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Assembly and Operating Instructions for Kits


Assembly Instructions for the SK3 Sound Trigger


Assembly instructions for other kits




What you need

Parts guide (opens in new tab or window)

A helpful reference (includes circuit schematic)

Soldering the fixed-value resistors to the PCB

Soldering the IC socket to the PCB

Soldering the capacitors to the PCB

Soldering the SCR to the PCB

Preparing the microphone cable

External input cable (optional)

Preparing the trigger cable

Drilling holes in the project box lid

Adding the components to the project box lid

Wiring the box lid

Completing the assembly

Testing and operating the sound trigger


About the images: Clicking on any image will open a larger version on top of the page. If you prefer to have the larger images open in a different tab or window, right click on the image and make the appropriate selection.


What you need


PCB for Sound TriggerThese instructions show how to prepare and use the PC board and project box enclosure for the SK3 Sound Trigger. The kit comes complete with all the parts needed for assembly of a working sound trigger on a PC board enclosed in a project box. Also included are the parts to prepare the microphone and cable.


The PC board is shown to the right. Click on it for a larger view. You'll see that the locations for the components are labeled with symbols like R1, C1, etc. This makes it easy to find where to place the components. You'll need to solder the components to the back (non-printed side) of the PCB. We'll provide guidelines for getting good solder joints, but we recommend that you have previous experience soldering on a PC board. With soldering, you can't make changes easily like you can with a breadboard. If you solder something in the wrong place, repair can be time-consuming.


Having the right tools will make the job easier. You'll need to provide your own. Here's what we recommend.


For soldering

  1. 15-30 W soldering iron (with a new or pointed tip) and solder
  2. Wire stripper (photo below)

  3. A small diagonal cutter (photo below) makes it easy to trim the legs of the components after you solder them to the PCB, but other kinds of snipping tools such as scissors may work.

  4. Needle-nose pliers (photo below) make it easier to handle small components, especially if you have big fingers.

  5. A heat sink (photos below) protects heat-sensitive components while soldering.

  6. A desoldering tool (photos below) helps in clearing solder from a hole. The cylindrical type works better than the bulb.

  7. A magnifying glass is used to inspect solder joints.

  8. A lighter or matches to shrink heat-shrink tubing

    Wire cutters and stripper

    Small diagonal cutter

    diagonal cutter

    Needle-nose pliers

    needle-nose pliers

    Heat sinks

    heat sink clip heat sink clip

    Desoldering tools

    desoldering tool desoldering bulb


Be sure to solder in a well-ventilated area. Keep the tip of your soldering iron clean by wiping it against a wet sponge. Once the tip is clean, touch a bit of solder to the tip to tin it and improve heat conductivity. Inspect your solder joints to see if the solder flowed well to make good electrical contact. If it looks like the solder formed a bead, that's likely a bad joint and will not conduct. Reheat to flow the solder.


For the project box

  1. Drill motor and bits to drill holes in the project box lid. Bit sizes are 3/32", 1/8", 1/4", and 5/16". (For metric equivalents in millimeters, multiply by 25.4.) You can substitute a 1/8" bit for the 3/32" one.
  2. Hammer, punch (or nail), small round file
  3. Wrenches or sockets to tighten components onto the project box

Parts guide


Click here for a detailed, illustrated list of all the parts you'll need. You can use this list to identify the parts and make sure you have them all.


A helpful reference


It will be helpful to print this pdf document for reference while you work. There are lists of component placements and jumper wire connections. For those who like to use circuit schematics, there's a complete schematic of the circuit.


Soldering the fixed-value resistors to the PCB


100k-ohm resistorIf you don't have your soldering iron heated up, do that now, because you'll be soldering before long. You'll be doing some detailed soldering work, so an iron with a good tip will make it easier. Let's start with R1, a 1-kohm resistor. See the photo to the right, and refer to the Parts Guide as needed for parts to come. The resistors are identified by the sequence of 3 colored bands, read from left-to-right. (The 4th, gold band indicates that the actual value of the resistance is plus or minus 5% of the value given by the color code.) For the resistor shown to the right, the bands are brown-black-red.

