FREE - RC Heli Optical Tachometer DIY

[Hawk_Sport]

ok i am looking at the pics of mikes again...looks like the mem button may be on 10 and 5? can someone clear this up for me pls. before i really get peeved and chuck this... mem button on 5&6, 7&8 or 10&5? i really need someone to chime in here.... i looked at all schematics again and my board is right as to mikes instructions... but to make sure i need someone who knows this crap to email me so i can send my board schematics .....

[falconea45]

I'm sorry to say this S_H but I think you bit off more than you could chew. Its very hard to do electronic fault finding by remote. No one knows what exact parts you have used or how they are wired etc. so many things could be wrong or you could have a faulty PIC , who knows. You need someone locally with electronic background to check out the whole system.
Don't chuck it someone may get you to send it all to them for them to troubleshoot, I'm just a little far away otherwise I would help out

[jared_of_atlanta]

You'll get the squares on the LCD if the PIC isn't programmed--you did program the chip right? You'll also get them if the signal wires from the PIC to the LCD are not connected or not connected correctly. The LCD is just sitting in its "booted" up state waiting for signals. If you have a multimeter you can put your black multimeter lead to ground and put your red multimeter lead to signal pins 1,2,3,10, and/or 11 on the PIC and you should see the voltage fluctuate--that is the signal going high low high low high low etc.

[Hawk_Sport]

yes the pic was programmed for me. if i had a pic programmer i would set it up again, but i dont have one so i am outta luck on that. if i knew how to make one i would, but i dont . i am good at reading schematics and such but not that good. but following mikes instructions and my board layout everything seems right on. except that +5 on 3. so i switched 3 to neg. thats where i get the black boxes just on the top portion of the screen. i am pretty sure if i had all the parts to make one i would send them all to someone that could make it. but i am minus the pcb board...

[jared_of_atlanta]

Your PCB schematic looks right to me. Assuming there are not bad solder joints and everything was put together as your schematic says, it should work. Try the multimeter thing I described. Also a picture of your board and wires and setup would help us troubleshoot.

[Hawk_Sport]

i shall grab a pic of the whole thing tommorow. there are no bad solder joints at all. if its the pic then well i am done. i'll end up trashing it. i cant afford to buy a programmer for 1 use only or even making one out of what i can around the house ... i am great with soldering and stuff but i must see it on paper or a pic to figure it out. besides that i dont have pcb board and the stuff to actually make it with or even the copper crap for the backs... eesh anyways, thanks and will get the pics tommorow of the board and wires and lcd and whatever else i can...

[philo]

hi guys has anyone had any joy putting together a kit for this project??
i have tried to source the infra red detctor here in ireland and its only available as a special order from the US and costs 20 times more for it here than the cost of the part. any help would be appericated

[Hawk_Sport]

sorry guys no pics of mine as my camera just will not focus close enough. the camera i have really sucks. . so thanks all for the help but it just wasnt meant to be that i have one of these units. i'll go out and buy one whenever i can wich will probly be never but i'll try. take care and have fun... in the meantime i think i'll try to work my heli ... still needing a pitch guage and balls for servos and training gear. so ya thats even taking too much time ...

(unless of course someone is willing to either make a pic programmer for me or is willing to take a look at the whole unit if i ship it to them...)

[JKos]

Computer fans with an RPM output usually provide two pulses per revolution. Some are more, but two is the norm. Has anyone used that output instead of the IR sensor? Seems much simpler. A two slot disc would be necessary.

- John

[Hawk_Sport]

Originally Posted by JKos

Computer fans with an RPM output usually provide two pulses per revolution. Some are more, but two is the norm. Has anyone used that output instead of the IR sensor? Seems much simpler. A two slot disc would be necessary.

- John

how do you figure that will work? still needs the ir led and stuff?. i cannot see the comp fan sensor working on this....

[JKos]

> how do you figure that will work?

Simple. The IR sensor gives you a logic level pulse per slot that goes by. The fan RPM sensor gives you two logical level pulses per revolution. Put a two slot disk on the fan and you then have one pulse per slot.

I've already used this method for my own tach design and it works great. Actually, I used a one slot disk and the code simply handled the two pulses per revolution correctly. Have not tried it with this design.

- John

[Hawk_Sport]

looking at the comp fan actually have it apart now... i see where the sensor is . this reads the rpm off the magnet ? how would this work? having a hard time picturing the disc on it as well. got any pics? i would love to see this ...

[jared_of_atlanta]

I hate to break it to you hawk_sport but the problem you are having isn't with the LED and sensor so an rpm from magnets wouldn't help.

[Hawk_Sport]

the led works yes but still my screen shows black squares... so this is meaning what? that i must reprogram the pic? i am unable to do that as i am on a fixed budget and cant make one either as i dont have the ingrediants to make one. i was lucky by chance a buddy of mine was able to make me this board and just gave it too me. i think maybe that when he mailed it to me that when scanned at canadapost the pic must have got nailed with the scanner as i have heard horror stories of this happening.... i really dont want to send it off for someone to program it and then get it back and its not workin again due to the pic being buggered again from shipping and scanning...


on another note i can actually see the method above being used . looks very simple actually. just take a chunk of magnet put it to rotating disk and attache the circuit board with a shaft big enough and long enough to accomodate it. binger sensor and magnet hookup and rocknroll.. mind you i already have mine all together but still it looks simple... on a 3 slot disc. would probly need to put a piece of magnet beside each slot however to get a good reading?

[HELINHAWAII]

I'm sorry that I can't email you a pic of the board. It's glued into the project box. The best thing I can tell you to do is to go through and check continuity of all your wiring (ie. make sure you have no cold solder joints and no shorts). Then check the schematics in the handout against your wiring job and component installation.

Edit: is your pic plugged in correctly?

[Hawk_Sport]

yes the pic is correct. or looks correct to me.... should i try and change it or leave it? i went over the schematics on both my board and mikes and its dead on ... other then that i have no clue... like i siad in a few posts ago unless i send this whole thing off to be reprogrammed unless someone wants to make me a programmer?

[kas4j]

mine will not read rpms.i have it hooked up just like the plans show.. i know the ir led is working,i can see it's on through my camera. my question is, does the sensor have an input/output side or does it matter?

[HELINHAWAII]

I don't think it matters...unless I just got lucky and hooked it up right the first time. You might check your alignment between the two. Also, the first IR led I had was one of those flat ones and I had to change it out for one of the standard looking round ones.

[falconea45]

It does matter which way the sensor goes or it will not work.

[Hawk_Sport]

it looks to me like maybe my mem button might be a factor? unclear in the pics as to where it goes on the board? i have it hooked to the pic pins 7&6.... could this be a factor?
what pins does this goto? mem button on 5&6, 7&8 or 10&5


if i get all the parts for a pic programmer (wich i can get) will someone build it for me minus the board of course as i do not have that?