[LukeZ]

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.

[LukeZ]

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.

[Lotuswins]

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

[LukeZ]

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.

[LukeZ]

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.

[pandknz]

Hi all

I have just placed an order with Digi-Key for the components, with a bit of their help I have added some alternative parts and these are all available.
If you see something wrong please let me know

Cheers

[LukeZ]

The BOM looks fine to me.

[LukeZ]

Hello Luke,

I am finally going to test the TCB, Scout and OP Sound together.

Just a quick question on the serial link wiring.

Looking at the schematics I was going to wire basically pin to pin, as follows:-

TCB Pin 2 (Tx) to Scout/OP Sound Pin 2 (Rx)

TCB Pin 3 (Rx) to Scout/OP Sound Pin 3 (Tx)

I assume Pin 1 (GND) is not required if all powered from the same battery.

Is there any chance of continued firmware support for R10 of the Scout?

Best Regards

Neil

That's correct, except because the sound card has two connectors, the typical approach would be to connect the TCB to one of the connectors on the sound card, then use the second connector on the sound card to go to the Scout. In this case the connection to the sound card is just as you've described:
TCB TX -> Sound Card RX-I
TCB RX -> Sound Card TX-O

Then from the Sound Card to Scout:
Sound Card RX-I -> Scout RX-I
Sound Card TX-O -> Scout TX-O

That second connection is slightly confusing due to the nomenclature on the board, but just treat the Sound Card as a straight pass-through of the TCB signal.

You are also correct that if all three boards share a common ground, then the GND pin of the serial connector is not required, but it would not be a bad idea to include it anyway.

As for R10 of the Scout - I am not planning to continue firmware development for it, however as of right now it possesses all the same features as R11 firmware. In other words, R11 does nothing that R10 doesn't, it just uses different chips.

[Ncartmell]

Hello Luke,

Mixed results on testing the Scout, I will test Op Sound later.

All firmware appeared to load correctly.

After playing with TCB for a while I got forward movement and left forward turns on M1.

Scout has solid Blue LED so serial connection appears Ok.

No other motor control was available (M2 nothing, no reverse and No right turns).

Could you email a .opz file for just basic control with no triggers/events so that I can eliminate my inexperience with setup.

I am also suspecting my Radio, Graupner MX12 with a Corona RP6D1 (I modified for serial PPM O/P). However Red/Green LED's seem to show correct motor control on the TCB.

Neil

[LukeZ]

Almost certainly the issue is a short on the motor driver chip M2 during reflow. This is not hard to do, and I have done it myself on occasion.

The fact you are getting correct lights, and correct functioning of M1, tells me the firmware and your radio setup is working as it should. There is nothing different from the software's point of view, of controlling motor 1 versus motor 2. If you had an issue with your radio or your receiver, you would also not be able to get motor 1 working at all. The fact that so much works, but one thing does not, tells me the problem is almost certainly a physical issue with your Scout.

Because the motor driver chips have large pads on their underside, it is very easy for them to short if you put too much solder paste on them before reflow. You can check the visible pins of the M2 chip for shorts, and if you see a short you can try to correct it with a soldering iron. But more than likely the short is on the underside where you can not see it and can not fix it. You really almost can't have too little solder paste when assembling these. The thinnest layer possible is what you want, anything more can cause problems.

There's no need to send you a "basic" opz. You can reset all values to default yourself within OP Config (look in the Tools menu). And you can easily delete the four standard triggers that come with the default settings (select each one on the Functions tab then click "Remove Selected Row"). But really the most important thing is that you have radio setup completed correctly, but it sounds like you do.

I'm afraid you're looking at building another Scout. Unfortunately without special equipment you are not likely to get the motor chip off and replaced, without destroying the rest of the board.

[Ncartmell]

Hello Luke,

I looked at the board today with a magnifier and I could see a tiny amount of solder that has squeezed from under M2, so I think your assessment is spot on.

I am glad this has happened with my first build as I will now  use the mask for applying solder paste to the board but not for under the IC's.

I will attempt to remove the IC's.

