Yes and no.   All PCBs are finished and ready to run. I still have not begun to program the whole thing - but that should not be the problem.   Unfortunately I have managed to totally, really totally mess up the power supply. This hinders any real advantage. I think I will come back to...

What do you think about the Panasonic ERA series? 10 to 100ppm, 0402 to 1206, and a number of wattages? Of course not as good as the Vishay above - but at least in a reasonable priced range.

I strongly sugest to change your pads to accept 0805 or even 0603 resistors. These are industry standard sizes and it will be much easier to find appropriate resistors. These sizes are still very easy to solder (even though you probably will be anxious because of the size - but I learned...

To keep you updated: The boards are ordered (change some little details). So expect some nice action shots next week or one week later. LCDuino is laying at home, waiting for a task. I need my preamp, missing my music. Case is designed and planned but not ordered yet. So in the next...

You are right. Solder masked vias in small pads DO NOT work. But honestly I think that your are much more experienced her as I am. But just as an conclusion i think: For everything bigger than 0603 vias in pads are fine as long as you solder by hand. For 0603 vias in pads are doable, but...

Quote: Originally Posted by cobaltmute The SparkFun link you had earlier tells you have to do it in Eagle. Now if only I could figure out how to do it in Ultiboard... Yes and no. It works for vias outside of pads. But not inside of pads. Because there you already have 'no...

Quote: Originally Posted by deltaydeltax I've done "via in pad" technology. My most complex board was a board with a BGA containing over 200 balls. Each ball went to a pad which had vias. To keep the solder from filling the holes, I had all of the holes silver filled, then their ends...

Quote: Originally Posted by Fixz8 The "solder stealing" is really only an issue if you're using solder-paste in a production environment. If you're hand-soldering with wire-solder, it doesn't matter at all. The only case when it's annoying hand-soldering is when it's in a tiny pad...

Quote: Originally Posted by peranders My QRV08 design requires really dedicated builders but believe it or not this is number two in popularity and QRV07 is number one, also SMD! QRV08 is my personal master piece and the only headphone amp in the world which has a quadruple super...

Quote: Originally Posted by linuxworks I am. after the learn-sequence is complete, the array of codes is saved in eeprom. I'm using working ram to save temp values and only syncing to eeprom if the user FULLY completes learn-mode. if he bails out in the middle or lets the system...

Quote: Originally Posted by linuxworks code space is about halfway used; but one issue I'm running into is RAM usage! the learning remote eats up a lot of array space since hex key codes are stored in longwords and arrays-of-long could eat up your ram/heap space if you are not careful...

Quote: Originally Posted by linuxworks update: (note, we're almost at the 6000 lines of C code-point. this stuff really adds up but there's a lot of functionality in this system) Is it possible to introduce 'Feature defines' since I can assume that not very much space...

Quote: Originally Posted by glt Hi linuxworks, what is the behaviour if you do more than "touch up"? Suppose I turn on the device and the pot is at min, then I use the remote to increase the volume to say mid-vol. If I start turning the pot, does it not increase the vol until pass the...

Quote: Originally Posted by Ynis Avalach Is there a good source or way to start into arduino programming, I started with a C++ book which I will read now. Because I have no knowledge of programming yet. I know, but it's part of my studies anyway, why don't start there, where their's a...

As prelimnary last board I present the single ended to balanced converter. It is based on the DRV134 chip by TI. The schematic is very simple and more or less directly from the datasheet. Add a relay to circumvent the conversion for balanced signals, add an ATiny13 to control the relays (it...

I do not think it is necessary to use opto isolators. You could use independent digital voltage supplies for the micro and the switching circuit. But I do not see the point in this. Since you will most probably have only on digital supply anyway - else you would need several transformers and I...

No problem if all digital components share the same ground and are driven by 5 volt. Opto isolators are definitvely protecting the inputs. On the other hand - it is a very controlled environment. I will consider this - but dont be astonished if I reject it. Never had problems that called for...

The 3 address pins enable the use of 8 devices on one I2C line. That should be enough before you have to get 'creative'.

Quote: Originally Posted by linuxworks some code restructuring to stop the repeated keys was needed. now it seems to work ok. I think (lol). last commit-message: should compile

Thats cool news. I think you cannot overestimate the effort to do this. I think you will create a major contribution to the arduino world!

Quote: Originally Posted by glt Now that the attenuator is in a different board, it seems the passthrough connectors are the same as the other connectors. Now, how do we bypass the attenuator? (some inputs have built in volume control and others would require the attenuator) Nice...

Quote: Originally Posted by luvdunhill I personally prefer putting the input connectors on the board itself. Yes, it increases cost of the board and limits the connectors that can be used (though you could always wire the connectors), but I think it's a huge convenience. You are...

Quote: Originally Posted by jtostenr Very nice design How difficult would it be to include a switchable input attenuator on the selector board? Shouldn't add very many components or increase size much. The input attenuator is designed as a separate board, since some people will...

Over the weekend I had some time to tinker with the layouts again. The input selector was too big for me, so I change some things:Using Panasonic TQ4Y latching relays – they are smaller than the Omrons and latching (so less power consumption) removing the possibility to externally power the...

As stated above - I have been tempted doing this. Since they are used for test and measurement equipment - so why should the be bad for audio? Do you have any recommendation. Thanks for your ideas. I am really thinking about doing an LDR base attenuator later - after this project. It sounds...