from the RCA plug as shown to the right.
For whichever of the four cables shown in Figures 36-39 that you're preparing, cut off the free red and black wires where they extend from the gray insulation. Then push the black jacket over the cable as shown in Figure 40. If you find the fit too tight, snip off part of the collar that grips the cable. Once you have the jacket on the cable, strip back the gray insulation 1/4 inch. Then strip the red and black wires 1/8 inch as shown in Figure 40.
Important: Don't crimp
the metal tabs around the gray insulation before
soldering. If you do, the heat of soldering can
melt the insulation. Now thread the red wire through the
smaller of the two solder lugs and solder it.
Then solder the black wire to the longer lug.
This lug can take a lot of heating since there's
so much metal. Make sure that it gets hot enough
for the solder to flow freely. The metal takes
a while to cool down, so don't touch it for a
while. After you've finished soldering,
examine the connections for stray wire strands.
Clip off any that you find. Figure 41 shows
the completed solder joints. If you have a connectivity meter,
use it to check for correct connectivity. The
tip of the plug is electrically connected to the
shorter lug, and the collar is electrically connected
to the longer lug.
Crimp the metal tabs around the
gray cable and screw the jacket on. The completed
connector is shown in Figure 42.
A completed cable for connection from the PCB to a flash unit is shown in Figure 43. This completes assembly of the PCB, and it is now ready for testing.
Figure 40. Stripping wires in preparation to add RCA connector
Figure 41. RCA plug connected to the red and black wires
Figure 42. RCA plug connected to cable
Figure 43. PC cable ready to connect to PCB
An Extra Trigger Cable
Up to this point, there's one connector you haven't used; it's a male RCA connector. With this spare RCA connector, you can make a second trigger cable so that you'll have one for your flash and another for your camera.
Operating the PCB Multi-Trigger (with quick-connect cables)
Figure 44. Photogate with delayed flash
Figure 45. Photogate with delayed camera
Figure 46. Dual camera and flash triggering
Figure 47. Instant and delayed flash
Photogate with delayed flash (Figure 44)
Lay the PCB out on a non-conducting, static-free (as much as possible) surface. The lid of a plastic project box will work or just a piece of cardboard or the pink antistatic bag that many of our kits are shipped in. The thing to avoid is any surface that will discharge to the PCB or that will create shorts between the metallic contacts on the back of the board. Now do the following:
Connect a photogate cable. For testing, we recommend using the cable with individual emitter and detector. That way, you can test the effect of changing separation. However, either photogate cable can be used. If you're using the individual emitter and detector, tape them down a few inches apart facing each other.
Set the input selector switch to PG.
Set the delay range to 0.5 s.
Turn the timeout knob about a quarter of the way clockwise from its minimum position.
Turn the coarse delay (blue knob) all the way clockwise. The position of the fine delay (brown knob beside the blue knob) doesn't matter at this stage.
Connect your flash to the delayed flash (FLA Del) output of the PCB using your trigger cable. Turn on your flash, preferably to low power.
Connect a fresh 9-V battery to the battery clip.
The photogate alignment LED should be lit. If it isn't, try adjusting the white sensitivity pot one direction or the other. Setting the pot near the middle of its range should work. Note that if you change the separation of the infrared LED and PT, you may need to adjust the sensitivity to compensate. Try this if you want to see how you have to turn the pot to get the alignment LED to stay on.
Run a finger between the infrared LED and PT. The alignment LED should go out momentarily. At the end of a short delay of about 1 second, the triggering indicator LED should light momentarily, and your flash should also discharge.
Try the following adjustments to see how they affect the triggering indicator and the flash when you run your finger through the infrared beam.
Turn the coarse delay down about half way. You should notice a reduction in the delay.
Make a large change in the fine delay knob position. You probably won't notice a change in the delay. There actually is a change, but it would only be noticeable when photographing a high-speed event.
Now turn the coarse delay up all the way and flip the delay range to 0.05s. This time you won't notice a delay. The switch divides all delay intervals by 10. You would use this setting when you need particularly small delays. For now, flip it back to the 0.5s position.
Turn the timeout all the way up. This doesn't affect the delay, but it does increase the amount of time that the triggering LED is on. At maximum setting, this is about 1 second. This setting can be used to prevent multiple-exposures that would result from the flash unit going off more than once in quick succession.
Notes on operation:
If you turn the timeout all the way to zero, the triggering indicator LED won't light but the delay unit will still provide an output.
If you turn both coarse and fine delays all the way to zero, the unit won't trigger. Turn the fine delay up just enough to get triggering.
Unclip the battery when you're not using the circuit. Otherwise, the photogate will drain the battery overnight.
Photogate with delayed camera (Figure 45)
This setup is for triggering a camera shutter through an Opto-Switch. The difference between Figures 44 and 45 is the output connection. The trigger cable is connected from the delayed camera (CAM Del) output to the TRIG jack on the Camera Opto-Switch. The camera shutter cable is connected from the CAM jack of the Opto-Switch to the camera. Both FOCUS and SHUTTER switches are on. Running your finger through the photogate should actuate your camera shutter after whatever delay you've selected.
