damellis / cellphone2hw Goto Github PK

To make it a little easier to solder the button down.

The current one is flakey.

Maybe something like this:
http://www.digikey.com/product-detail/en/NHD-C12832A1Z-FSW-FBW-3V3/NHD-C12832A1Z-FSW-FBW-3V3-ND/2059236

These should align with the insides of the bigger holes mentioned in issues #19 and #21.

That is, based on issue #19.

Once I find one (issue #24).

Allowing partial countersinking even without drilling an extra hole.

It seems like there's sometimes a need for the bigger screw holes in the PCB (for M2) screws: you might not be able to get M0 screws, or you might not be able to make smaller holes when CNC routing the case (with an 1/8" end mill).

My plan is to make the holes in the PCB bigger and then give two options for the holes in the laser cut case: M0 or M2.

So that the GSM module can detect when the SIM card is present (inserted / removed).

This should enable faster startup by allowing the microcontroller to tell if the module is already started, instead of always resetting it (which is slow).

For example, one with legs (like the microphone).

Hi, Sparkfun ( or Lady Ada ? ) has some extra long footprints oin their Eagle libraries for some surface mount components that make them easier to solder by hand.

Here are the components I struggled with (that could be made longer):
Diode D1.
Capacitors of 1000uF.

Others that might not be possible to get bigger but would benefit from longer pads if possible on at least the important connected pins.
Module M10
Mega 1284.
SIM card holder (as the plastic is in the way for one pad if using a big soldering tip)

The following components was very hard to solder, almost impossible with my 50 watt soldering iron, due to the groundplane design with large copper areas and vias. Pre-heating the board usually helps a lot as adviced from a firend, but if it is possible to change the ground plane design it would also help:

Module M10 "power corner"
Charger circuit components.

Fun projects though!

For example, the AT90USB1286-AU. That way, you wouldn't need an FTDI header and could use the Mini-USB connector (or a Micro-USB connector) for charging the battery and re-programming the microcontroller. This would save some space, I think, although the chip is slightly bigger than the ATmega1284. This is a fairly big change, though, so it probably won't happen for a while.

So that they will accommodate screws that come in lengths longer than 1/2 inch.

To allow for more solder on this potentially high-current connection.

The SparkFun FTDI breakout board is slightly wider than the header at the end of the standard FTDI cable, so it doesn't quite fit through the hole in the case.

If there's room, it would be good to have extra holes for VCC and GND. Alternatively, they could go somewhere else on the board (like near the JST connector for the battery).

The mounting hole near the JST connector is too close to the edge of the circuit board. Move it in, aligned with the others.

The hole in the top plywood file needs to be a bit bigger to accommodate the new solder jumper.

The pins are numbered backwards (i.e. 24 to 31 instead of 31 to 24).

Particularly for the 1206 components (capacitors and resistors and LEDs) but also for the 1000 uF capacitors.

These pieces aren't always soldered in exactly the right place, so the tolerance in the holes in the case needs to be looser.

Seeedstudio stocks LiPo batteries than they list as 5mm thick rather than 6mm. It would be nice to use these slightly thinner batteries so they'd fit better in the 6mm wood enclosures.

http://www.seeedstudio.com/depot/lithium-ion-polymer-battery-1a-p-593.html?cPath=1_3

After issues #24 and #25.

So we can indicate on-screen whether or not the battery is charging, rather than just hooking up an LED to the pin.

The JST connectors are hard to use and I worry about breaking them or the battery wires.

The leads / legs on the current one are thin and close together and hidden under the component.

Since the mounting holes moved inwards, there's room to round the PCB corners more.

Removing the solder jumpers. I've been debugging by uploading a serial proxy program to the microcontroller, which seems to work fine.

Probably everything except the screen and the battery (and maybe the exact SIM socket) can be found on Digi-Key.

Not just an arbitrary pattern of dashed lines.

The screw holes got bigger and moved outward a bit in the latest PCB. I updated the plywood files (top and bottom) and the Inkscape files for the veneer, but the hpgl and CDR files for the veneer still have the old holes.

In particular, the 1000 uF capacitors, diode, and LEDs.

In particular, the PB4 pin. This gives us more control over the buzzer and is also needed because newer version of the GSM module don't generate ring tones.