At work I have access to a desoldering station to remove the connectors, I will then take advice if the Hot Air Station will be able to remove the IC's.

If this is not possible I will try the hot plate and try to lift off the IC's when the solder melts, nothing to lose as the board is non functional.

Many thanks.

Best Regards

Neil

[LukeZ]

The hot air rework station is probably your best bet, since it should be able to remove the chip without melting too many other components around it. Good luck, and keep us posted.

[Ncartmell]

Hello Luke,

I have completed the build of two more Scout's and I just used a very small amount of paste on the pads under the IC's.

I examined them under a magnifier and I checked for "shorts" prior to powering them up, everything looked good.

Bootloader and firmware loaded ok.

Both however did not work perfectly, both motors ran but not correctly and I am puzzled.

If I number the positions on the throttle/steering joystick as follows to make explanation easier and then say which motor ran.

1 Full Forward left
2 Full Forward
3 Full Forward right
4 Left Neutral
5 Centre
6 Right Neutral
7 Full Reverse left
8 Full Reverse
9 Full Reverse right

Scout 1 (Impedance min 200k, Motor O/P's wrt to Bat +ve)
1 M1
2 M1 & M2
3 M2
4 M1
5 None
6 M2
7 M1
8 M2
9 M2

Scout 2 (Impedance min 200k)
1 M1
2 M1
3 None
4 M1
5 None
6 None
7 None
8 M2
9 M2

Scout 3 (first build, I have done continuity check and lowest impedance was 200k)
1 M1
2 M1
3 None
4 M1
5 None
6 None
7 M1
8 None
9 None

Since both motors ran for TCB's 1 & 2, the Motor IC's should be ok, could there be a component failure, wrong value, dry joint or ?
Any suggestions?

Can you monitor the serial stream to see if the correct information is being sent by the TCB.

Currently I do not have a gnd connected for the serial lead but I have a Blue led.

Regards

Neil

[LukeZ]

The Scout can be connected to OP Config in Snoop mode, but I can't remember how much information it gives out. I think at this point however we are safe in assuming the firmware is operating correctly, and we need to look elsewhere for the problem.

The first thing I would do is connect the ground on the serial connection. Your results appear to be somewhat random and this could indicate a poor communication link.

Secondly, what version of the Scout board have you built and which ICs are you using? Hopefully not, but it could be possible you have put the wrong IC on the wrong board.

Also, note that it is possible to short a motor IC such that it will work in one direction but not the other. Excessive heat on the motor IC is also a good signal that something is wrong. This may be the case on your Scout 2.

Third, you can eliminate the TCB and serial communication entirely by running the Scout in RC mode. A servo tester is convenient for this purpose but you can also just hook it up to a standard RC receiver. This is a simple and straightforward way of testing the hardware. If the motors don't move in forward and reverse with a basic RC signal, the likelihood is that you have a short or some other physical problem.

Your Scout 1 seems to have the most functionality. I almost wonder if maybe you have an issue with Radio Setup, possibly inadvertent trims set on your transmitter, or the like. Run it in plain RC first to verify the motors are working, and if so, re-do radio setup and try it again with the TCB (with ground connected on the serial port).

[Ncartmell]

Hello Luke,

I couldn't find my servo tester so I have ordered another, put it away safely 😂.

Whilst browsing for some more VNH2SP30 motor IC's I noticed you can buy them pre made for use as single motor boards or as a twin Arduino shield.

So I bought two singles, the shield, a micro Nano and an R3 UNO.

On Intstructables website they have a tutorial on the Nano and Shield setup with code.

So I thought if I modified your code to run on this it would be an "alternative" Scout.

Although no temp monitoring/ fan control, I will add volt sense.

However on Github I cannot see the code for the R10 scout, could you let me have a copy?

Also I will modify the "Instructables" code to run on the Scout, as you can then control it using the USB from your computer.

I have never used these "Arduino" things before also the last time I wrote code was in the late 70's and it was Fortran77, so this will be a good learning exercise.

If it all works ok I will post the build with results.

Best Regards

Neil