AVR-Chat

While the topic of displays is active, any interesting low-budget 
solutions of large outdoor readable displays? Digits have to be at 
least 2" high. Would really like to have one of those florescent dot 
displays which many businesses use on their street signs, but can't 
afford one. At least not a new one.

In Hare Scrambles (and similar) motorcycle races we usually use barcode 
stickers on the helmet to score. Rider enters a tent (barcode reads 
best in the shade) to be scanned then the rider zooms out. The scoring 
computer instantly knows his position but the idea is to have a display 
suitable for showing it to the rider.

This is me, on the motorcycle, getting scored: http://tinyurl.com/25z87

--
David Kelly N4HHE, dkelly@HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.

I bought some, I think it was 114 mm high, red 7 seg displays from Farnell 
to make a custom display for showing result times at a race track. I knew
it would be hard to see, so I drove them pretty hard, and when I first 
turned them on in the circuit at home, I was blinded. They were insanely
bright.
Next weekend on the track, it was a great day, the sun was on and I 
brought my new display. It was totally invisible in the sun !! You couldn't
see anything ! Not even up close.
So - try to get that fluorecent displays if possible in any way, it is by 
far the best technique. Or perhaps a 7 segment display made by ultra 
high brightness LED's could be used.

/Jesper


----- Original Message ----- 

From: "David Kelly" <dkelly@hiwaay.net>
To: <AVR-Chat@yahoogroups.com>
Sent: Sunday, April 10, 2005 6:22 PM
Subject: [AVR-Chat] Really Big Outdoor-readable Displays?


> 
> While the topic of displays is active, any interesting low-budget 
> solutions of large outdoor readable displays? Digits have to be at 
> least 2" high. Would really like to have one of those florescent dot 
> displays which many businesses use on their street signs, but can't 
> afford one. At least not a new one.
> 
> In Hare Scrambles (and similar) motorcycle races we usually use barcode 
> stickers on the helmet to score. Rider enters a tent (barcode reads 
> best in the shade) to be scanned then the rider zooms out. The scoring 
> computer instantly knows his position but the idea is to have a display 
> suitable for showing it to the rider.
> 
> This is me, on the motorcycle, getting scored: http://tinyurl.com/25z87
> 
> --
> David Kelly N4HHE, dkelly@HiWAAY.net
> ========================================================================
> Whom computers would destroy, they must first drive mad.
> 
> 
> 
> 
> Yahoo! Groups Links
> 
> 
> 
> 
> 
> 
> 
>

A few ideas...

- Use a large reflective-substrate LCD?

- Get an off-the-shelf outdoor LED display?
http://www.spectra-displays.co.uk/32.php

- Watch for a surplus display from a city bus, the electromechanical
type where the segments or pixels are actually florescent dots that are
flipped over?

Best Regards,
Dave

On Sun, 2005-04-10 at 11:22 -0500, David Kelly wrote:
> While the topic of displays is active, any interesting low-budget 
> solutions of large outdoor readable displays? Digits have to be at 
> least 2" high. Would really like to have one of those florescent dot 
> displays which many businesses use on their street signs, but can't 
> afford one. At least not a new one.
> 
> In Hare Scrambles (and similar) motorcycle races we usually use barcode 
> stickers on the helmet to score. Rider enters a tent (barcode reads 
> best in the shade) to be scanned then the rider zooms out. The scoring 
> computer instantly knows his position but the idea is to have a display 
> suitable for showing it to the rider.
> 
> This is me, on the motorcycle, getting scored: http://tinyurl.com/25z87
> 
> --
> David Kelly N4HHE, dkelly@HiWAAY.net
> ========================================================================
> Whom computers would destroy, they must first drive mad.
> 
> 
> 
>  
> Yahoo! Groups Links
> 
> 
> 
>  
> 
> 
>

Jesper Hansen wrote:
> I bought some, I think it was 114 mm high, red 7 seg displays from Farnell 
> to make a custom display for showing result times at a race track. I knew
> it would be hard to see, so I drove them pretty hard, and when I first 
> turned them on in the circuit at home, I was blinded. They were insanely
> bright.
> Next weekend on the track, it was a great day, the sun was on and I 
> brought my new display. It was totally invisible in the sun !! You couldn't
> see anything ! Not even up close.
> So - try to get that fluorecent displays if possible in any way, it is by 
> far the best technique. Or perhaps a 7 segment display made by ultra 
> high brightness LED's could be used.
> 
> /Jesper

Sign jobs are more of a problem in mechanics. Build a sloping roof/shroud
to cast a shadow over the display. Cover the display with coloured plastic
to increase the contrast.

