Let there be LIGHT! Useful (Red) LED Lightsource.

[Macavity]

Recently, I have been "lighting up" various mounts, with the aid of a couple of standard items available from MAPLIN UK (I have no commercial interest in this):

L90AN 9v (PP3 type) SWITCHABLE battery box

N04CG Constant current source + single red LED

For those with some modest soldering iron skills, these are an attractive solution. This will pump a constant 30mA through (one or more) red LED's from (whatever) battery source. Basically, I wanted a compact thing, with few discrete components, providing fixed, LOW-LEVEL RED (potentially rechargable!) lighting over ~8 hours, for setting circles etc. THIS setup does the job rather well for me.

Might work for "hazard-flashers" too - W/Flashing LEDs?

[geppetto]

Very useful they are too Chris.

I've got these light fitted to all my scope setting circles.

Slightly easier way is to use two 1.5volt AA batteries and a Maplin high brightness

3 volt red LED.

[Macavity]

Sounds GOOD, Philip! - 'S long as you're not (seen as) a "hazard to shipping" or something. :sunny:

Aside: Something I have always been after is an IDEA re. the typical Red Dot Finder. I leave these ON, far to often, thereby flattening a LOT of CR2032 cells. Thre is SOME (little) room inside the RDF housing for small components. Or maybe something bigger and external? A micro-swich, delay timer, a "cable release" thingy - Ideas always welcome...

[geppetto]

Yes, I keep wasting those batteries as well

Hmmmm.. a 555 timer and a small relay set to switch off after 60 seconds or so...

Right, it's in my scribble book for a rainy day

[GordonCopestake]

[fires up crocodile clips]

[Ambermile]

Oh boy am I going to be in trouble next time the beast goes out to play... It happened like this:

I had two 5" fans under the mirror and just a couple of wires poking out that I twist on to a battery to cool the mirror. Last night I decided to bite the bullet and install a 12v socket on the side of the box ( drill that paint job!) While I was in there doing this I thought it might be an idea to have an LED as wel to let me know the fans were on as they are pretty much silent running. Then I thought that maybe having a light on the side would not be a good idea as I was using a 12v LED. So, obviously, stick one *under* the mirror box! Brilliant! Then, I thought that maybe if I was the other side I'd not see it. So, stick one at each corner, under the box so I can see it from wherever I am... Nice idea so I got on with it. Finally get around to a test and all looks OK but then I turned the workshop lights out... Looks like the shuttle getting ready to ignite! Never realised just how bright those 5mm 12v LEDs were...

Arthur

[JohnC]

What next Arthur....saw an american dob with a cup holder attatched for a hot toddy on those cold nights.

[Jaffa007]

I found & bought, the CR2025 types on ebay really cheep!

Pack of 10 for £3 max [inc P&P], for those forgetfull red dot owners 8)

[Ambermile]

What next Arthur....saw an american dob with a cup holder attatched for a hot toddy on those cold nights.

Well, I thought of a cigar lighter socket actually... since I'm one of those dirty stop-outs that still insist on smoking. Might save my night vision! Trouble is, the CD player would slow down when I use the lighter...

Arthur

[Kaptain Klevtsov]

Anybody know if the car fag lighter will work in a power tank? I was going to have a go and then forgot.

Captain Chaos

[magician]

When I replace the Lens cap back onto my ETX90 there is the sticker saying" Turn The Dot OFF!"saves clever electrics, --you can,t beat talking to yourself-