My (probably not so) new idea for a diy pedal display

[ugly_guitar_guy]

http://www.youtube.com/watch?v=GpMSLAAib3U

It'll take up a little bit of space, but when hooked up to the 3rd section of a 3PDT switch it'll toggle back and forth between ON and OFF. This is going to go into the Fuzz Factory clone that I'm making for my father so that I can make fun of him for being an old man who needs a big display to see if the pedal is on or not.  This was so simple I might do it for more pedals if I can find blue 7 segment leds. I'm sure others have done this before, but I just figured this out so I was excited to share 

[frequencycentral]

I like it! A LOT!!

Do you have a schemo that you would share?

Thanks

[birt]

YOU ARE A GENIUS!

schematic is easy probably, you just have to figure out what led is connected to what pin of the display right?


but do i see an awful lot of resistors there? current limiters?

are the leds parallel then?

[Mark Hammer]

Don't you love it when spelling and 7-segment numeric displays cooperate?

Of course, it's a little "anglo-centric", but then if you can participate in this forum that shouldn't be an obstacle, right?

[frequencycentral]

Could you design one that says 'CLEAN' and DIRTY' ?!

[ugly_guitar_guy]

Here you go guys:



I just didn't feel like taking the time to make a pcb for this. It was easier to do on a pad per hole board. 25 x 1K resistors. They are in parallel. Glad I actually made a contribution guys! I thought this had probably already been done here before. I actually was looking for alphanumeric led's originally to make better looking words, but they are expensive. I think the "CLEAN" "DIRTY" idea is very cool, but would probably end up costing a lot of money. Also, this would probably be much easier with a 2 sided board and surface mount resistors...

[frequencycentral]

I think the "CLEAN" "DIRTY" idea is very cool, but would probably end up costing a lot of money.

Who cares about the money - this is about making pedals look cooler!

Also - I''m not a PCB guy, do you have a schmatic I could perf from? Thanks!

[ugly_guitar_guy]

I think the "CLEAN" "DIRTY" idea is very cool, but would probably end up costing a lot of money.

Who cares about the money - this is about making pedals look cooler!

Also - I''m not a PCB guy, do you have a schmatic I could perf from? Thanks!

Haha, very true. And that would definitely make for a cooler pedal.

As for a schematic, I didn't really make one. I found this site (http://www.play-hookey.com/digital/experiments/seven_seg_led.html) that showed me the pinouts for a 7 segment LED and then I breadboarded it to see if my idea would actually work. From there it was easier to make a pcb layout than a schem, but it's essentially just a bunch of led's with power run in parallel.

[birt]

i think you could have just paralled all the leds you needed for the word "on" and used only one current limiter and the same for "off" instead of using all those resistors. correct me if i'm wrong here.

oh and i'm definatly stealing your idea. sorry :p

[ugly_guitar_guy]

i think you could have just paralled all the leds you needed for the word "on" and used only one current limiter and the same for "off" instead of using all those resistors. correct me if i'm wrong here.

oh and i'm definatly stealing your idea. sorry :p

You know that thought crossed my mind but for some reason I didn't breadboard it just to see if it would work that way. I just went for the gusto, haha.

Haha, steal away. Just gimme a little credit for it now and then. 

[demonstar]

This is a great idea. I'm sorry to talk about the dark side but would it not be much easier with a digital pic or whatever those fangled digital chips are called?   

I bet this would look cool on the front of an amp head. Displaying Clean and Dirty as mentioned above.

[ugly_guitar_guy]

Also guys, an observation; The only "issue" that Ive encountered with this is a little bit of ghosting since the resistors are in parallel. For Example, when it says "OFF" you can see the lines that make up part of the N in "ON" are partially lit on the middle F. Also, when it says "ON" you can partially see the 2nd F of "OFF" getting a tiny bit of power. I dont know if there's a way around this, but it doesn't bother me enough to worry about it, I just thought I should offer that up in case anyone didn't notice.

[Incubus]

I once made something kind of similar, but also kind of not.

It was a "floor unit" that had 4 sets of 3 seven segment displays to show the words "ON" and "OFF" exactly as yours is. It also had 4 push-on push-off footswitches. Then there were 4 cables coming out of the unit going to 4 Boss pedals.....Distortion, Chorus, Flanger and Octaver. On the side of the boss pedals, I drilled a hole and riveted a 5 pin DIN connector.

The intention was to put the pedals on top of my amp and just have the footswitches at my feet. I then had to modify the flip-flop in the pedals so that instead of changing state with a momentary switch, it would actually be push-on push-off, to match the footswitcehs I was using.....they were easier to find.

