Insanely Bright Phone in Use Light!




Introduction: Insanely Bright Phone in Use Light!

About: depotdevoid is short for The Depot Devoid of Thought, the place where you go when you lo...

I imagine a lot of you out there in instructables land work in an office, or at the very least you know the pain of being on the phone when someone tries to talk to you.  I sit behind a partition, so people often just start talking in my direction, unaware that I'm already on the phone . . . or at least, they used to.

We all have those Plantronics headset/phone lifter combinations half the known world uses these days, so it can be difficult to tell whether or not I'm on the phone at times, even when I am visible.  I asked for an online/in use/indicator light, and what they came up with was a paltry little affair, red lights in a purple case that only has about 100 degrees of visibility and wasn't bright enough to catch your attention half the time.

I wasn't going to stand for it!  If that was the best Plantronics could do, I'd darn well show them one better!

In my shop, I came up with a variety of alternatives and hacks (including this one) to the basic indicator light.  Here I will share with you my final design, as well as some of the abortive attempts and mistakes I made along the way.  Hopefully you will build your own version and share it with us.  In fact, if you do, post some pictures and I'll send you a digital patch, as well as a 3 month pro membership!

Unlike my Plantronics hack, these indicator lights will work for you whether you have a headset or not, as long as the receiver  comes off the cradle when you answer it.

Here's a quick video about it, full instructions are in the following steps:

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Step 1: Be Prepared to Make Mistakes!

As a someone who's big into DIY, I am well aware that things may go wrong when I'm making a project.  I have had to scrap entire projects and go back to the very beginning, or fundamentally change the final product when the images in my brain collide with reality.  I have never had so many setbacks with a project as I did with this one.

The very first problem I had was power.  I thought I'd just be able to power the thing off of the same plug the old light fit.  I measured the various voltages, dummied up a prototype and plugged it in--and suddenly the lifter wouldn't lift.  I'm still not sure what I was doing wrong, I guess I was probably just drawing too much power from the system or something.  In the end, I had no choice but to go with a separate power supply.

My original idea for this project was to take the basic concept of the bike lights I built for my daughter way back in my very first instructable and apply it to the in use light for my phone.  In fact, I did just that for a coworker before I built my own, I made three strings of blue LEDs and wired them up to a driver board I'd harvested from a toy.  I put the whole shebang in a clear plastic tube about four feet long and he taped it to the edge of his desk. 

During this process I hit my next snag.  There are a lot of little toys out there that blink and flash for a short time when you bump, bounce, or squeeze them, and the electronics are all very similar.  In order for one of these to work for this project, it has to have three things going for it:  at least 3 spots for LEDs, the ability to drive multiple LEDs in parallel from each spot, and it has to keep flashing when the switch is held down.  I had a shockingly difficult time finding one!  I tried everything in my junk boxes and bought probably four different toys and at least one bike light before I found something in the dollar aisle at Wal-Mart that actually worked.

After I built the light for my coworker, I started on my own.  At first it was going to be a larger version of his, and with more colors.  I built it just like that, in a larger tube, probably ten feet long!  It was kinda cheesy looking though, it just didn't look so great once installed, though it seemed to work alright.  I was testing it at night though, and the next day I realized that I was trying to drive too many LEDs with the little circuit board I had, and they were too dim, people didn't even  notice when they were on!  After a few days of this, and realizing I was really missing my old lights which I could change to suit my mood, I ended up back in the shop redesigning the whole thing.

Even though I had a ton of problems with this, I stuck to it.  I think the final result is awesome and totally worth all the trouble.  Still, there were times I just wanted to throw the whole thing out and just forget about it!

