Search found 100 matches
- Mon Nov 20, 2017 3:33 am
- Forum: Lighting & Electronics
- Topic: Why is my 555 timer not blinking?
- Replies: 30
- Views: 385398
Re: Why is my 555 timer not blinking?
I can only think that perhaps the diode is polarized and that I have it in backwards. The whole point of a diode is it is polarised. it's purpose is to let current flow in one direction but not the other. It's worth doing some reading up on basic component symbols because these will always indicate...
- Thu Nov 02, 2017 3:36 am
- Forum: Lighting & Electronics
- Topic: PCB design
- Replies: 8
- Views: 28066
Re: PCB design
PM'd
- Fri Oct 20, 2017 2:37 am
- Forum: Lighting & Electronics
- Topic: Picking a power supply
- Replies: 4
- Views: 16450
Re: Picking a power supply
Factor a 3.2v forward voltage for the whites, with the greens it's a bit harder to guess because there are different types. Older traditional greeny-yellows have a Vf of around 2v, but more modern pure greens are more likely to be around 3v. Start with 2v and see how that looks. Assume a max operati...
- Wed Sep 13, 2017 2:21 am
- Forum: Construction
- Topic: Drilling Really Tiny Holes?
- Replies: 20
- Views: 70620
Re: Drilling Really Tiny Holes?
I made myself a mini drill from a 12v motor & 600RPM gearbox combo, and miniature chuck, both from ebay for a total of less than 5 quid that I have been using with 0.5mm drills on my Zvezda SD and haven't broken a drill yet. It's fast enough to drill a hole in a couple of seconds, but not fast e...
- Wed Sep 13, 2017 1:59 am
- Forum: Lighting & Electronics
- Topic: Connecting Circuits (boards) to the same Power Supply
- Replies: 2
- Views: 10547
Re: Connecting Circuits (boards) to the same Power Supply
Hi all! Like the title says, when connecting several different blinking circuits (boards) to the same power supply, the boards are connected in parallel - right? Right. Each module or board is a complete circuit in its own right and will have a current draw as defined by that circuit. Provided that...
- Sat Sep 02, 2017 1:50 am
- Forum: Lighting & Electronics
- Topic: Rotating Police Strobe Lights Effect
- Replies: 15
- Views: 37628
Re: Rotating Police Strobe Lights Effect
I've done something like this, but will echo the comments that it is extremely fiddly!! it was only one beacon, and was driven by a microcontroller, but I did manage to get a light cluster around the size of a 5mm LED. 1st Prototypes https://vimeo.com/129956163 Final go https://vimeo.com/130010713 T...
- Thu Aug 31, 2017 11:35 am
- Forum: Lighting & Electronics
- Topic: Powering LEDs without resistors
- Replies: 5
- Views: 13782
Re: Powering LEDs without resistors
I'm currently planning a project and I'm wondering, purely for ease of soldering, if I can get away with not using resistors for my LEDs. Short answer. No Long answer. LEDs are current devices. The current must be limited to specified values or the device will fail. Without any limits, the more vol...
- Wed Aug 30, 2017 2:41 am
- Forum: Lighting & Electronics
- Topic: 3 mm LED lights Series or Parallel
- Replies: 9
- Views: 19440
Re: 3 mm LED lights Series or Parallel
There is absolutely no problem with using one method (series / parallel) over the other, *provided* the specification of the devices are respected. If your circuit is designed correctly, you will get a lifetime of use. LEDs just randomly failing or "burning out" under correct operational p...
- Sun Aug 20, 2017 2:00 am
- Forum: Lighting & Electronics
- Topic: 3 mm LED lights Series or Parallel
- Replies: 9
- Views: 19440
Re: 3 mm LED lights Series or Parallel
In series, one resistor per set of LEDs.
In parallel, one resistor for each LED.
In parallel, one resistor for each LED.
- Tue Aug 08, 2017 2:27 am
- Forum: Lighting & Electronics
- Topic: LEDs & Other Low voltage, Low power lighting
- Replies: 52
- Views: 189258
Re: LEDs & Other Low voltage, Low power lighting
The flash rate of flashing LEDs is fixed and usually around once a second (1 Hz - Hertz is the unit of frequency. 1 Hz = 1 oscillation per second. 100Hz = 100 oscillations per second) is the 3mm to big in diameter, or too tall? If it's too tall, you might want to look at SMDs in a PLCC-2 package. Th...
