ph2t

[ph2t]

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6volt? Are those little watch batteries 6v? wow. never looked at them that close.

No, they are actually 3V. The circuit design I’ve ripped from a site, http://www.talkingelectronics.com . My design will run off 5V using a DCDC convertor that will take the 1.2V from the car’s battery and boost it to 5V. Cool! I’m using CMOS components that run very efficiently of low voltages…

ph2t.

Edited by – ph2t on 08 July 2003 15:27:33

[ph2t]

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ph2t. If you can you alter that curcuit slightly, so that the light run stops at the end, until a button is pressed, then you have yourself a set of racing Xmas tree starter lights. I see you have a 500k resister to control speed, yeah?

I started making one, and the curcuit diagram looks amost the same as yours above, but I fried something, and never went back to it. if you manage to make one, post the diagram here. I’m sure a few people would like to scale starters lights for their race tracks.

That’s a great idea Dave. When I get some time and if the interest is there I’ll make one. I would do a bank of LED’s that change, red, yellow, green, etc…. With a little piezo speaker for the start horn….

ph2t.

[ph2t]

Lock in 4 eddie……:p

[ph2t]

Kero, get some TOMY pullbacks dude. I’ve just put an order in to toyeast and I’m getting me some of those babys. The tyre/rims are mad on ’em……Along with some 4.0/4.2 and 200maH beasts……

ph2t.

[ph2t]

True that G, but I’m gonna use SMD parts for the 555 timer and 4017 cmos counter, that will keep it small. Also the diodes (IN4148) aren’t needed, the proto works well without them so I’ve turfed those components…..

[ph2t]

Look for the “New Dual Cell” thread under Bit Science at tinyrc.com for more info about DCDC converters.

ph2t.

[ph2t]

Very nice! You’ll have to get some video done of the track in action!

ph2t.

[ph2t]

Thanks dude, I’ll give it a whirl tongiht.

The reason why I ask is that I’ve managed to rip out the old 3V DCDC converter and replace with a 5V one. My goal is to increase the RX power and get a greater range. When I do this the RX is actually worse off. I get spasmodic reception at best. I gotta re-tune the inductor and test to confirm if the 5V boost to the RX stage is a feasible one.

ph2t.

[ph2t]

Thanks for the info M.

ph2t.

[ph2t]

From where the “crip cap” is located on the RX pcb I beleive it is in parallel with the 100uF cap on the output stage of the 3V DCDC converter. Like what GT said is is prolly there to get rid of high freq interference.

From what I’ve read about DCDC converters usually a high value cap (in this case the 100uF eltrolytic cap, tha big black canister thingy :D) is use to filter any ripple on the output. The “crip cap” wouldn’t help this principle so it’s prolly there to counter RF interference.

Also, I’m having a bugger of a time in turning the ferrite core of the tuning inductor on the PCB. I melt the wax and then suck it up using solder sucker, but the pr1ck of a thing still won’t turn very easlily. I’m using a wooden “paddle-pop stick” cut and shapped to the ferrite core to be able to turn it but without much luck. Any suggestions fellas? Maybe melting the wax first isn’t a good thing ’cause it’s prolly melting futher into the thread and causing the ferrite core to stick, arggghhhh!:evil:

ph2t.

[ph2t]

M, what surface are you using for the track? Do you then paint this surface? If so how does it affect the cars handling?

Thanks mate,

ph2t.

Edited by – ph2t on 06 July 2003 19:58:47

[ph2t]

I gotta fix mine up as well, been way to slack lately…..

[ph2t]

Is use spray cans. The cheaper and nastier the better! lol! Getting into decals now though, they’re pretty darn cool as well.

[ph2t]

To quote The Castle.

“Get your hand off it Daryl….”

ph2t.

[ph2t]

yeah otp, spill……

ph2t.

[ph2t]

post the pictures in the members gallery.

ph2t.

[ph2t]

Hey Trackydacks, put the car in a blender and see what happens……:approve: You will prolly get more enjoyment out of it that way! lol!:p

ph2t.

[ph2t]

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Just had a look at the bitpimps site, i think ill give this one a miss, their cars are incredible.

They are judging on more than just cosmetics, us techo’s will have our day….

Edited by – ph2t on 25 June 2003 15:49:07

[ph2t]

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uA’s,

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The NiMHs in BCGs dont fully discharge

does the radio gear continue to drain the battery? or is that where 0.7Volts comes from,radio gear only works when .7V or greater is there?

Perriscope, the DCDC converter on the RX pcb cuts out at this voltage and therefore doesn’t supply any current to RX circuitry or the RX2 chip. The rest of the circuit (steering and h-bridge) runs off the 1.2V batt source and this won’t be drawing any current because the RX2 chip is not on to be able to turn the transistors (in h-bridge and steering) on either.

As a note, the car draws approx 6-8mA whilst idle from the batts until it hits this dropoff point.

ph2t.

[ph2t]

Thanks M, muchos gracias!

[ph2t]

Yeah, I’m getting of my arse and going to enter this comp as well.. The prizes are mad!

[ph2t]

I have floorboards at home and the more sticky the rear and front tyres are the better the handling. I’ve noticed that having med -> hard tyres on the front just causes a lot of over steer….

[ph2t]

It’s possesed!
😯

[ph2t]

How are we doing the orders M-Coupe? You gonna handle these or share us your email contact? (read: please please please please…..)

:approve:

ph2t.

[ph2t]

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Is it just my computer, or has the wheelie vid (above) sped up in the last couple of hours/days?
:)uA

It’s those beers you’ve been drinking……:p

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