Step 2: Materials and Tools

Enough preamble already, let's get to work!  To build your very own insanely bright phone in use light and forever be certain everyone will know when you're on the phone, you will require the following bits and pieces:
  • Some sort of IC socket (available at radioshack, online, or in your old and busted electronics)
  • LEDs of various sorts
  • Full line copper clad perfboard (I got mine from Norvac Electronics)
  • A flashy light up toy you don't mind tearing apart (I used a "Star Ball" from the dollar toy aisle of Wal-Mart)
  • Spare wire
  • Some pins and six socket wide connectors and one 2 socket connector (I don't know what these are officially called, so I'm not sure where you buy them--mine were harvested from old electronics or found in electronics grab bags)
  • 4.5-5v DC wall wart
  • Either a normally on momentary contact switch or the spare parts to build one (I used parts cut off a broken kids' keyboard, a spare spring, and some stiff copper wire--this will be covered in detail in step 3)
  • Solder
  • Epoxy (I use E6000)
  • Hot glue
  • Magnets (optional; I needed these to attach the board to the metal part of my divider wall, you may or may not need this)
  • A little bit of thin wood or plastic to insulate your circuit boards from the magnets
In addition, you'll need some tools:
  • Soldering Iron
  • Hot glue gun
  • Rotary tool with cutoff wheels
  • Wire cutter
  • Solder sucker (optional, but nice to have)

Step 3: Build a "Normally On" Momentary Contact Switch

Most contact switches (i.e.: only activated when held down) are normally off, and when pushed down they close a circuit and make a connection.  A normally on switch is already connected, and when you push it down you break the connection.  We will use it in this project so that when the phone receiver is down, it pushes the switch off and breaks contact between the power supply an the LED board.  When the phone is off it, the switch goes back to it's normal position, contact is made, and power flows to the driver board.

You could probably buy these on the internet, but I scoured Norvac and Radio Shack looking for one and came up empty handed.  Buying a prefabricated switch would save a lot of time and headache, but I think this purpose built design is pretty awesome.  And I'm pretty pleased with myself for coming up with it.

I harvested a button and some spare plastic from an old, broken keyboard, and a spring from . . . I don't remember, something.  Always remember Malki's rule number 5!.  Cut up the plastic and glue it into the shape of a small box, then put the spring inside.

Next, drill a small hole all the way through the button, and slide in a small length of copper wire.  Place the button on top of the spring.  On either side of the box, place another bit of wire on top of the button wire (see pictures).  The spring pushed the button with its wire up against the wires on either side of the box, making contact between them.  When pressed down the button breaks contact!  If everything seems in working order, glue the top of the box in place, and move on to the next step.

Step 4: Build the LED Boards

The LEDs in this device are pressed into individual sockets so that you can change them out whenever you want a different set up.  The first step in building the LED boards is to make some sockets.

Starting with an IC socket, pull out every third clip.  Once done, you'll be able to cut through the empty spots with a dremel, leaving a pile of little two spot sockets, perfect for an LED.

Next, grab your full line pattern perfboard and start cutting off sections 6 lines wide.  Mark out the rails with these symbols:
  • + = Positive Rail
  • C = Common Positive Rail
  • 1 = First Negative LED Rail
  • 2 = Second Negative LED Rail
  • 3 = Third Negative LED Rail
  • - = Negative Rail
The positive and negative rails are not strictly necessary, so you can leave them out if you want and just make them four lanes wide.  The are just there to run a connection from the DC adapter to the end of the circuit boards.  I put them in so that if I ever decided I wanted to add another device at the end, the connection would be available.

Once everything is marked up, start soldering on the LED sockets.  The circuit board I used has a common positive for all the LEDs, so one leg of each socket goes to the common positive rail, and the other goes to one of the three negative rails, alternating one, two, three, one, two, three, etc.  You'll probably have to solder a little extra wire onto one of the socket legs so they reach all the way to rails two and three.

The final thing to do is to wire a six pin connector to the end of the board, and six pins to the beginning of the next.  Don't put pins on the first board, that's where the LED driver board goes in step six.

Step 5: Add Power

Grab your 4.5 to 5 volt DC wall wart.  Cut off the original connector and attach the two socket wide connector.  On the first LED board, place the two pins your connector will attach two, wired up to the positive and negative rails (make sure to check polarity).

