Oh…I see what you mean. that 100K resistor doesn’t exist in the Amber BOM or on the board. (The 100K referenced in the imp002 spec sheet).
Easy enough to tie the red LED to ground.
Huh. You’re right, that’s an omission from the Amber schematic! We’ll get that fixed…
I placed a 10K resistor across pins 1 and 4, and am good to go. I did have to wrap the phototransistor in black tape to get blinkup. Even in a darkened room with my fingers around it wasn’t enough. I’m going to flush mount it into the enclosure, so that shouldn’t be an issue when it is finished.
I don’t know how many times I’ve looked at the imp002 spec sheet and the part about autosensing common anode or cathode LED’s didn’t sink in. Stupid brain.
Sorry to dig this up again - I’m about to design a PCB using the amber as a reference. I notice that the photo of the black PCB above left C10 and C11 out, which are on the PCB but not the schematic (as seen currently at http://electricimp.com/docs/hardware/resources/reference-designs/amber/). I presume they’re not really crucial?
Cheers
C10, C11, and C5 aren’t in the BOM, and I didn’t mount them in my boards. The reference schematic doesn’t show the additional resistor that you need with the LED’s, and even though a 100K is shown in the spec sheet, I believe that a 10K is the current recommendation. Tom recommended this top fire LED, it is a pretty small package. http://www.mouser.com/ProductDetail/Lite-On/LTST-C195KGJRKT/?qs=ohURClPaJWCkP7ius%2bRMYA==
What are you using to design the board? I’d be interested in hearing about what you are doing if you want to share.
I don’t know why none of the hardware shops aren’t making something like the Amber, it is really cool to have all 12 pins, and the extra power of the LDO. I had 10 boards made, sold 4, am using 5, and have one left to build.
Cool, thanks for the info. I’m using Eagle at the moment. Still getting to grips with it a bit, but I’ve created a few bits and bobs with it and had the created by OSHPark.
I’ve got two current projects, both of which are very similar - using an Imp to control relays.
One is for a brew fridge - in short, during fermentation beer needs to be kept at a constant temp. Stick the fermentation vessel in a dedicated fridge with the thermostat removed, along with a low power heating tube. Temp sensors monitor and decide whether to turn on the fridge or the heater element.
Second is for my hot water / central heating system, using relays to switch on CH/HW as and when required.
They share many components, so I’m going to product one board which fits both purposes. My current attempt at the central heating project uses the Sparkfun Imp breakout, an ebay relay unit, and a couple of PCBs I designed, one for the power and one for the other few components.
I want to bring everything onto one PCB, using the Amber design for placement of the vreg LEDs, etc. Much easier than designing from scratch!
Cool. I built a fermentation chamber a few years ago out of a metal storage rack, and 1" foam insulation sheets, and installed a small AC window unit in the bottom to cool it. I could keep the unit down to around 60 just by adjusting the unit temp control. I wasn’t imp at the time, so my lagering fridge just used one of those manual PID controls. If I had been imping…there would have been imps all over my brew stuff. Have you seen the beerbug? One of the forum members, ParasitX is developing it, and it goes inside your fermentor, and can handle blow off. If I ever fire my brew stuff back up, I’ll be buying a stainless conical, and probably ditch all the glass carboys.
I started an Eagle library that I have on github, there are a few things in it that might save you some time. If you feel like contributing, or make a library yourself that you want to share, let me know. Building components isn’t one of my favorite things to do. 
I’ve got a relay board partially built as well, there are a zillion uses for it.
Yeah, I saw the beerbug back before I’d heard of the Imp. It looked really interesting, and I naturally started thinking about how I could make a DIY version 
It’s the straingauge (or whatever it is) that I was struggling with, so never looked any further into it.
I’ll take a look at your github stuff. Much more useful than plain old reference gerbers!
Not sure how I missed this thread before - @jwehr great work!
Thanks. The Amber board is really great. I’d like to see if it could be squeezed down a bit in size, but being able to put the blink up stuff anywhere you like is really nice. I need to get a few more made.
@jwehr We actually do have a smaller version of Amber that we use for some of our internal hacks. It’s called Aria and the PCB is only 1.05" by 1.05". I’ve attached pics of one all built up.
We sometimes don’t release designs like this because they aren’t recommended for mass production. In this case, putting a switching power supply under the imp may negatively affect the WiFi. If you want Gerbers let me know and I can post them, though be fore-warned this design doesn’t have the LDO option so you’ll have to solder the very small TPS62172.
Also, while I’m here, on the existing Amber design C10 and C11 are just for our testing. We used Amber to perform the FCC testing so we wanted a place holder in case we needed some RF bypass caps. You can see them in the schematic jammed all the way down in the bottom right.
Oh man! Please post! That rocks! No worries about the LDO, most of the projects I would use that for wouldn’t be super power hungry. That is perfect for wearable electronics projects…and soldering small parts is just an excuse for me to build a reflow oven. Those gerbers will be on their way to SeeedStudio as soon as you post them. Thanks!
Looks like there is still plenty of room back there for a LiPo charging circuit. impWatch here we come.
Oh, for that you’re gonna want our newest module. Won’t be available for a bit, and you need to add your own antenna, but it’s 10% of the size of imp002
Wow … 10% the size … that’s certainly very cool! Something to look forward to in 2014 :). Happy New Year … all the best throughout the upcoming year.
Still breaking out all 12 pins? Very cool indeed.
I had a couple of the amber boards made and have successfully gotten all of the smd devices down using a rework hot air tool. The LDO is working and producing 3.3V and the opto devices appear to be working. I’m now trying to solder down the imp002 module with a hand iron. This is the first time I’ve tried such a thing. I do not seem to be able to get the solder to completely melt - only partly melting and making a mess. Is there secret to this process?
Alright, here are the Aria schematics and gerbers. I didn’t generate a BOM since it’s so few parts and they are all called out on the schematics. I bumped the rev to 2 because the first rev didn’t have silkscreen for the extra 6 pins.
We use Gold Phoenix PCB for almost all of our PCBs here. For $100 you get 100sq-inches of PCB. For a board this small that would yield 90 PCBs so it’s a bit overkill but for larger designs it’s a great option.
@senger sounds like you’re soldering the ground pins and your iron isn’t powerful enough - the planes are pulling all the heat out and making it hard to melt the solder.
You can try pre-heating the board a little (even in a normal oven) so that there’s less work for the iron to do. Generally you’d have a preheater to do this for you.
The non-ground pins should be easy to solder.
@jwehr there are over 20 pins now