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Assembly and Operating Instructions for HiViz.com Kits

 

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Schmitt Trigger Photogate Upgrade Kit (PGU)

 

Note: These instructions are for kits before v10.

 

Assembly instructions

 

This kit includes parts to make upgrades to an SPG1-DU-BB or SPG2-DU-BB kit. Parts included are these:

 

2 red LEDs
1 100-Ω resistor
2 470-Ω resistors
100-kΩ potentiometer (brown knob)
Jumper wire

 

We assume you’re starting with an existing SPG1-DU-BB or SPG2-DU-BB wired like the one here.

 

Here's a photo of the circuit before upgrades. Click on the photo for an enlargement.

 

bb_054.jpg (2838410 bytes)

 

Below are the wiring instructions for the upgrades:

 

Photogate indicator light

  1. Connect one of the 470-Ω resistors from 5H to 10H.

  2. Connect the shorter leg of one of the red LEDs to 10J and the longer leg to the red (+9 V) column.

Function: When the photogate beam is unbroken, the LED will be lit. When the beam is interrupted, the LED will go out. This allows you to check the function of your photogate without having a flash unit connected.

 

Delay unit indicator light

  1. Connect the other 470-Ω resistor from 22B to the nearest red column. (That’s the red column next to the blue ground column.)

  2. Connect the shorter leg of one of the red LEDs to the blue ground column and the longer leg to the adjacent red column.

Function: When the delayed output of the delay unit is triggered, the LED will light momentarily after whatever delay you’ve dialed in.* This allows you to test the function of the delay unit without having a flash unit connected. If you wish to test the immediate output of the delay unit, move one end of the resistor from 22B to 19A.

 

*The LED will remain on for a length of time determined by the value of the resistor between 26B and 30B. The time that the LED remains on is approximately the value of this resistor in kilohms divided by 100. The value of the resistor shown in the photo is 1 kΩ. Therefore, the LED remains only about a hundredth of a second. If the resistor is replaced with a 100-kΩ resistor, the LED will remain on for about a second. During this time, the delay unit cannot be triggered.

 

Fine delay control

  1. Place the 100-kΩ pot with the middle leg in the blue column next to the red +9-V column and with the other legs in 13I and 15I.

  2. If the 0.5-µf capacitor currently goes from 25J to 27J, remove it and connect it across 27I and 29I. The negative side of the capacitor must be in 29I.

  3. Locate the 100-Ω resistor currently in the circuit from 26H to 30H. Remove the leg in 30H and place it in the blue column next to the red +9-V column. (An extra 100-Ω resistor is supplied with this upgrade kit in case you need to replace the current resistor.)

  4. Run a jumper wire from 30H to 15H.

Function: The 100-kΩ potentiometer allows one to make fine adjustments to the time delay. Coarse adjustments are made with the 1-MΩ potentiometer.

 

Click below for enlarged photos of the upgraded circuit.

 

 

Assembly instructions for other kits

 

 

 


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