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Are these circuit diagrams correct??

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cobra1

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Have designed these circuits, just want to check and see if there is anything more that needs adding??
i have built it on vero board and it works great, just want to make sure theres nothing missing.

Especially the power supply part

154-StartupCircuit.jpg


155-MainCircuit.jpg
 
OK, so far i have had comments on the transistors driving the leds. I have been told these are not required when using leds so i will remove them from the schematic
 
The 470 ohm resistors will limit the LED current to 2V red LEDs only about 4.7mA with or without the transistors so they will look fairly dim.
Since the transistors are emitter-followers and have useless base resistors the relays will get only about 3V so they will not work.
 
using the schematic above, i have built this on vero board and all relays are working fine and leds look fairly bright (red diffused leds)

EDIT: i just checked the pinouts for the transistors i am using, it appears i have installed them all the wrong way round, so my outputs (leds, relays) are on the collector side going high. The emitters are straight to 0v

does this make a difference??
 
Last edited:
DIT: i just checked the pinouts for the transistors i am using, it appears i have installed them all the wrong way round, so my outputs (leds, relays) are on the collector side going high. The emitters are straight to 0v

does this make a difference??
Then the transistors turn on with a 0.1V loss instead of a 0.8V loss so the LEDs will be a little brighter.
 
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