JVC 330 Service Manual

Contents

Chapter 3---Service Adjustments3-22 Model 330, 340SC, 370SC Service Manual2. Measure the number of millivolts between pins 3 and 4 on SPS J505.NOTE: This circuit is designed so that the number of millivolts betweenthese pins (for Models 340 and 370, it is millivolts divided by 10)represents the lamp current in amps.3. Multiply the two (2) figures from Item 1 and from Item 2 together.4. Divide the product from Step 3 by 1 for Model 330 wattage. Divide theproduct from Step 3 by 10 to get wattage for Model 340SC or 370SC.5. Adjust the Lamp Current Adjust pot (see CAUTION below Table 3-1) onthe top of the SPS (refer to Figure 4-3) until this result is within theappropriate HJT model spec indicated in Table 3-1).Example (for Model 370SC): Voltage measured between J503 andJ504 = 28V and voltage measured between pins 3 and 4 of J505 =1070mv.The product of this is 29960÷10 = 2996W. This result is within the Model370SC spec of 3000W ± 25W and would not require adjustment.Table 3-2 Arc Lamp Current and Amp SpecsModel 330 Model 340SC Model 370SC1500 Watts ± 25W 2000 Watts ± 25W 3000 Watts ± 25W68 Amps Normal 80 Amps Normal 100 Amps Normal70 Amps Maximum 85 Amps Maximum 110 Amps MaximumCAUTION! Make adjustments in small increments to ensure lampintegrity (lamp overheating may occur if current is abruptly increased). Do notincrease the current beyond the maximum levels listed in Table 3-2.