Oops Okay still needto do that.

Don

 

Sarge,

Now I have continuity between Pins 1-5 1-8 8-5. By the drawing should I have continuity between 8-4?

Thanks

Don

 

That isn't making any sense. Of course 8 is going to have continuity to 8 - it's the same pin!

[eta]

Dang, I just realized I did something really stoooopid. Back later.

 

OK, the circuit board layout is correct, and you got the reading you should have from the relay; continuity between 1-5-8 with no power applied to either coil.

I drew the relay with the contact showing 4-8 made instead of 5-8 made; which threw me off.

I have corrected the art for the library model; the top part layout is attached.

Once you get the board etched and drilled, you could glue the layout to the top of the board.

 

Just in case the board copper is a bit thin around the edges, you might add this jumper:

It's to make sure ground is well connected to both sides of the circuit. Right now, the "copper pour" has everything connected, but if you're a bit thin around the edge of the board where the transistor is, you might have a problem.

This just avoids any potential problem.

Better use an insulated jumper wire, as the trace the jumper needs to cross over is connected to MOT-; the trace will be grounded while the motor is running in the forward direction (T.C. starting his turn), but Vcc (+7.2v) when the motor is running in reverse (T.C. returning to forward).

 

Hey Sarge,

Got it etched drilled populated and wired up including the jumper. Motor will start ad go around but the reed switches have no effect at all. I can hear them open and shut as the magent passes byt it does not reverse or stop.

Don

 

Sarge!!!!

It Works!!! I mean it really honest to gosh works! Found the minor problem. It really helps if you solder the switch lead in...oops!! Okay now to get the figure painted, mounted and adjusted. Then into TIGER tank 312!!

Oh Boy...Oh Boy...Oh Boy!!

I'll post a video as soon as I get it all in one sock!

Sarge you are a true whiz!

Don

 

Cool beans, Don!

Glad you found the switch lead problem pretty quickly.

Did you glue the parts layout on the top of the board, and did that help make things go faster this time?

 

Oh yes much faster. If I wanted to slow it down more. Not this figure but another I have in mind what resistor would you suggest?

Best

Don

 

Oh, you're talking about R2, the 220 Ohm resistor that limits motor current?

You could try various values. 270, 330 Ohms, 390 Ohms, 470 Ohms... if you go past around 620 Ohms, it'll probably start getting mighty jerky.

If you're going to do another one of these things, might look at doing the whole deal in a transistorized H-bridge, and add on a PWM circuit so that you can "tweak" the motor speed to your heart's content.

 

Hey Sarge,

Sorry for the delay. Puter took a big nose dive. I was already to go. It was assembled tested and I was getting ready to make the video, and thought better test it one more time. What I failed to see was my pliers across the board. So when I powered it up...well you can guess. My tank commanders head went around before flying off somewhere behind my bookcase.

But I have rebuilt a new board. My TC should be out of the hospital soon. I gave him a head transplant. So soon I will be able to show the world the incredible 1/16 scale moving Tiger Tank Commander.

Don

 

Gee, too bad about the computer and burned-up board.

But, look at it this way - you're getting lots of practice making circuit boards.

Did you try different values of resistors to slow the motor down?

 

I sure did and the 330 is the way to go! Right ow I'm making a case for the new board so I won't goof it up again. You are right! Making these boards is fun.

Don

 

Actually, you could use some insulating tape on the bottom of the board to protect it.
DON'T use "Electrician's Tape" - the glue will soften and fall off after a few months.

Making a case is OK if you can keep stuff from getting inside the case. If some piece of metal gets in there and rattles around, it will wind up shorting out the traces and cause problems. Using RTV silicone at wiring entrance/exit points will help prevent that from happening.

If you are satisfied that it's working properly and don't want to see it again, you could always use potting compound to permanently protect it. The relay isn't going to die with the small load you have; it's rated for 30A. The weakest points are the traces on the board.

 

Hey Sarge,

All is looking good, real good! Waiting on a new hand and binoculars, Then the headphones and throat mike. I received some very nice uniform decals that will make this guy really a show piece.

I was looking at the ELCTROINCIS GOLDMINE and found they have car remotes and recievers. For those that do not have the RX-18 or the ELMod would it be possible to have the board, reciever operated by a 9 volt battery? That way anyone no matter what tank could use it.

Thanks

Don

 

Well, the board can operate from about 7v to 15v.

If you get much lower than that, the relay won't engage. If you go much higher, there will be too much current through the relay coil.

9v "transistor" batteries won't last very long. They would be better off using eight AA cells in a battery holder; the board will be very happy running with that.

 

Thanks Sarge! I just read the spec sheet and the car remote would be a living breathing nightmare. However the ultrasonic TX and RX look promising. It operates on 24Mhz and the tanks operate on 27Mhz. Hopefully not to close. I would hate to push the button and a $1500 dollar tank rolls off a cliff.

Don

 

Hey Sarge,

I found this http://cgi.ebay.com/1CH-Momentary-R...Control_Parts_Accessories?hash=item439b4e25a7

Would this work?

Thanks

DOn

 

Sure.

Connect up the +/-12v to the battery via a fuse. Connect the NO input to the +12v input so it's fused, too. Connect COM to the RX-18 input on the TC driver board.

Alternatively, COM could be connected to the fused +12v input and NO connected to the RX-18 input on the TC driver board but that would leave the NC terminal energized all of the time.

 

The best just got even better! Thanks Sarge now everyone can have a Operating TC. I am going the 8 AA route. This is going to blow some folks minds!

Don