Those Little Things That Bug You.

[Zad]

As it is the weekend, I thought I would have some time off "proper" electronics and have a play around designing the enclosure and panels for my project. I used to be hardware manager in a computer games company here in the UK, and learned a huge amount off the artists and graphics designers there, so I always love to play around with stuff like Photoshop and 3D Studio. Anyway, there is something that is bugging me. Something stupidly simple, but which I just can't get "right". The point that's bugging me is this:

Which side should the power light go on?



Almost all my hi-fi gear has power indicators on the left, and I want to put it there (yes, it's not a piece of hi-fi gear, I know). It just seems to look wrong for some reason! Here is a render I did with a space for the 'status' LED just to the right of the model number, which looks okay, but I don't want it there! Looking at it now though, it might be better shuffling up the connectors, putting the model number along the bottom and the name to the right after all. AAARGH! I should stick to being an engineer, its easier than having to make aesthetic decisions!

*Scratches head*

You know what will happen don't you? I will totally forget about it and end up mounting the sockets on a blank panel with Dymo tape stuck on it. Nil desperandum, back to the CAD progs

[DJPhil]

You could pull a King Solomon and put it top center on the faceplate!

Perhaps a bright blue LED that shines down from the bottom and lights under the case?

Ah, how bout replacing the plastic frame around the faceplate with an acrylic cutout and use a diffused LED to light it all up in a big ring?

Whenever I'm stuck like this I take out the crazy idea hammer and pound the fine details into finer powder out of spite.

[EEVblog]

I feel your design pain.

Considering that you have symmetry in the connectors, I'd say LED smack in the centre.
I like symmetry 

Big jumbo 10mm LED maybe? Blue? Make sure it's not too bright!

Or make the logo transparent somehow and have the logo light up blue!

Dave.

[RayJones]

Yeah I also looked at the image and the most obvious place was centre top due to the symmetry of the BNCs.

[Zero999]

Another point people have raised is the colour: blue seems to be popular but I don't like it for an on indicator which should be red, orange or bright green in my opinion, unless it's an air conditioning unit, a fridge or a freezer. Blue LEDs have their place but I think they're overused nowadays, a prime example was a vending machine where I worked which had blue LEDS next to all the drinks, when it should've been red for the hot drinks and only blue for the cold drinks.

Funnily enough blue used to be my favourite colour when I was about 10, now it's just whatever colour is fit for the purpose: make the power indicator pink if it's on a  Barbie style radio aimed at girls, green if it's Ninja Turtle style for boys.

In this case would recommend a red LED for your project and possibly another LED to indicate the presence of RF on the input but it should be a different colour, possibly green or maybe green for power, red for RF, whatever looks best. I think an oversized 10m would look tacky, perhaps a square LED shining though a black sticker with white or transparent text saying "ON", "POWER", RF or whatever.

[RayJones]

One the neatest LEDs that I have seen were only 2mm in diameter where they fitted through the panel. Basically looked like a 3mm led that was squared on top and machined down to to 2mm, leaving the 3mm portion near the inner workings.

So you end up with a subtle small indicator of the front panel. Looks classy especially on sleek audio gear.

[mikeselectricstuff]

Given that BNC layout, I'd put it between the leftmost and next-leftmost sockets. Like schematics, power and signals entering on the left  is a general convention.

Or put the power LED leftmost and move the BNCs over, although for ergonomics you want the max spacing between BNCs to get fingers in.

I probably wouldn't label it unless there is another LED. This will help with visual symmetry - as others  have mentioned, a flat-top 2mm LED (or light pipe) flush with the panel looks nice and subtle.

Can you think of a use for another LED for the other side to add some symmetry..?

Also, I'd put the In socket on the left and Out on the right - was there a reason for the way you'd done it? - I know sometimes something as simple as a chip pinout can dictate a panel layout, but you could always out the PCB upside down in the enclosure..!
 
 

[Bored@Work]

Can you find BNC sockets that can be backlit?

[gonnafail]

My vote would be to move the logo to the right side and then place the model number below the logo right justified. Then you can move your power LED to the left like you want.

[Mechatrommer]

a picture worth a thousand words. in my case its worth 4K! putting LED on the side other than the connectors panel will increase cost or assembly time, ask me why? i dont know, just from experience disassembling and reassembling things.

[Mechatrommer]

One the neatest LEDs that I have seen were only 2mm in diameter where they fitted through the panel. Basically looked like a 3mm led that was squared on top and machined down to to 2mm, leaving the 3mm portion near the inner workings.