  1. Insert the legs of resistor R1 over the rectangular space labeled R1 on the PCB. See Figure 1. (Click on it for a closeup view.) You can flip the resistor either way in the holes; the orientation doesn't matter for resistors, since resistors work the same no matter which way current flows in them.

  2. Push the resistor in until it's flush with the surface of the PCB. Then flip the PCB over. Figure 2 shows the legs protruding from the back of the board.

  3. Next you'll solder. Tin the tip of the soldering iron by melting some solder on it. Then bring the point and the solder down to one of the holes where the resistor protrudes as in Figure 3. Melt some solder around the base; it doesn't take much. The solder should flow down into the hole around the leg of the resistor to make a good electrical joint. Now solder the other leg.

  4. Turn the board over to verify that solder filled the holes. See Figure 4. If you don't see that solder melted through to the upper side, it's probably a good idea to melt some more solder into the hole from the back of the board. You can melt solder onto the front of the board if you prefer.

  5. When your solder joints are complete, snip off the legs of the resistor down to the solder joint.

inserting R1 R1 from back of PCB Soldering a leg of the resistor R1 from back of PCB
Figure 1. Resistor R1 inserted into dedicated space on PCB Figure 2. Legs of resistor R1 protruding from back of PCB Figure 3. Soldering a leg of the resistor Figure 4. Inspecting the finished solder joints
  1. Solder the 10-ohm resistor (brown-black-black) into R2 on the PCB.
  2. A 1-kohm resistor is supplied for R3; however, you should only use this if you want the sound trigger to have particularly low sensitivity. Otherwise, we recommend that you simply solder a jumper wire in place of R3. Cut a 1-inch section of hookup wire, strip the ends, and bend them over as shown in Figure 5. Then solder the wire to the board.
  3. The board with the two resistors and the jumper wire soldered into place is shown in Figure 6.
Jumper wire to replace R3 board with all resistors
Figure 5. Jumper wire to replace R3 Figure 6. PC board with fixed-value resistors mounted


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Soldering the IC socket to the PCB


The 8-pin IC socket will be used to seat the LM386 IC. The latter won't be added to the socket until later, since the IC can potentially be damaged by heat.

  1. See Figure 7. Note that the socket has a notch on one end. You'll line this notch up with the one on the PCB when you seat the socket into the board.

  2. Place the 8 pins of the socket into the corresponding holes on the PCB as shown in Figure 8.

  3. Turn the board over and bend the pins down to the side to hold the socket in place as shown in Figure 9.

  4. Solder the 8 pins to the board. The finished result is shown in Figure 10. Check with a magnifying glass to make sure there are no solder bridges or hairs between pins. If so, remove them by running the tip of the soldering iron between the pin.

8-pin socket notch seating the 8-pin socket Crimping the 8-pin socket 8-pin socket soldered to PCB
Figure 7. Notches on the socket and the PCB Figure 8. 8-pin socket seated on PCB Figure 9. Crimping the pins of the 8-pin socket Figure 10. 8-pin socket soldered to PCB


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Soldering the capacitors to the PCB


Via holeSomething to be aware of before you do more soldering is that there is one hole on the board that is a via hole rather than a solder hole. See the circled hole above C3 in the photo to the left. The solder holes are for the component legs. The via hole, which is smaller than the solder holes, is a place where there are connections between the upper and lower conducting layers of the board. Don't try to solder a component leg into the via hole. If, however, you get solder in a via hole, that's not a problem.


There are two kinds of capacitors, ceramic and electrolytic. Two of them are ceramic capacitors.They all have a disc shape, are orange or tan in color, and are non-polar. The latter means that it doesn't matter whether the legs are switched when inserted into the holes on the PCB. A number on the disc identifies the capacitor. The capacitor in Figure 11, for example, has the number 473. From the Parts Guide, you can determine that this is a 0.047-μf capacitor. There are 4 electrolytic capacitors. These have cylindrical, blue cases, and they are polar. So you have to be careful of the orientation in which they're inserted into the PCB. The negative leg of an electrolytic capacitor is the shorter one. The value of the capacitance is written on the side. Figure 12, for example, shows a 10-μf capacitor.