- Wed Aug 02, 2017 2:09 am
- Forum: Lighting & Electronics
- Topic: Black Hole's V.I.N.CENT MPC model lighting kit
- Replies: 2
- Views: 6500
Re: Black Hole's V.I.N.CENT MPC model lighting kit
Yeah that controller board looks like major overkill, although I get the impression that's just a generic driver with far greater capabilities.
- Sat Jul 15, 2017 12:00 pm
- Forum: Lighting & Electronics
- Topic: Source For Ultra High Quality LEDs???
- Replies: 14
- Views: 26773
Re: Source For Ultra High Quality LEDs???
White LEDs are just blue LEDs shining on a phosphorous that emits white - there's no reason they should be any less reliable providing they are run within spec...
- Fri Jul 14, 2017 4:11 am
- Forum: Lighting & Electronics
- Topic: Source For Ultra High Quality LEDs???
- Replies: 14
- Views: 26773
Re: Source For Ultra High Quality LEDs???
You will probably have to buy the LEDs yourself from a proper component supplier (not ebay) who specify what they sell, and them wire them yourself. Otherwise you're going to be at the mercy of the bottom line...
- Wed Sep 28, 2016 1:49 am
- Forum: Lighting & Electronics
- Topic: Batteries drained in 2-3 days despite LEDs being off?
- Replies: 2
- Views: 5658
Yes, the wireless controller will be drawing some current all the time, which will drain the batteries. Coupled with that, the CR2032 cells have very little capacity and are not intended for 'always on' circuits unless the draw is down in the micro amp range. A 9v would give you a bit longer life, b...
- Sat Sep 10, 2016 12:42 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Wed Sep 07, 2016 11:37 am
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Tue Sep 06, 2016 1:07 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Tue Sep 06, 2016 7:00 am
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
It would be much easier if I could post some diagrams - at work at the moment so a bit difficult, but will try later. In the configuration you have, it's more likely to fail in the microseconds when power is applied, and as the diodes start to conduct and minute differences in the semiconductor prop...
- Tue Sep 06, 2016 2:33 am
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
I had posted a question here about where the resistors go, and the response I got was that it does not matter where the resistors go, but that they ought to go before the LEDs. There's no ought to - it makes no functional difference whatsoever. It's just a matter of personal preference. If you real...
- Mon Sep 05, 2016 12:38 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Mon Sep 05, 2016 7:14 am
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Fri Aug 26, 2016 1:09 am
- Forum: Scratchbuilding
- Topic: Excellent PE demo video
- Replies: 3
- Views: 12187
- Sun Aug 21, 2016 12:16 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
- Thu Aug 18, 2016 2:44 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
LRV08 is an equivalent to A23, so you're looking at a 50mAH capacity still. Adding a second battery in series will do nothing to increase that. I'll try and explain what you are seeing in your experiments. We'll assume your particular LEDs have a forward voltage of 3.5v which is typical. This is a p...
- Thu Aug 18, 2016 1:37 am
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
That's not a great article - it's written by someone learning to use LEDs but perpetuates several misconceptions, particularly the use or misuse of resistors in parallel circuits. The rule on that is simple. ALWAYS use a separate resistor with each parallel LED. IGNORE anything else you read. Not us...
- Wed Aug 17, 2016 12:36 pm
- Forum: Lighting & Electronics
- Topic: Shouldn't 12v be enough for seven 3mm LEDs?
- Replies: 31
- Views: 55736
Blue LEDs have a typical forward voltage of 3-3.5V, which means they won't be fully conducting until there is at least that potential across them. You will start to get some current flow at lower voltages - if you're getting some light with 5 but none with 6 then conduction is starting between 2v an...
- Sun Aug 14, 2016 2:08 pm
- Forum: Lighting & Electronics
- Topic: Powering LEDs with 3.7v Lipo
- Replies: 3
- Views: 6765
You need to be much more careful when using LiPos as many do not have any overcharge/overdischarge/short circuit protection built in and rely on it being provided by the circuit they are powering. At best misuse may permanently damage the cell, at worse it could catch fire or explode! Unless you are...
- Thu Aug 04, 2016 11:47 am
- Forum: Lighting & Electronics
- Topic: 3V LED Strip lights???
- Replies: 9
- Views: 23577
- Fri Jul 01, 2016 9:29 am
- Forum: Construction
- Topic: TARS/CASE in 1/72 what size?
- Replies: 3
- Views: 9886
- Mon Feb 08, 2016 4:35 am
- Forum: Lighting & Electronics
- Topic: Switching from AAA to AA batteries
- Replies: 6
- Views: 12546