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al000y
- 23rd January 2007, 08:48
hey

im trying to do this
http://www.uoguelph.ca/~antoon/gadgets/servo3.htm
http://www.uoguelph.ca/~antoon/gadgets/servo3.gif

but i faced a problem

i bought all these
IC1 = LM555 Timer R1 = 2K7
R2 = 68K
C2 = 100nF
C3 = 100nF D1 = 1N4148, signal diode

but they dont have this
C1 = 390nF AND P1 = 2K7, potentiometer

the seller told me that they dont sell 390nF AND 2K7, potentiometer

so any one can help me?

malc-c
- 23rd January 2007, 09:50
So you chose to make that one rather than Alaine version ( http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1338&d=1169308729 )

I use RS components here in the UK and they don't list 390nF value. I'm sure for your purpose a 400nf capacitor would suit. Likewise a 5K trim pot could be used, but you may not need to use all the range to get the 1ms - 2ms pulse width.

malc-c
- 23rd January 2007, 10:14
As this forum is really about Pic programming, why not look at using a PIC to do the job for you. Here's some links I found

http://www.dougrice.plus.com/hp/RCservo/rcservo.htm
(includes HEX code and is simple to build)

http://www.rc-cam.com/servotst.htm
(Hex and documents for download)

http://www.electronics-lab.com/projects/motor_light/008/index.html
(Asm and schematics)

From the same site as your original servo pulser have a look at this one
http://www.uoguelph.ca/~antoon/gadgets/servo2.htm
It uses more standard values

As does this version
http://www.uoguelph.ca/~antoon/circ/archive/servo1.htm

Another 555 timer based servo tester
http://www.hobbyengineering.com/appServoTester.html

And another
http://hometown.aol.com/hprinzler/9610-03a.gif

I could go on.. but I have other things I need to do. Just type in NE555 Servo tester into any search engine if you want more

Acetronics2
- 23rd January 2007, 12:19
hey

im trying to do this
http://www.uoguelph.ca/~antoon/gadgets/servo3.htm
http://www.uoguelph.ca/~antoon/gadgets/servo3.gif

but i faced a problem

i bought all these
IC1 = LM555 Timer R1 = 2K7
R2 = 68K
C2 = 100nF
C3 = 100nF D1 = 1N4148, signal diode

but they dont have this
C1 = 390nF AND P1 = 2K7, potentiometer

the seller told me that they dont sell 390nF AND 2K7, potentiometer

so any one can help me?

Aly,

The total value of the cap must be .82µF ... on the drawing you had 3 possibilities INCLUDING 0.47 // 0.33 µF !!! There's enough room on the pcb to place 2 caps ...

If you use a twin 4.7K pot ( the 2 sections wired in // ) that will fit perfectly.

I use for this design an old 1 channel stick fitted with 4k7 pot ... but here, only 90° of rotation was used ...


Malc ... you begin to look like "Jetpr" ... R = R1*R2/( R1+R2 ) and C1//C2 = C1+C2 sounds sthg for you ???

Alain

al000y
- 23rd January 2007, 17:05
hey

first can you give me link for beginner tutorial in electronics

second yestrday i bought all these(in attach pic)

1-68K R
2-100nF
3-330nF (also they have 400nF but they dont have 390nF)
4-NE555P
5-2.7K R
6-IN4148
7-P1 - 2.2K (they dont have 2.7 he said 2.2 is standard)


if i build the project with these it will work fine and generate 1 - 2 ms ~ 50Hz ?
or it will damage my ESC?

tiger_bel
- 23rd January 2007, 20:46
just a simple test with 180f452 on microchip proto board
servo connected to port B.7

a quick test - without any additional hardware
fyi

init:
gosub rstml
loop:
LCDOUT $FE, $80, " test for servo "

if code <100 then code = 100

if code >200 then code = 200

if portB.0 = 0 then ' button right
code = 100
pulsout portB.7, code
high portB.0
else
low portB.0
endif

if portA.4 = 0 then ' button left
code = 200
pulsout portB.7, code
high portB.1
else
low portB.1
endif

high portB.2
pause 25
low portB.2
pause 25
goto loop

rstml:
low PORTB.1
low PORTB.2
low PORTB.3
low PORTB.4
low PORTB.5
low PORTA.0
return

Acetronics2
- 24th January 2007, 08:44
Hi, Al

If you had told us electronics was a new land for you ... I had shown you THAT :

http://www.york-electronics.com/

Still time to be reasonnable ... and do not tell me about the cost !!!

Alain

For others:

You REALLY think our friend could achieve an unprogrammed PIC "kit" ... as a simple 555 is a great problem.

do not joke ... please !!!

malc-c
- 24th January 2007, 08:59
I thought the guy wanted to build something, rather than purchase a commercial product..

Mind you at $20 it would probably be just as cheap !

Acetronics2
- 24th January 2007, 09:15
I thought the guy wanted to build something, rather than purchase a commercial product..

Mind you at $20 it would probably be just as cheap !


I know that, Malc ...

but this device really is a value !!! ( I know "Rocky", it's him, for quite a while and his work is worth every $$ ... )

Be sure this device is far off from your "miracle" bass beat filter ... ( LOL !!! )

and as many things could be done with the 555 ...

better to excercise on a blinking light or a standalone kit than taking risks with other stuff involved.

Alain

malc-c
- 24th January 2007, 12:48
.... your "miracle" bass beat filter ... ( LOL !!! )

Alain

Don't knock it... by the time I've finished playing with these op-amps I'll be the guru on low pass peak detection filters :D :D