Hello.I need to create a 37.9kHz pulse for a infrared beam sent to a infrared receiver. Is there a better way than using a 555 timer chip? I need to use 2 or 3 irLEDs to receivers 1 metre away.
I figured that out pretty quickly when playing with the pwmout wizard when it gave the same settings for two different frequencies inputted.Haku, you should be aware that PIC's PWM cannot produce every frequency under the sun.
It seems looking at the later posts that I did not see it might not be that big a deal.Would it not be best to give the big picture?
What, exactly are you trying to achieve?
I actually had them working using 38khz receivers, but in a much more complicated setup several years back. I didnt seem to have any trouble if I put them inside a tube and drilled holes to line up with the IR leds.But it was only to the stage of getting 4 separate signals to trip on a receiver using holtek chips. I never got any further than that at the time.If this is for outdoors, IR may not even be a viable option. IR receivers get swamped pretty easily even by indirect sunlight. Ultrasonics may be a better route.
I have actually read your excellent summary and i am using the circuits described. The difference is I am not using it for communication. I am using it as a beam. your article describes why I am using 38kHz receivers. Not all receivers work the way I need them to. some only work for a short duration, like a "burst" transmission. I need them to stay low for a long time, as long as the beam is not broken. I think I will probably use the setup you have for more than one IRLED on an 08M2,- or possibly use one of the 08M smd boards that rev-ed kindly gave me with some orders@marzan
Have a read of this basic IR tutorial I posted. It will give you some insights into various aspects of IR comms.
@Dippy,can you point me to any ifo on the "roll your own" solutionExample Solutions.
1. Pulse the modulated beam and use 'missing pulse' methods in the Rx end.
2. Find one that is happy with continuous beams.
3. Roll your own receiver (my own method in a long beam setup).
lol he must go to bed early they`re 2 hours behind us here in S.A.Just so you don't get Westy out of bed to answer...
that`s what I meant but couldn`t think of the correct term.I would have to change the value of the resistor I imagine to allow for the extra current?If not there is no reason why you can't run paralleled LED+R x3. (Note LED+RESISTOR).
Hi Marz,they`re 2 hours behind us here in S.A.
Allan you are right. It pisses you off at times. Some states don`t do daylight savings at the same time. It confuses me and I live here!!Hi Marz,
Don't you mean 2.5 hours, since you guys in S.A. seem to like a half-hour offset relative to nearly everyone else in the world?
Wow, Alan. You're up with your time zone details! Actually, we Western Australians like to think we are 21.5 hours ahead of South Australia and 21 hours ahead of the Oz east coast (summer time of course).Don't you mean 2.5 hours, since you guys in S.A. seem to like a half-hour offset relative to nearly everyone else in the world?
Hi marzan,@Westaust55. In the diagram on the IR tutorial under the heading 6.2 Higher power/longer range. could I alter the resistor between B.5 and the transistor to enable the use of 3 LEDs and resistors?
No - had never heard of the group, but in searching I see it is related to model boats.(O.T do you have any connection to Task force 72?)
To add to the possible confusion in Western Australia in the region from just to the east of Caiguna through Madura, Mundrallia and on to the WA/SA border there is a time zone known as "Central Western Time Zone" of UTC+8:45 so 45 minutes ahead of the rest of Western Australian and well warranted due to the earlier sun rise/sunset times for that zone/region relative the Western Standard time for the rest of WA.IWP,
HAPPY NEW YEAR
Now thats 2.5 hours ahead of you, and 2.5 hours you need to catch up for the year, and should you still feel the West is behind the central time by 21.5 hours, all can only say is its a difference in your mind, because Australia aint that big for it to take 21 hours for the sun to cross to reach you.
Yer gettin' like the farmer who complained (over 20 years ago) when metrication occurred.I just hate daylight saving time, the birds wake me up an hour earlier, my tile floors fade much faster with the extra hour of sunlight, and my solar panels make too much power to early in the day.
Be careful what you wish for - no PICAXE chips 20 years agoWhy do man need to mess with a thing like time? (although if they wound the clock back 20 years i could handle that)
Yes i had considered that, but optical interests was priority 20 years ago, and not needing a micro to stimulate the mind back then.Be careful what you wish for - no PICAXE chips 20 years ago