Hobbyist, yes, I want to be able to toggle on and off the flashing of the LEDs and have them remain lit when the flashing pulse is off or otherwise removed.
Audioguru, I see what you are saying. Particularly last night when I added the pull-up resistor which prevented the LEDs from going fully off during pulses. That came as a big duh. Should've seen that sooner.
Well, I added a transistor to the ground portion of the 555 flasher so I could turn the flasher on and off and, for better or worse, I noticed the 555 outputs a steady high signal (didn't measure, but I assume 4-5V) with the transistor turned off. See attachment. This kept the LEDs on when the flasher was off which is my goal. However, I don't know why this is the case and don't feel it to be the safest method, so I'm going to try Hobbyist's circuit this weekend. In effect, I think I'm looking for a SPDT which looks like it can be accomplished with two transistors.
One question regarding the circuit in the attachment - I measured just less than 280mA between the common cathode of the LEDs and the collector pin, but the 2N2222 transistor was very hot to the touch. The 2N2222 is rated, I thought, to at least 600mA. Should I use a transistor with a higher current rating like a TIP or is there another problem I've overlooked?
Thank you, thank you, and thank you again everyone. I immensely appreciate the help.
Audioguru, I see what you are saying. Particularly last night when I added the pull-up resistor which prevented the LEDs from going fully off during pulses. That came as a big duh. Should've seen that sooner.
Well, I added a transistor to the ground portion of the 555 flasher so I could turn the flasher on and off and, for better or worse, I noticed the 555 outputs a steady high signal (didn't measure, but I assume 4-5V) with the transistor turned off. See attachment. This kept the LEDs on when the flasher was off which is my goal. However, I don't know why this is the case and don't feel it to be the safest method, so I'm going to try Hobbyist's circuit this weekend. In effect, I think I'm looking for a SPDT which looks like it can be accomplished with two transistors.
One question regarding the circuit in the attachment - I measured just less than 280mA between the common cathode of the LEDs and the collector pin, but the 2N2222 transistor was very hot to the touch. The 2N2222 is rated, I thought, to at least 600mA. Should I use a transistor with a higher current rating like a TIP or is there another problem I've overlooked?
Thank you, thank you, and thank you again everyone. I immensely appreciate the help.
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