Not sure if I am supposed to put up subjects like this here but at I have searched everywhere and can only find a supplier in China. The postage makes them almost double the price.
This is what I'm looking for.
Question:
Does anyone know where I can get these digits either here in the UK or anywhere else?
Many thanks in advance
Warren
Hi Warren, long time no hear.
Racing season over again?
Have you considered using LED strips as the LED segments vs a 7-segment display?
Maybe that is more procurable locally for you.
The biggest "7 segment" display I see at Farnell.com with Ireland selected is 4".
vs
http://ie.farnell.com/omc/ffsy1/led-flexstrip-top-yellow/dp/1226697
where you put 3 or 6 LEDs per segment. Power from 12V, use TPIC6B595 to sink current to turn a segment on.
Hi Robert, great to hear from you again. Yes the season is coming to an end in the next couple of months.. we have a race this weekend and then we get ready for the Ulster Grand Prix the week after then 1 more race 1 month later to finish.
I already have the Sparkfun 6.5 digits which worked great but were not bright enough for outdoor use.
Is the flexistrip high brightness? It says "Luminous Flux @ Test: 54lm".. is this bright enough for outside? I don't see any other reference to brightness.
Cheers
Warren
If you look at the linked datasheet there is a table with ratings for 4m strips of each color, the white has a listed output of 120 lumens. However, that's probably tested with the strip extended, so shaped as a 7 segment display it may appear a bit brighter.
I don't know for sure Warren. You can search other LED strips & see what kind of brightnesses are available.
Or, make up your own segments with high brightness LEDS, like 10,000mcd to 15,000mcd. They are blindingly bright!
The Sparkfun digits are ~ 3000mcd per segment from 12 LEDs.
Six 10000mcd LEDs per segment would be way brighter.
For example:
http://ie.farnell.com/multicomp/ova-1081/led-superflux-large-dome-white/dp/1716729
If you are after high-visibility outdoors, wouldn't the rotating/flipping black/yellow displays be better. You often see them at petrol/gas stations. According to Wikipedia, they are called vane displays - http://en.wikipedia.org/wiki/Vane_display.
Where does one obtain vane displays?
Hmm. Good question. I didn't check before mentioning it. It appears that you can get them direct from manufacturers (like http://www.flipdots.com/electromagnetic-large-7-segment-display.html), but I couldn't find any retail sources on google. Even Ebay didn't turn anything up above one inch tall. Pity. They'd be good for a lot of outdoor stuff.
Thanks for the replies. 
I think the strip will cause too much work making segments etc.. possibly the best way forward is a gas/fuel sign 7 segment digit running 12 volts or something like that?
The vane displays are fantastic but way too pricey.. I looked into them before and even went to the bother of making an experimental electromagnet etc.. only to find that's not exactly how they work.. ah well, I had fun messing with them. Can't remember the price or even how they work but basically they were too expensive.
The image of the digit I used at the beginning of this thread is perfect for what I need, all the hard work is already done leaving me to simply connect and upload the programme. It's just the postage from China that's making me look a little closer to home.
I'm away for the weekend and will be back Sunday for any updates.
Warren
No, the strips are easy.
Cut off 3 or 6 LED, wire 1 lead to +12V, the other to a TPIC6B595 shift register pin.
Here's a board I have with 12 of them, this pic has 6 installed.
They look great Robert and I agree, they don't look like they would be too hard to put together.
How bright are they? Would they be suitable for outside in sunny weather like the gas price signs?
Let me ask the forum member who uses the LED strips for swim meets to chime in. He has some assembled, I'll see if can take an outdoors shot.
May have to wait until I can send him e-mail from home.
The pics I have seen were quite visible looking across a swimming pool with 12" digits.
At worst, can do 2 or 3 strips in parallel so have more LEDs lighting up per segment like the spark fun digits.
Maybe make a shroud to go around them some like a traffic light.
Or do a strip of custom board with whatever LED you wanted on them, such as these 5mm 10,000mcd LEDs.
http://www.mpja.com/5mm-White-LED-10000mcd-Non-Diffused/productinfo/17145+OP/
or these 15,000mcd LEDs
http://www.mpja.com/10mm-White-LED-15000-mcd-Non-Diffused/productinfo/15415+OP/
Warren,
I heard back from Greg, who is using the LED strips.
"They show up very well except in direct sunlight.
I just got in some where the LED ribbon is black with white 5200K led's I think they will work very well. White shows up the best especially the 5200-5600K.
Have him spend $15.00 on Ebay and order LED ribbon and he can test.
If they are on a block background you can see them in direct sunlight for at least 100' when the digits are 12" I haven't had a need to try farther."
That would be great. 100' in direct sunlight would do the job perfect. I'll have to get some ordered up and give them a try. I'll keep you informed of my next move. Won't be for a lot of weeks yet.. really busy with work n the racing at the minute, just finished the Ulster GP last week and now getting ready for our last meeting in 3 weeks.
Speak soon,
Warren
Hi Robert, it's been a while and lots have gone on. We have recently moved house and financially I am now in a position to proceed further with the lap board. The 7 segment digit I started this topic with has now finally been sourced, purchased and delivered (x 6) including buttons, wire, perspex, carbon fibre sticker material.. everything!
Question: The digits need min 14.4v to run. The best option I came up with is 2 x 9v batteries to give 18 volts which run the segments perfect. I know if I try to run 18v into the Arduino it will not like it so would I be correct in saying a 5v regulator will do the step down for me?
This is the one I have been looking at on Sparkfun/Protopic;
http://proto-pic.co.uk/voltage-regulator-5v/
Regards & happy new year!!
Warren
Hi Warren, welcome back.
Yes, but 18V down to 5V is likely to make the regulator pretty hot. Try to find a switching regulator if you can. Or make sure the regulator has a very good heatsink.
If you put 5V into the power header, be sure to add a diode from 5V (anode) to Vin (cathode) to avoid reverse driving the onboard regulator.
Thanks Robert.. the last thing I would want is for it to overheat. :~
Might add an extra battery compartment for some AA's to run the Arduino at 4 x 1.5v = 6volts and let the 2 x 9v batteries run the digits.. or would that be wrong? Would I still need the diode with this set up? What type/size?
Cheers Warren
Dual batteries would be a good solution.
If you can hack a USB cable and provide power via the USB connector, no diode is needed.
Otherwise, put one in to avoid risk of damage to regulator.
1N4001, 1N4002, not too critical.
Connect all grounds together with dual power sources.
Can also use a Promini for smaller size. I have 120 or 12 running with 5V into Vcc pin, no diode, power them about for a couple hours 4 times a week since Dec 2010, no issues.
You can make one out on the lower left side of the control board here, 12V comes in to a 5V regulator on one of the LED boards, it makes 5V and shares it with all 3 boards.
Hi Robert, I have been doing my research trying to learn about regulators and capacitors etc haha.. lots to learn!
I thought about the dual battery system and the regulator and I think the best way to go is the regulator for a couple of reasons.. cost and convenience. XD
Ok, if I use the 5 volt regulator (link above) and connect my 18 volts in and 5 volts out. I will need a Diode Rectifier - (1A 50V IN4001) to go across + & -.. is that correct? Will I still need the diode if I use the regulator and one power source?
I came across someone attaching a couple of Tantalum Bead Capacitor 1uF 25V to the input and output.. is this necessary? I will of course be using a heatsink.
Thanks again for your help.