So you end up with a subtle small indicator of the front panel. Looks classy especially on sleek audio gear.

we can put the actual LED inside the casing, on the PCB perharps, and use specialized shaped transparent glass/plastic to maneuver the light out of the box, down know what its called, but i've seen it used in quite a number of products including my late cheapo Canon printer (dissambled and decommisioned). so we can make of the glass/plastic to any shape/size we want on the outside/visible side of the box.

[Jon Chandler]

The light pipe is a good idea with the LED on the PCB.  Or use a right angle LED on the board.

I'm with you.  Too many blue LEDs.  Make sure it's a diffused LED.  I hate the ones that light up the room like a beam from a lighthouse and leave spots in your eyes!

[Zad]

Excellent response guys! I can't replace the bezel unfortunately, it is (for now) a 1-off project with a standard £21 Hammond 1455T2201BK enclosure and a new bezel might cost a bit more than that.

I hate stupidly bright blue LEDs with a passion too. I have an Altera FPGA eval board with 5 of the buggers on the underside. It looks 'cool and sexy' when its sat on the desk, but if you pick it up and turn it over to press reset, use the power button, or do anything useful really, the blue LEDs blind you and leave you with yellow blobs in front of your eyes. In my project, it is a status LED rather than power only, so my intention is to make it an RGB one, using various colours to denote power on / self test passed (green) failed (red) active (blue) etc. I hadn't thought about fitting it in the centre!

I had intended to mount the LED on a PCB behind the faceplate (secured by being soldered to the BNC sockets) with a small diameter hole drilled through, but I really like the idea of a light pipe. Acrylic fibre optic is cheap enough and I can probably attach it to a through-hole LED with heat shrink sleeving. I was pondering extra activity indicators just to the top left of the 1st/2nd/5th sockets too, so using a light pipe will give me the flexibility to mount the LEDs anywhere on the control PCB and worry about the front panel layout later. If I had a machine shop, I would love to CNC mill an acrylic sheet to mount at the rear of the panel to illuminate around the sockets etc, but sadly I just have a drill and a Dremel-alike, and my skills aren't quite that good (yet!).

The reason the Out socket is on the left is because the logical flow is left to right. The unit generates a signal (RF Out), which is fed to an external reflection bridge. In turn, the bridge it sends signals back to Forward and Reflected. If it is a 2-port device (for example a filter) then it plugs into to the 'Through' connector. RF In is used for a secondary function (spectrum analysis).

Superb ideas there

[Zero999]

I hate stupidly bright blue LEDs with a passion too. I have an Altera FPGA eval board with 5 of the buggers on the underside. It looks 'cool and sexy' when its sat on the desk, but if you pick it up and turn it over to press reset, use the power button, or do anything useful really, the blue LEDs blind you and leave you with yellow blobs in front of your eyes.

Have you thought about increasing the series resistors or changing the LEDs to a more acceptable colour?

In my project, it is a status LED rather than power only, so my intention is to make it an RGB one, using various colours to denote power on / self test passed (green) failed (red) active (blue) etc. I hadn't thought about fitting it in the centre!

How important is the information given to the user by the different colours?

Is it just for you or will others be using it?

If it's important and others will be using it, it might be a good idea to use separate LEDs in case they're colour blind, although you're pretty safe with red, green and blue, avoid relying on them being able to differentiate between red and yellow or yellow and green as red/green colour blindness is quite common.

[Kiriakos-GR]

I have to propose an other different approach .

No LED at all ....  just an self illuminating mini switch at the rear panel .
Yes the classic red ones , mini version.
   

[JohnS_AZ]

Somewhat off topic rant...

Blue 7-segment displays should be outlawed.
As a person ages and their eyesight gets weaker, it is -MUCH- harder to focus on blue things than it is red things.

As for Zads project, I also vote for multiple LEDs. The color blind issue is valid, but bottom line, more blinky lights is always a good thing.

[Zad]

Very valid points. In the first instance, it is for me only. For all that I am a self employed EE, most of the work I do is commercially sensitive, so I am tied up in a non-disclosure agreement. Unfortunately, this means that I have very little in the way of a 'portfolio' to show prospective clients - and as Dave says, there's nothing quite like taking something along to show them what you can do. This project, although a 1-off and useful to me, will be used to show my RF / power / CAD / embedded / app software design skills. At this stage, I have no intention of making them available commercially. But as it could well be useful to the amateur radio community, I will to some extent be making it open source.