  1. Figure 13 shows the 2.2-μf capacitor beside the location C1 on the PCB where the capacitor will be soldered. The "+" sign printed on the board indicates where the longer, positive leg is inserted. Insert the legs of the capacitor into the holes but leave about 1/8" of the legs protruding as shown in Figure 14. Bend the legs over on the back. Then solder the legs on the back and snip them. The completed solder job is shown in Figure 15.

  2. Figure 16 shows the 0.1-μf capacitor (104Z) resting on the PCB above the location C3 where the capacitor is to be mounted. Insert the legs of the capacitor into the C3 holes, again leaving about 1/8" of the legs protruding. Bend the legs over on the back, solder, and snip. The completed solder job is shown in Figure 17.

  3. Solder the remaining capacitors onto the board in the locations as indicated below:

    C2: 10 μf (electrolytic)

    C4: 100 μf (electrolytic)

    C5: 470 μf (electrolytic)

    C6: 0.047 μf (473; ceramic)

Figure 18 shows all capacitors mounted on the PCB.

0.0047-uf capacitor 10-uf capacitor 2.2-uf capacitor with PCB C1 capacitor inserted into PCB
Figure 11. 0.047-μf ceramic capacitor Figure 12. 10-μf electrolytic capacitor Figure 13. 2.2-μf capacitor beside the location C1 where it is to be mounted Figure 14. Capacitor C1 inserted into PCB
soldering of 2.2-uf capacitor completed 0.1-uf capacitor on PCB 0.1-μf capacitor soldered into location C3 PCB with all capacitors soldered in place
Figure 15. C1 capacitor soldered to the board Figure 16. 0.1-μf capacitor on the PCB above location C3 Figure 17. 0.1-μf capacitor soldered into location C3 Figure 18. PCB with all capacitors soldered in place


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Soldering the SCR to the PCB

  1. Slip the SCR (labeled TYN408G) into the three holes for the SCR on the PCB. Note the orientation of the SCR in Figure 19.

  2. The SCR is heat sensitive. While it has a metal backing that serves as a heat sink, it is nevertheless a good idea when soldering to clip a heat sink on the legs as shown in Figure 20. Go ahead and solder the legs and snip them.

  3. The PCB with all components soldered is shown in Figure 21. Note that the POT and LED will be mounted on the lid of the project box rather than on the PCB. Also jumper wires will be added later to connect to the PCB to the lid.

SCR positioned on the PCB Using a heat sink on the SCR legs PCB with all components soldered
Figure 19. SCR positioned on the PCB Figure 20. Using a heat sink on the SCR legs Figure 21. PCB with all components soldered  


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Preparing the microphone cable


Here's what you'll need for the microphone cable:

  • 3-ft length of 2-conductor cable
  • 3.5mm mono connector (male)
  • 2 inches of 3/32-in heat-shrink tubing
  • 3 inches of 3/16-in heat-shrink tubing
  • piezoelectric disc

Begin by cutting 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. The cable will connect to the corresponding 3.5mm mono jack on the enclosure once that part of the project is complete.


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Preparing a trigger cable


The trigger cable isn't provided with the SK3 kit, because there are different methods of connecting to a flash unit. You may have purchased one of our trigger cable kits to use with the SK3. If so, follow the online instructions for your kit to prepare the cable. Three versions of completed trigger cables are shown in Figures 22 to 24 below.

PC cable ready to connect to PCB Hot shoe adapter ready to connect to PCB Trigger cable for Vivitar 283

Figure 22. PC plug to RCA plug

Figure 23. Hot shoe adapter to RCA plug

Figure 24. Vivitar 283-type plug to RCA plug


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Drilling holes in the project box lid


Note that due to some editing in the instructions, the figure numbers jump from 24 to 30.

  1. The template is sized to fit snugly within the underside of the project box lid (that is, on the interior side of the box). Position the template inside the lid as shown in Figure 30. Then use a nail or punch to mark the positions of the centers of the holes to be drilled.

  2. Remove the template and drill the holes. We recommend drilling small pilot holes first, for example, 3/32" or 1/8". The plastic has a tendency to grab the bit, so hold the plastic securely. We've found that spade bits work best for drilling the 1/4" and 5/16" holes.

