Search found 75 matches
- Mon Oct 16, 2017 12:03 pm
- Forum: General Discussion
- Topic: Blinking red LED with a coin [button] cell
- Replies: 6
- Views: 4369
Re: Blinking red LED with a coin [button] cell
Yes I know - but that one(s) make sounds, don't last very long, and I just want to make it myself.
- Sun Oct 15, 2017 1:02 pm
- Forum: General Discussion
- Topic: Blinking red LED with a coin [button] cell
- Replies: 6
- Views: 4369
Re: Blinking red LED with a coin [button] cell
Thanks again dyarker, since this is still in the "brain-fart stage" the first attempt will probably go into a Tic Tac container [cut down] and filled with epoxy Just in case it falls off. I will hold it on with a double sided sticky tape. When I get it de-bugged I will post a picture. Than...
- Sat Oct 14, 2017 11:11 am
- Forum: General Discussion
- Topic: Blinking red LED with a coin [button] cell
- Replies: 6
- Views: 4369
Re: Blinking red LED with a coin [button] cell
Thank you for your reply. As I mentioned in my original post - there is room for two (stacked) no more than 1/4" high total. I will solder them.
Thanks again.
Thanks again.
- Sat Oct 14, 2017 6:31 am
- Forum: General Discussion
- Topic: Blinking red LED with a coin [button] cell
- Replies: 6
- Views: 4369
Blinking red LED with a coin [button] cell
Using an "off the shelf" red blinking 5mm LED [3v. 20 ma] and a small current limiting resistor controlled by a tilt switch (very simple so far) but since small size is very important I would like to power this with a coin cell [button cell] or two that are no larger than a quarter [25 cen...
- Mon Dec 15, 2014 1:46 pm
- Forum: Reader Projects
- Topic: I need help on using a transistor as a switch.
- Replies: 5
- Views: 17120
Re: I need help on using a transistor as a switch.
dyarker I tried both of your suguestions and both were correct. Option A - the gain was too low (exactly as you said) and it took touching the probes together to actually turn on Q3.
Then I did option B and it works perfectly.
Thanks again for the help. Much appreciated.
cNd
Then I did option B and it works perfectly.
Thanks again for the help. Much appreciated.
cNd
- Mon Dec 15, 2014 7:02 am
- Forum: Reader Projects
- Topic: I need help on using a transistor as a switch.
- Replies: 5
- Views: 17120
Re: I need help on using a transistor as a switch.
Thanks Dyarker for the info. I appreciate how in-depth you explained it.
- Sun Dec 14, 2014 6:00 pm
- Forum: Reader Projects
- Topic: I need help on using a transistor as a switch.
- Replies: 5
- Views: 17120
I need help on using a transistor as a switch.
fishclicker.jpg I've made several of these and they are called "fish callers". 9 volt battery operated, Put it in a sealed waterproof container like a pill bottle, add enough weight to cause it to sink, and with a string tied to it - drop it in and I can pull it back up. Works OK (didn't ...
- Wed Oct 29, 2014 6:58 am
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Re: Rare earth magnet and a 9 volt battery
Duct tape and plastic film?
- Sun Oct 19, 2014 6:47 am
- Forum: General Discussion
- Topic: 3V circuits.......
- Replies: 6
- Views: 3498
Re: 3V circuits.......
They are expensive but Lithium batteries should perform much longer.
- Thu Oct 16, 2014 9:23 am
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Re: Rare earth magnet and a 9 volt battery
OK, I just performed an extremely unscientific experiment. I just took two identical circuits with a 555 [astable mode] driving a 4017 decade counter/divider which in turn flashed [one at a time] 10 superbright LEDs. The flash rate was about 2 per second. Two new 9 volt batteries out of the same pac...
- Sun Oct 12, 2014 8:22 am
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Re: Rare earth magnet and a 9 volt battery
Thanks for the replies. I am going to go out on a limb here and draw a conclusion that has a 50/50 chance of being correct. Current problem: Whether to use Velcro or a rare earth magnet to secure a 9 volt battery in a hobby project built with parts that are + or - 5% to 10% within the specifications...
- Sat Oct 11, 2014 6:45 am
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Re: Rare earth magnet and a 9 volt battery
Tzap - thanks for the reply. I read the PDF and understood about half of it. LOL
I will do some "pondering" on it because I'm not sure what I just read.
I will do some "pondering" on it because I'm not sure what I just read.
- Fri Oct 10, 2014 6:17 pm
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Re: Rare earth magnet and a 9 volt battery
Thanks for your input hacklesup - I think I will try it.
- Fri Oct 10, 2014 3:01 pm
- Forum: General Discussion
- Topic: Rare earth magnet and a 9 volt battery
- Replies: 14
- Views: 9649
Rare earth magnet and a 9 volt battery
I'm working on a project with LEDs, 555 timers, resistors, and a couple caps. It will be powered by a 9 volt battery. Does anyone know if a rare earth magnet can be used to hold the battery in place? I know it will hold it - but will the magnet affect the battery life? It will require a battery chan...
- Fri Nov 08, 2013 5:57 am
- Forum: General Discussion
- Topic: Some transistor identification help needed.
- Replies: 3
- Views: 2443
Re: Some transistor identification help needed.
I made a mistake when trying to explain the circuit. I should have called it a Transistor shaped device. After considering that the entire dehydrator operated on 120vac that it obviously had to be a Triac.