Specialized setup: Dual camera and flash triggering (Figure 46)
This arrangement is useful for photographing drops and splashes. The interrupter photogate is used. Connect the trigger cable from the Opto-Switch to the instant camera (CAM Inst) output in order to actuate the camera with no delay other than the inherent lag associated with the camera shutter. Connect the flash to FLA Del. The shutter speed is set to, say, 2. The photogate would be set up, say, a foot or less above the pool and the delay adjusted to capture the collision of the drop with the pool. When the drop passes through the photogate, the camera shutter opens and remains open for half a second. This is long enough for the drop to reach the pool and the flash to discharge. The shutter then closes automatically.
Specialized setup: Instant and delayed flash (Figure 47)
If you connect one flash to FLA Del and another flash to the RCA jumper cable from the instant output of the delay unit, then you can discharge two flashes units a short time interval apart for high-speed double exposures. While Figure 47 shows an interrupter photogate cable connected, the sound trigger or an external trigger could be used instead. Information about using external triggers is provided later.
Figure 48. Sound trigger with flash on ST OUT
Figure 49. Triggering a flash with the Opto-Switch
Figure 50. Contact trigger as external input
Figure 51. Triggering a flash with wireless devices
Sound trigger with flash on ST Out (Figure 48)
Set the following:
Set the input selector switch to PG.
Turn the red sensitivity knob all the way counterclockwise. This is the least sensitive position.
Connect your flash to ST Out of the PCB.
Clap your hands or snap your fingers. The flash should discharge. This setup provides a nearly instantaneous discharge of the flash unit. The only significant delay is the time for sound to take to travel from the source of the sound to the piezoelectric disc. This setup is recommended for photographing balloon bursts, which happen very quickly. If you need to change the delay, you do so by moving the microphone different distances from the source of the sound. You can figure that there's a delay of about a millisecond (thousandth of a second) per foot (third of a meter) of distance.
Now turn up the sensitivity until the flash discharges spontaneously. This typically happens after the half-way position. When you reach the position where the flash discharges spontaneously without sound, this means the circuit is so sensitive that it's always on. In this condition, the flash will no longer discharge. If you turn the knob just enough counterclockwise so that the flash will discharge with a snap of your fingers, then you're at the point of maximum sensitivity. We recommend that you not operate at this point if you don't need to. Keeping the knob turned about one-quarter of the way is a good operating position.
Note on operation: With the input selector on PG, you're bypassing the delay unit, which has no function when using ST Out. With the delay unit bypassed, the triggering indicator LED doesn't flash. While you could also have put the input selector on MIC, this isn't recommended if your flash unit has high voltage across its terminals. The latter can burn out the 556 timer when the flash is connected to ST Out and the input selector is set to MIC.
Sound trigger with delayed flash (no figure)
If you move the trigger cable to the FLA Del output and flip the input selector to MIC, then you can use the sound trigger with the delay unit. The delay unit functions the same as for the photogate described previously. Note, though, that the sensitivity will drift from the setting for ST OUT. If, say, you have the sensitivity set to its maximum as described above, then you'll find that the delay unit won't function with the sound trigger. But if you turn the sensitivity down, you can get the delay unit to function. That's why we recommend keeping the sensitivity at the one-quarter position. You won't have to worry about the drift in sensitivity when switching to the delay unit.
Specialized setup: Triggering a flash with the Opto-Switch (Figure 49)
You can trigger a flash unit with the Opto-Switch as long as the flash unit doesn't have high-voltage terminals. In this case, high voltage means greater than 75 V. The trigger cable is connected from either of the CAM outputs on the PCB to the TRIG jack on the Opto-Switch. The CAM jack on the Opto-Switch is connected to the flash unit. An adapter may be required to convert RCA male on the flash trigger cable to 3.5mm male on the Opto-Switch. The adapter shown in the photo on the right will work. In operation, the SHUTTER switch is turned on; the FOCUS switch may be on or off. While the photo shows the photogate connected, the sound trigger or an external trigger could also be used. (See below about connecting an external trigger.)
One possible application is to double your flash output. Connect one flash to the CAM Del output using the Opto-Switch and another flash to the FLA Del output. The two units should discharge essentially simultaneously.
Using the External input (Figure 50)
You can connect other triggers to the delay unit using the external input. The output of the trigger must be a simple circuit closure in order for this to work. A contact trigger such as the one shown in the photo is a useful external trigger. Connect to the PCB using the external input jumper cable. When using an external input, the input selector must be set to MIC.
Specialized setup: Triggering a flash with wireless devices (Figure 51)
You can connect a wireless transmitter to either ST Out or DEL Fla and trigger a flash unit connected to a wireless receiver. Note that an adapter may be required to connect the trigger cable from the delayed output to the transmitter. The type of adapter will depend on the jack on the transmitter. For the PocketWizard Plus II unit shown, an adapter like the one shown previously will work. Be aware that the use of a wireless transceivers introduces an additional delay of 1-2 milliseconds, whether using an instant or delayed output.
Connecting a Direct photogate output
There isn't a direct output jack from the photogate, because this is rarely used. If, however, you wish to have a direct output, connect a jumper cable to the holes labeled A and C in Figure 52 below. Solder the positive wire of the trigger cable to A and the negative wire to C. Note that this output is for flash rather than camera.