  3. Use a round file to clean up any burrs around the holes. The lid with holes drilled is shown from underneath (Figure 31) and from above (Figure 32).
template in underside of project box lid Project box lid from underside after holes drilled Top of project box lid after holes drilled  
Figure 30. Template placed in underside of project box lid Figure 31. Underside of project box lid after holes drilled Figure 32. Top of project box lid after holes drilled  


Adding the components to the project box lid

  1. LED holderWe recommend adding the LED first, since people tend to have difficulty getting the holder to snap into place. The LED mount has two parts, which we will call the collar and the ring. (See photo to the right.) The collar is first slipped into the hole on the project box from the top side toward the interior of the box and snapped into place. Then the LED is pushed up into the collar from below and snapped into place. (Note the orientation of the legs of the LED in Figure 33.) It's important that you push the LED all the way up until it snaps into the collar. It may take quite a bit of extra force to push it the last bit of the way. You'll know it's in when it snaps. If you don't push the LED in all the way, it will be loose in the collar. See Figure 33 showing the LED after being snapped into place. Note how the bottom of the red case sits down inside the collar. Also see Figure 34 which shows the LED from the top of the box. Note how far it extends above the collar.

  2. Once you have the LED snapped in, push the ring over the collar from below. See Figure 35 for the completed assembly.

LED inserted into collar from below LED from above Completed LED holder assembly  from below
Figure 33. LED inserted into collar from below Figure 34. LED from top of project box Figure 35. Completed LED holder assembly from below  


For the remaining components, we don't provide step-by-step photos. Refer to the Parts Guide if you need to identify parts. The completed assembly of all components on the project box lid is shown in Figures 36 and 37 from below and above, respectively.

  1. Remove the nut from the 3.5mm jack, insert the jack through the box lid from below, and screw the nut back on. Needle-nose pliers can be helpful in tightening the small, round nuts. In Figure 36, note the orientation of the tab on the side. This orientation will aid in wiring later.

  2. Remove the nut from the AC/DC input jack, insert the jack through the box lid from below, and screw the nut back on. You can use a wrench on this nut.

  3. For each of the two RCA jacks, remove the nut and metal tab from the jack, insert the jack through the box lid from above, slip the metal tab and washer on under the box lid, and screw the nut on. While you can use a wrench to tighten these, keeping the jack from turning while tightening requires a strong grip on the jack. In Figure 36, note how the tabs circled by the yellow line are arranged so that the holes align. While this arrangement means that you can make the connection to both tabs with a single wire, it also makes soldering more difficult, because you have to heat up two tabs rather than one. You may find it easier when you get down to soldering to keep the tabs separated.

  4. The switch has a retaining ring with a key tab, a washer, and a nut. Remove all three and then insert the switch from below. Orient the slot on the threads to be on the same side as the 3/32" key hole. Then slip the retaining ring on so that the key tab slips into the 3/32" hole. Slip on the washer and nut and tighten.

  5. The potentiometer also has a key tab but this is on the body of the pot. Remove the washer and nut from the pot, slip it in from below and orient it so that the key tab passes up through the 1/4" key hole. Then put on the washer and nut and tighten.

Components mounted on project box lid (view of underside) Components mounted on project box lid (view of the top)  
Figure 36. Components mounted on project box lid (view of underside) Figure 37. Components mounted on project box lid (view of the top)    


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Wiring the box lid


Some of the components on the box lid will be hardwired to each other before making connections to the PCB. Here are some important tips about soldering in addition to those given previously.


Soldering to the legs of the LED: The LED can be damaged by excessive heat; therefore, it's a good idea to clip a heat sink to the leg when soldering.


Soldering the switch: Solder quickly, because the plastic can melt and break the internal contacts.


Soldering the 3.5mm jack: The lugs on the jack bend and break easily. Go easy on them.


Soldering the AC/DC jack: Be very careful not to get too much solder on the lugs so that the solder drips down, particularly on the center lug. If the solder drips down, it can create a dead short between the positive and negative power terminals. It may help to turn the box lid sideways when soldering.