The status indicator is mainly to give a go/no go indication while I am developing it, but we have seen with the Fluke 87V that even the best designed product can brick itself, so it would be useful to have an indication of problems such as checksum failure / watchdog timer overflow. The red fault indication will flash (possibly an error code) so actually being red is just an additional warning. Changing colour when actively analysing is mainly for effect, as the main user interface is via PC software. I did consider using a small LCD or OLED panel for status text, but I don't think that would add anything, merely add complexity, time and cost.

With regard to the Altera FPGA dev kit, if I were going to use it for an extended period of time, then I would increase the LED resistor values. Unfortunately, Altera have packed so much stuff onto it and made their software so complex and tied up in licensing restrictions that it is phenomenally hard to use. It is on my pile of "things to do when I have a spare week".

Mike

[Mechatrommer]

Zad. what software do you use to produce the rendered product picture? specially software to build the 3D model for it?
picture: just to share my unprofessional CADding talent

[JohnS_AZ]

Huh. Well given what you said about wanting to use this as a display piece for trying to secure new contracts, I would absolutely add an LCD display. And I'm afraid I'm going to back pedal and suggest using a tiny blue LED as the power indicator.

I've been on many interviews for technical projects where the person, or some of the people in the room were as dense as red bricks. As dumb as this sounds, having an LCD display in the front panel would make the device appear much more technically impressive. While -WE- all know better, to the uninitiated your device might look like nothing more than a passive filter stuck in a cool box.

This will REALLY sound lame ... but I would also make it beep when you turn it on.

It seems to me this is as much a marketing (yourself) exercise as it is a technical one.

[NiHaoMike]

Blue looks good if you diffuse it enough or run it at a sufficiently low power. Also look at blue-green (emerald?) LEDs.

In general, use green and blue LEDs for indicating device power and general status, and save red and yellow for faults and warnings.

[Zad]

Hi Shafri, I use Autodesk 3D Studio Max. The enclosure was imported from the manufacturer's (Hammond) own CAD files. The screw heads and BNC socket are my own models, taken from a product data sheet. Textures are fairly simple ones hacked together in the 3DS editor and Photoshop. Is that a Toon renderer that you used on yours?

The sort of people I talk to aren't usually marketing or upper management people, but engineers or at least engineering managers. So they tend to be more impressed by a nicely laid out PCB or an innovative circuit schematic than they do with flashyness. An LCD or colour OLED would be nice to have, but I'm getting a bit of feature creep already and within reason the sooner it gets built the better. I have I/O pins spare, so I think I will include a header on the control board with standard text module power and I/O lines. That at least leaves the way open to fit a display without re-designing the whole board.

The RF sources are both capable of being modulated very quickly and precisely, and the controller will synthesise standard test tones (there will be enough USB and controller bandwidth to allow for streamed audio from the PC, but that is beyond my USB skills for the moment). To monitor the modulation, I have included a simple audio output on the uC's DAC output, with a LPF and a standard LM386 amp feeding a small speaker. I had intended just to play a sinusoidal beep but, thinking about it, there might be flash space for a few short samples. A bell perhaps, nothing unsubtle like a fanfare. Unless I am pitching at Californians


Mike

[Mechatrommer]

Hi Shafri, I use Autodesk 3D Studio Max. The enclosure was imported from the manufacturer's (Hammond) own CAD files. The screw heads and BNC socket are my own models, taken from a product data sheet. Textures are fairly simple ones hacked together in the 3DS editor and Photoshop. Is that a Toon renderer that you used on yours?

toon renderer? no not sure, i think not, its just a custom photoshop action i've made from info in the net. i used to model 3D object in 3D Studio, but dos version, but now its Windows version and i'm kinda left behind, cannot even do the texturing right, just rendering a "milked" color and surface object in 3DS Max but 3D object made in AutoCAD. final touch up in photoshop, but... as i mentioned, my result is not that professional

[Zad]

I know what you mean about textures, they can be a real pain to get right. Don't be afraid to Google around "borrow" textures that are freely available. To get a good milk texture you need to use sub-surface scattering functions, which are pretty advanced rendering to be honest. Certainly beyond me.  Toon renders give an effect similar to yours, like it was drawn by a graphic artist using lines and flat shading.



http://archondefender.blogspot.com/2008/03/3d-made-easy-4-toon-rendering-in-3d-max_08.html