If you're serious, a good mechanical 7 segment display is what you 
need. Like this maybe:

http://www.bodet.com/urlref/01a8cata/urlext/asp/produit/prod/216/rub/7/produit.htm

Peter

Russell Shaw wrote:

> Sign jobs are more of a problem in mechanics. Build a sloping roof/shroud
> to cast a shadow over the display. Cover the display with coloured plastic
> to increase the contrast.

On Apr 10, 2005, at 8:22 PM, Peter Gargano wrote:

> If you're serious, a good mechanical 7 segment display is what you
> need. Like this maybe:
>
> http://www.bodet.com/urlref/01a8cata/urlext/asp/produit/prod/216/rub/ 
> 7/produit.htm

Exactly. So how can I get something like that cheap? (stealing it off  
the bank's street sign doesn't count.) Didn't find prices at Bodet.com  
so I can only presume, "If one has to ask, one can not afford it."

--
David Kelly N4HHE, dkelly@HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.

On Apr 10, 2005, at 9:32 PM, Roy E. Burrage wrote:

>  With a drill press, a 19 inch relay rack panel, and some incandescent 
> displays you can do it for not a whole lot of money.  It may be a bit 
> time consuming but it's also visible in daylight.  If you multiplex 
> segments you might also want to use isolation diodes for each segment.

Have thought of building my own using Christmas tree pixie lights and 
triac drivers. OTOH this application is run off a battery. Usually a 
car battery to ensure a laptop also stays powered. If the scoring 
system fails one suddenly has 300 upset riders, no matter that a manual 
backup is kept.

--
David Kelly N4HHE, dkelly@HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.

On Sun, 2005-04-10 at 22:12 -0500, David Kelly wrote:

> Have thought of building my own using Christmas tree pixie lights and 
> triac drivers. OTOH this application is run off a battery. Usually a 
> car battery to ensure a laptop also stays powered. If the scoring 
> system fails one suddenly has 300 upset riders, no matter that a manual 
> backup is kept.

This might seem a little far-fetched, but it would allow you to use 100%
off-the-shelf hardware... What about a receipt printer? You could set up
the software to automatically print out a receipt with the rider's name
and time as soon as his/her barcode is scanned...

Heck, if you wanted to take this a little further you could get a
surplus outdoor printer like the ones at parking garages, and have it
spit out a ticket as they ride out of the tent...

Dave

David Kelly wrote:
> While the topic of displays is active, any interesting low-budget 
> solutions of large outdoor readable displays? Digits have to be at 
> least 2" high. Would really like to have one of those florescent dot 
> displays which many businesses use on their street signs, but can't 
> afford one. At least not a new one.
> 
> In Hare Scrambles (and similar) motorcycle races we usually use barcode 
> stickers on the helmet to score. Rider enters a tent (barcode reads 
> best in the shade) to be scanned then the rider zooms out. The scoring 
> computer instantly knows his position but the idea is to have a display 
> suitable for showing it to the rider.
> 
> This is me, on the motorcycle, getting scored: http://tinyurl.com/25z87
> 
> --
> David Kelly N4HHE, dkelly@HiWAAY.net

I have built many displays for Rally Australia under contract, and I can 
assure you that if the display has a weather shield over the top, and 
the digits are high effeciancy, with red perspex cover, they ARE 
readable in daylight, I drive my displays with ULN2803's, and the 
current is set to around 30mA (not even close to their maximum) I use 
only Kingbright displays, usually 50 or 100mm high digits. If you need 
part numbers I can dig them up :)

Regards,

Kat.