Soldering the RCA jacks and pot: These components have a lot of metal and will take longer to heat up than the other components will. You're not likely to damage a pot but you could soften the plastic in an RCA jack.


About cold solder joints: If you don't heat the metal before soldering the wire, the solder may not bond with it and you can get an open circuit. You can't necessarily tell by looking that you have a cold solder joint. The best approach is prevention by using good soldering techniques. Hold the tip of the soldering iron flat against the metal surface that you're soldering to. Touch the solder to the metal nearby rather than to the soldering iron. When the metal is hot enough, the solder will flow. Flow enough solder on the connection to fill the hole and cover the connection, but don't leave the soldering iron on the metal any longer than it takes to flow the solder. Examine the connection under a magnifying glass. If the solder beaded up, you may not have a good connection.

  1. The red hookup wire will be used for +9V connections. Cut a 4-in length of the red wire and strip one end back 1/2 inch. Then wrap the wire around a small nail or similar object as shown in Figure 38. Pull out the nail and slip the wrapping down onto the longer leg of the LED as shown in Figure 39. Clip a heat sink to the leg before soldering.

  2. Strip the other end of the red wire back about 1/4 inch and connect it to lug 3 of the AC/DC jack shown in Figure 40. Figure 41 shows an enlargement of the jack with the lugs numbered the same as in Figure 40. Don't solder to the AC/DC jack yet, as you'll be connecting another wire to lug 3 later.

  3. The white wire will be used for ground connections. See Figure 42 for the connections that you need to make . If you arranged the RCA jacks with tabs separated, connect the tabs with a section of the white wire in addition to the other connections shown. Cut the wire to the appropriate lengths being sure to leave a 1-in length for later use. You can solder all connections now except the one circled in yellow. See the notes in the yellow box above about soldering the various components.

  4. Next you'll cut the jumper wires that will connect the parts on the lid to the PCB. Refer to the table below for the lengths that you'll need. In the next step, we'll tell you about the connections.

Color Length (in) Connection on lid Connection on PCB
White 1 Left lug of pot 1
Red 2.5 Lug 3 of AC/DC jack 3
Blue 3.5 Center lug of lower RCA jack (switch output) 4
Yellow 3.5 Center lug of upper RCA jack (pulse output) 6
Green 4.5 Microphone jack (+ pin) 7
Yellow 3.5 Center lug of pot 9
Green 3.5 Right lug of pot 10
Blue 3.5 Shorter leg of LED LED -
  1. Figure 43 shows the connections of the jumper wires to the components on the lid. The numbers beside the wires refer to the holes on the PCB to which the wires will connect. You can solder the jumper wires now.

  2. Use 4 of the 4-40 bolts to connect the 4 standoffs to the lid of the box as shown in Figure 44. Lay the four jumper wires shown (green, yellow, blue, white) to the left through the standoffs. These wires will pass under the PCB.

  3. One of the standoffs should be wrapped with electrician's tape to insulate it from possible contact with one of the wires that will connect to the PCB. See Figure 45. Continue with instructions below the photos.

Wire wrapping Preparing to solder the longer leg of the LED Red wire connected from LED to AC/DC jack AC/DC jack lugs (numbered)
Figure 38. Wire wrapping Figure 39. Preparing to solder the longer leg of the LED Figure 40. Red wire connected from LED to AC/DC jack Figure 41. AC/DC jack with lugs numbered
AC/DC jack lugs (numbered) Jumper wires connected to components Standoffs connected to box lid Standoff insulated with tape
Figure 42. Connections of the ground wires Figure 43. Jumper wires connected to components Figure 44. Standoffs connected to box lid Figure 45. Standoff insulated with tape
Jumper wires soldered to PCB Figure 47. PCB bolted down to the standoffs Adding the battery holder Seating the LM386
Figure 46. PCB oriented on lid Figure 47. PCB bolted down to the standoffs Figure 48. Adding the battery holder Figure 49. Seating the LM386
  1. Orient the PCB on the standoffs as shown in Figure 46.

