*

Offline LukeZ

  • 302
    • View Profile
  • Kansas, USA
Re: Home Build
« Reply #15 on: November 12, 2017, 07:30:07 PM »
For placing components on the board curved tweezers work best in my experience, I've been using a cheap set I got from Harbor Freight but you can probably find even a nicer curved tweezer in the beauty aisle at Walgreens or the like.
NO SUPPORT THROUGH PM - read why
Open Panzer FAQs

*

Offline LukeZ

  • 302
    • View Profile
  • Kansas, USA
Re: Home Build
« Reply #16 on: November 12, 2017, 07:35:34 PM »
I found the board layout finally that shows where to put which part (initially I thought I'd have to trace back from the schematic...yikes!).

For others reading this later, here is the Scout placement guide Jerry mentioned, from this thread.

Placement is the same for Rev 10 and 11.
Scout_v1r10_Placement.jpg
Home Build Scout_v1r10_Placement.jpg
Views: 64
NO SUPPORT THROUGH PM - read why
Open Panzer FAQs

*

Offline Lotuswins

  • 12
    • View Profile
  • Roseburg, oregon
Re: Home Build
« Reply #17 on: November 12, 2017, 09:15:51 PM »
Thank you so much Luke, you are the man!!

So I just ordered the stencil, 3 mils since I thought the thinner, the better.  Plastic, with a frame to ease the pain 8^).    Its getting easier already. 

I'll try out the heat plate tomorrow using my handy dandy Duratrax RC IR temp monitor while waiting for the stencil to arrive.  The paste bottle doesn't say its recommended melting point (the Mechanic Solder Paste from ebay/China I think you recommended), I assume its 200C, right?

Thanks again!!   Jerry

*

Offline LukeZ

  • 302
    • View Profile
  • Kansas, USA
Re: Home Build
« Reply #18 on: November 12, 2017, 09:32:12 PM »
Yes, the 3 mil plastic is what you want. And yes, I try to keep the temperature to 200* C. I think the actual melting point of the paste is something like 183* Celsius but you need to go a little higher than that of course. If you keep it to 200* C you will have a very nice result.

If you go a few degrees over, don't sweat it, it's not the end of the world. But if you hit 210* C you are probably going to see discoloration of the bottom of the board including the silkscreen, and beyond that you risk delaminating the bottom copper and damaging the ICs.

OSH Stencils ship quickly, not like waiting for PCBs to be made. You will probably get the stencil this week.
NO SUPPORT THROUGH PM - read why
Open Panzer FAQs

*

Offline LukeZ

  • 302
    • View Profile
  • Kansas, USA
Re: Home Build
« Reply #19 on: November 12, 2017, 10:28:59 PM »
Another thing you can prepare for while you are waiting, if you haven't already, is the equipment you will need to program the microcontroller on the Scout. I haven't really posted about this because I assume people going through the trouble of assembling an SMD board at home probably already know this stuff, but for everyone's benefit here is a quick primer:

The ATmega chip on the Scout needs firmware, which you can flash to the chip using OP Config (or the Arduino IDE) and a standard FTDI cable (basically a USB-to-serial converter). BUT, before you do that, the chip will need a bootloader installed. Without the bootloader the chip can't even communicate yet over serial so to get the bootloader on requires a special one-time programming using a different device called a "programmer" connected to the ISP port on the Scout (ISP stands for "in-system programmer").

There are lots of compatible programmers but the cheapest that works well is the USBasp (actually Chinese knockoffs of it). These only cost a few bucks. I have used this one but they are sold all over the place including AliExpress, Banggood, eBay, etc... Note that many of them come with a 10 pin plug and you actually need a 6-pin, so be sure to get one with an adapter (such as the one linked) or buy an adapter separately (like this).

You will probably need drivers for the USBasp device, try these.

Ok, now you have your USBasp and your assembled Scout. The USBasp plugs into a standard USB port on your computer. The ribbon cable on the other end you need to connect to the ISP connector on the Scout which is the 6-pin rectangular connector in the corner of the board (shown in the image below). Align the red stripe on the ribbon cable with the little white triangle on the Scout board. You can either solder headers in those holes and just plug in the USBasp connector, or you can leave the board bare (as shown in the photo) and use a pogo-adapter like this one sold by SparkFun (just hold it on the holes in the board and press down tight). Note that you also need to power your Scout with a battery while performing this operation. Now you are connected, open up the Arduino IDE (you don't need to load any kind of sketch). Under the Tools menu:
- Select "Arduino Nano" as the Board
- Select "ATmega328" as the Processor
- Select "USBasp" as the Programmer
- And finally click on "Burn Bootloader"

If all goes well the bootloader will be installed (Arduino will tell you whether it was successful or not). If it works, you can put away your USBasp, you will never need it again.

Now you need to load firmware. This is much easier. You need an FTDI adapter (like this one or this one) or just an FTDI cable (like this one or this one), or any others that are legit "FTDI" cables/adapters (buy these from a reputable source or you will have driver issues). I prefer the adapters but you will need to supply your own USB cable then. The FTDI adapters/cables use the same drivers as the TCB so you probably already have them on your computer but if not you can get them from the Downloads page.

Once you have the FTDI drivers installed the rest is easy. One end plugs into your computer using standard USB, the other 6-pin wide plug connects to the Scout on the header shown in the image below. Note that one side of the FTDI connector will be labelled "Green" and the other end "Black", make sure these are aligned with the words "Green" and "Black" printed on the Scout board. For this operation it is not necessary to power your Scout with a battery, it will get power from the FTDI cable (though it doesn't hurt if a battery is connected). One thing you do need to make sure of is that you disconnect your Scout from the TCB if you had it plugged in there, because that will cause the firmware update to fail. Now just open up OP Config, select the correct COM port for your FTDI cable, go to the Firmware tab, select Scout ESC and "Get Latest Release", once that is downloaded click the Flash button and your Scout will be programmed. If you are really a glutton for punishment you could download the Scout source code from GitHub, open the sketch in Arduino, then program it from there.

Note that all this rigmarole is the same for the TCB if you are building one of those by hand, except there is no point in doing that since we can now purchase them. For the Open Panzer Sound Card none of this is necessary - the Teensy processor used on the Sound Card already comes with a bootloader pre-installed, and furthermore it requires no special Windows drivers. To load/update firmware for the Sound Card just plug it into your computer with a USB cable, then use OP Config to flash the latest firmware, should take five seconds.
scout.jpg
Home Build scout.jpg
Views: 65
NO SUPPORT THROUGH PM - read why
Open Panzer FAQs