Set up in 1999, Deland Car Accessories Co., Ltd. is a professional China 7805 regulator manufacturer and designer. It has years of OES and OEM 7805 voltage regulator production experiences and passed ISO9000 and the TUV certification of ISO/TS16949 quality system. Therefore, we can better fulfill customers' specifications and satisfy their changing needs, such as Ford, Opel, Benz, BMW, Nissan, Toyota, Mitsubishi, Mazda, Isuzu, Hyundai, Kia and Truck series.

* Vout: +5 V * Vin: +7 V min, +35 V max * Iout: 1 A * Case style: TO-220
Since the PIC doesn't have enough pins to run each segment of the display (all 96 of them) directly, the display is multiplexed. Only one digit is displayed at a time, but the digits are cycled through quickly enough to give the impression of a continuous display. I gave each digit a common cathode, and each segment of all the digits a common anode. The eight anodes (one for each of 7 segments, plus the decimal point) are connected via current-limiting resistors to output pins on the PIC. The 12 cathodes are connected to ground through standard NPN transistors (I used 2N3904) controlled by further output pins, since the PIC cannot sink enough current to connect the cathodes directly. Multiplexing with PICs is described by Microchip's Application Note AN557, which uses a 50Hz refresh rate for the multiplexed displays. I found this rather flickery, so used 80Hz, which corresponds to an on-time of just over 1ms for each digit.

The top portion of the schematic is a basic 5 volt power supply. Current draw of the CMOS timer is very low, so a small 120/12 volt transformer can be used. I mounted the 7805 regulator in a heat sink (see picture at right) but it probably isn't necessary. Switch SW1 turns the timer circuit on and off. CMOS 4528 is a dual monostable multivibrator (English translation: two timers in one). As drawn below, the left side controls the spacing between fog pulses and the right side sets the length of the fog pulse. These times are set by the r/c components attached to pins 2 and 14 respectively. The spacing times range from about 8 to 50 seconds (adjustable with pot R1) while the pulse length times are about 1 to 10 seconds (adjustable with pot R3).
Resistors R2 and R4 set the minimum times. The normally open switch terminals of relay K1 are wired to the fogger pump circuit. In the above mentioned fogger, the pump current draw is only 500 ma (1/2 amp) so a relay with 1 amp rated terminals will work fine (I used a minature realy from All-Electronics #RLY-405. It's the little green thing on the circuit board). The relay is wired across the terminals on the fogger remote connector that go to the switch on the remote. These can be found using an omhmeter across the pins on the remote and pushing the remote button.