  2. Bring the jumper wires up through the corresponding numbered holes (see table above) and solder them to the board from the top. See Figure 47. Bolt the PCB to the standoffs using the remaining 4-40 bolts. If you haven't already clipped off the legs of the LED above the solder joints, do that now.
  3. Solder the red wire of the battery holder to hole 2 on the PCB and the black wire of the battery holder to lug 1 of the AC/DC jack. See Figure 48.
  4. Orient the LM386 IC as shown in Figure 49. Note the location of the circular indentation in the upper left-hand corner of the IC. Make sure all eight legs are lined up with the corresponding holes and push down firmly to seat the IC.

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Completing the Assembly

  1. Remove the backing from one side of the hook-and-loop tape and stick it to the bottom of battery holder. Then remove the backing fromt the other side and slip the lid assembly into the project box as shown in Figure 51. Stick the battery holder down to the bottom of the project box interior on the opposite side as the PCB. Then close the lid being careful not to get wires caught under the lip of the lid. Don't screw down the box lid until after you've completed testing in the next section.

  2. Cut out the labels, remove the backing, and position the labels as shown in Figure 52. Tighten the knob onto the potentiometer shaft using the set screw.



Seating the battery holder and PCB in the project box Sound Trigger enclosure with labels



Figure 51. Seating the battery holder and PCB in the project box Figure 52. Sound Trigger enclosure with labels    


Testing and Operating the Sound Trigger


Sound Trigger with microphone cable and flash trigger cable connected
Figure 53. Sound trigger with microphone cable and flash trigger cable connected


LED on and flash tests

  1. Open the box and put a fresh 9-V battery in the battery holder. Then close up the box. Turn the SENS knob about 3/4 of the way clockwise. Insert the microphone cable into the MIC jack and your flash trigger cable into the S jack as shown in Figure 53. Connect your flash unit to the other end of the trigger cable and turn the flash on. By the way, the switch output (S) is protected with a 400-V SCR. Therefore, if your flash has a high voltage trigger circuit, it won't damage the sound trigger.
  2. Turn on the sound trigger. The LED should light.
  3. Snap your fingers. The flash should discharge. Walk away from the trigger across the room and snap your fingers. The flash should discharge.

If your trigger passed the tests, you're ready to use it. If not, turn it off, pull off the cover and touch the battery and the LM386. If either of them are hot, you have a short somewhere so you'll need to look for a place where two bare wires are touching that shouldn't be. Check the AC/DC adapter to see if solder dripped down from a lug into the base of the jack. If the battery and LM386 aren't hot, the next thing is to look for things like missing wires, incomplete solder joints, and capacitors with polarity reversed. In the first two units that the author assembled, there was a capacitor with reversed polarity in one unit and a missing ground wire in the other unit. So mistakes can be made even if you've had a lot of experience building projects like this. In fact, the more experience you have, the more you understand how easy it is to make mistakes.


More information about using the trigger follows.


AC/DC adapter


You don't have to remove the battery if you're powering the unit with the optional AC/DC adapter or with any AC/DC adapter that has the appropriate plug and an output from 6V to 12VDC. The battery is automatically bypassed when the AC/DC adapter plug is inserted in the jack. The unit should then work the same as when running on battery power.


Adjusting sensitivity


The sensitivity of the sound trigger is increased by turning the SENS knob clockwise.


Using the pulse output


Some flash units require a low voltage pulse for discharge. Use the pulse (P) output for such flash units.


Connecting to a delay unit


For most situations, the delay is adjusted according to the distance between the source of the sound and the microphone. Sound travels about a foot (third of a meter) in a thousandth of a second. By moving the microphone an inch at a time toward or away from the source of the sound, you can adjust the delay by tenths of thousandths of a second. In situations where you need a particularly long delay, it's more convenient to use an electronic delay unit. The delay unit circuit can be used. Connect the switch output of the sound trigger to the input of the delay unit. For a Multi-Trigger enclosure, for example, you would connect to the external input. For a Multi-Trigger breadboard, you would connect to 13F and ground.


Using other microphones


Other types of microphones such as dynamic and condensor microphones will work with the sound trigger. Connect them to the sound trigger with a 3.5mm mono jack. You may find, though, that the piezoelectric microphone works best.



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