Cut one of the wires to the wall wart and splice in the normally on switch.  I wrapped everything up in electrical tape and shoved it in an old ibuprofen bottle I'd painted black, just to keep it safe.

Step 6: Add the LED Driver Board and Finish Up the Boards

This step is fairly straightforward.  Start by removing the electronics from your light up toy.  Remove the batteries and switch, and desolder the LEDs, but not before marking off which pad is negative.

Solder a wire from the negative battery terminal and the positive battery terminal to the positive and negative power rails of the LED board.  Next, solder a wire from one of the LED's positive pads (remember, they're on a common positive connection) to the common positive rail on the LED board, do the same for each of the negative LED pads, attaching them to the negative LED rails.  Plug in some LEDs and test it out! 

If all is in working order, it's time to finish things up.  My lights are to be attached to the metal top of the divider between me and the rest of the office.  I glued a strip of wood and some magnets to the bottom of each LED board, so I can more them around to whatever position I decide I like.  Finally, pull out the epoxy and hit every connection and weak spot you can think of.  Once done, leave it to cure overnight and bring it to work the next day!

Step 7: Install at Your Desk

Bring your hot glue gun to work the next day.  The normally on switch should be glued to the hang up button on your phone, so that when the receiver is down it breaks the connection.  When the receiver comes up, let there be light!

Place the lights in the most visible place you can think of.  Mine went on the top corner of my divider, which is exactly where people usually look when they want to talk to me.  Put some LEDs in the sockets, and prepare to be noticed!

Step 8: Final Thoughts

I absolutely love this thing!  It is ridiculously bright and I'm sure it absolutely blinds and annoys people.  This is a good thing, since NOBODY is EVER in doubt as to whether or not I'm on the phone now!  No more trying to wave people away while I take notes, or having them interpret my side of a phone conversation as response to what they're saying.  Plus, it's totally awesome and customizable!

Everyone who works in an office should have one of these.  Or ten of these.  I would love to see pictures if you build something along these lines, please post some pictures down below and I'll send you a digital patch and a three month pro membership!

I live for feedback from my readers, so please post your thoughts down below!  Make sure to rate and subscribe as well, I've got plenty more where this came from!

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    8 Discussions


    2 years ago

    Cool idea.

    I'm looking around for something similar, but not an "off cradle" switch. What I need is for the light to come on when the headset is in use. There are $40 ready made solutions out there, but for a 40 cubicle farm that gets pricey. I'm willing to sit down with a soldering iron and make simple lights if there are any hacks for that. Any thoughts?


    Reply 2 years ago

    Unfortunately no, I'm not savvy enough to really get down and dirty with this stuff. We switched over to a new phone system last year and I had to completely reconfigure this one...fortunately I saved an old headset lifter from the previous system and was able to use that as my new in-use switch. Buying one of those new is like $40, and I don't really know how you'd build one from scratch.

    If you come up with a solution I'd love to see it! My current one is a big kuldgy mess of hot glue and electrical tape and it would be nice to replace it with something a little nicer.


    Reply 2 years ago

    My initial idea is to get a gender-bender (little plastic phone line connector part with a female RJ11 jack on each end), bust it open and solder 2 wires to the internal wires and connect it to a bright LED. If the LED proves to be too much of a draw for the headset to work then plan B would be to use an external power supply and use the headset power to trigger the light to turn on/blink. A Schmitt trigger/OP Amp could work (maybe) as the switching mechanism.

    I have a background in low voltage electrical, but that was 20 yrs. ago, and I barely remember what I had for lunch yesterday (pretty sure it was chicken salad).


    Reply 2 years ago

    I would really hate to waste a mini Arduino on each instance of this device I build.


    8 years ago on Introduction

    And this went over better than the last hack with your boss?


    Reply 8 years ago on Introduction

    Again, all I got was the raised eyebrow . . . he hasn't canned me yet, at least!


    Reply 8 years ago on Introduction

    That is precisely the desired response. Thanks Matt, and vote for me!