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页码 24
DN1 
• 13  
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11. Install R1, 1K ohm [brown-black-red]. 
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11. Install Q1, the power FET transistor [marked 7035]. Form the leads 
as shown prior to 
installation. Bolt the 
regulator to the circuit 
board. 
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12. Install L1,  the large 
axial leaded wire wound 
inductor. 
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13. Install D1, 1N4937 fast 
recovery diode. Observe the correct polarity! Note also that this is 
another “stand up” diode, so form the leads as before for a proper fit. 
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14. Identify Q2, a 2N3904 NPN transistor. When installing  Q2, observe 
correct placement of the flat side. Press the transistor  snugly into the 
PC board so that only a minimum amount of wire  lead is exposed above 
the board. In soldering, do not be afraid of  using enough heat to make a 
good solid connection. 
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15. Install R9, 1K ohm [brown-black-red]. 
That’s it for the switching high current supply! This part of the circuit provides 
the “muscle” to charge the batteries.  
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16. Install LED D3. This component is polarized and must be oriented 
correctly. Examine the LED and notice how one lead is longer than the 
other. Most diodes also have a flat mold in one side of the component 
body. This flat side is on the same side as the shorter leg.  When 
properly installed, the flat side should face towards S2. Leave the diode 
leads as long as possible, because this component will mount to the 
front panel as a charging status indicator. 
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17. Using scrap component lead, form a “jumper” wire and install it in the 
JMP2 position. A jumper acts as an electronic bridge to carry power and 
signal over the traces run underneath. 
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18. Form and install another jumper, JMP1. 
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19. Install R7, 470 ohm [yellow-violet-brown]. 
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20. Install R12, 270 ohm [red-violet-brown]. 
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21. Install R14, 17.8K ohm 1% [brown-violet-grey-red]. 
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22. Install R16, 10K ohm 1% [brown-black-black-red]. 
Power FET 
Tab 
Solder Connections
 
PC Board
LED
Leave these leads 
as long as possible
(+)
(-)