For the seven segment displays, I used a high effieciency Hewlett Packard type which was a little pricey, but each segment only required 2ma, so that it could still be powered by the battery in the pedal without drawing too much current.

I've still got the pedals so I'll post a pic to show what it looks like.

When people see the pedals, at first they think it has midi

Oh.....and I ended up restoring the flip flops in the pedals to they're original condition.

[Incubus]

Here are a couple of pics......I forgot one of the pedals was actually a Boss Delay.

Second pic is a little out of focus but you'll get the idea.

http://img162.imagevenue.com/img.php?image=27880_IMG_0808_122_753lo.JPG

http://img221.imagevenue.com/img.php?image=27885_IMG_0811_122_472lo.JPG

[darron]

looks really cool. why don't you just use one voltage regulator instead of a billion resistors?

[liddokun]

Could you possibly use a micro controller to change it from on and off? With micro controller, you could probably coontrol two of those, have on swtich on/off,
have the other one switch drive/clean.

[andronico]

If you want to have messages in an easy way (dirty / clean, on / off, low / high), you can use an acrylic window with a text in reverse colours masking the windows.  Like a power on indicator but with a text...

[birt]

i think you could have just paralled all the leds you needed for the word "on" and used only one current limiter and the same for "off" instead of using all those resistors. correct me if i'm wrong here.

oh and i'm definatly stealing your idea. sorry :p

You know that thought crossed my mind but for some reason I didn't breadboard it just to see if it would work that way. I just went for the gusto, haha.

Haha, steal away. Just gimme a little credit for it now and then. 

you were right not to do that i think, the more i think about it the more i think it wouldn't work
right now when you have the word ON there are still parts of OFF visible because they get power through 3 resistors in series. the first is the resistor of the first part (which is used in both words) the second is the resistor used for that same part when OFF is lit and the third is the resistor of any unused part of the other word. so the more parts both words have in common, the more unused parts will still light up a bit...

if you use only 2 resistors every part of both words will light up.


edit: unless you use some diodes to block power from going to the wrong parts of the display...

wires from both circuits going to the same led segment have a diode in series right before they join at the segment.

in your setup you wouldn't have 25 resistors but 2 resistors and 18 diodes. not really a big advantage in pcb space and cost but there will be no "ghosting" as you call it without a big fancy switching setup

edit 2: i just noticed it's even simpler. you hard wire all segments that are used in both words and only feed the other segments from the switch. then you need 3 circuits with one resistor each.

can someone please correct me if i make a mistake here

[ugly_guitar_guy]

looks really cool. why don't you just use one voltage regulator instead of a billion resistors?

Unfortunately, I'm still a relative newb to electronics so this way way the easiest way for me to understand it initially. If someone wants to offer some info on how a voltage regulator would work in this situation that would be cool.

you were right not to do that i think, the more i think about it the more i think it wouldn't work
right now when you have the word ON there are still parts of OFF visible because they get power through 3 resistors in series. the first is the resistor of the first part (which is used in both words) the second is the resistor used for that same part when OFF is lit and the third is the resistor of any unused part of the other word. so the more parts both words have in common, the more unused parts will still light up a bit...

if you use only 2 resistors every part of both words will light up.


edit: unless you use some diodes to block power from going to the wrong parts of the display...

wires from both circuits going to the same led segment have a diode in series right before they join at the segment.

in your setup you wouldn't have 25 resistors but 2 resistors and 18 diodes. not really a big advantage in pcb space and cost but there will be no "ghosting" as you call it without a big fancy switching setup

edit 2: i just noticed it's even simpler. you hard wire all segments that are used in both words and only feed the other segments from the switch. then you need 3 circuits with one resistor each.

can someone please correct me if i make a mistake here

Hmm, I shoulda thought of the diode. That will probably be the easiest fix in the meantime since I have it already set up. I'll give that a shot this weekend.

As for your second idea, I'm not sure I follow. Can you illustrate the idea?

[frequencycentral]

edit 2: i just noticed it's even simpler. you hard wire all segments that are used in both words and only feed the other segments from the switch. then you need 3 circuits with one resistor each.

can someone please correct me if i make a mistake here

As for your second idea, I'm not sure I follow. Can you illustrate the idea?

Yeah, this IS the way to do it - permanently power the segments common to both words via one resitor, wire the word specific segments to either side of a 3pdt using two more resistors.

So simple it hurts.

I'm defo gonna do this. Credit to Ugly for the initial idea and Birt for refining it.