simple circuit board construction and supply the following parts
B1: Filament type incandescent buib1 6.3V .075A type 7377 (Ballast & current limiter.)
Relay: 5', 50 coil, PCB mount DPDT; Selecta Switch SR15P207D1.
D3 & D4: Zener Diodes, 18V 2 watt NTE 5027A.
R5: 100k2 watt linear potentiometer; Caltronics P-68 or equiv.
LED I & 2, combined as Bicolor red & green In same housing, Radio Shack # 276-012
SW2: "Test" SPST momentary on submlniature push-button, Radio Shack # 275-1571
Do not expect this device to function optimally If ANY electrical changes or ego Improvements are attempted.
7555 CMOS timer chip (generic) IC1 $1.80
100 k ohm 3 watt 5% resistor R 1 .07
1 meg 3 watt 5% resistor R 2 .07
2.2k 3 watt 5% resistor R 3 .07
1 k 3 watt 5% resistor R 4 .07
100k linear taper pot, ½ watt Caltronics P-68 R 5 2.56
200 F 20 V (or higher) electrolytic capacitor C 1 .45
0.22 F 20 V (or higher) Tantalum capacitor C 2 .25
1N4001 diode 2 required @ .15 D 1 & D 2 .30
18Volt Zener diodes, ½ watt, 2 @ .79 D 3 & D 4 1.58 (NTE5027A)
NPN Transistor, generic 2N2222 Q1 .30
Bulb, 6.3 V .075A type 7377 B1 1.34
Relay, 5 V 50coil PCB Mount DPDT Selecta Switch SR15P207D1 5.45
Misc. wire, solder, etc. .50
Bicolor LED red/green Radio Shack #276-012 LED 1 $ 1.19
Jack for electrode leads 274-251 #/$1.59 J 1 .53
DPDT switch, 275-626 or equiv. (Used as DPST) SW 1 2.55
SPST Submini momentary push button switch SW 2 .59 ER-SW101 “Test”
Battery Holder, 4-AA cells, Radio Shack 270-383 1.29
4 Alkaline AA cell batteries, #23-552 4 for 2.89
3 Alkaline 9V batteries, type 1604 etc. 3 for 3.75
3 9V battery snaps (clip-on connectors) #270-325 pkg 5/$1.29 1.29
Box, if used 2.29
Above items generally available at local Radio Shack Stores
Lead wire with 3.5 mm plug, 6 ft., Mouser or Calrad Electronics .35
Electrodes, stretch elastic, Velcro, cotton flannel, alligator clips, etc ± 5.00 (See Notes)
Total Cost for all components for do-it-yourself project $ 49.24
This design is basically a 7555 IC timer chip set for 50% duty cycle and ~3.9 Hz driving a subminature relay.
Electrode polarity continually reverses ~¼ second positive / ¼ second negative. Frequency is not critical.
Dear employer,
my name is Ino, I am from Europe and currently living in China, working as sourcing agent for clients from USA and Europe. I also do quality control for them before shipment. I have experience in various fields and sourcing experience since 2002.
If you have time please send me private message so we can discuss more details.
Best regards
Ino Topalovic