help need:38khz ir transmitter using multivibrator

[aruna1]

We've already been through this - according to the datasheet it doesn't support continuous signals, it will drastically reduce it's range in their presence as with other TSOP's.

my bad.but this will work for me as i don't use it to send data

 

[marcbarker]

As I understand from earlier postings, the TSOP requires 'gaps' in the recieved signal, if not it 'gets used to' the incoming signal and then ignores it. Therefore, the TX 38 kHz signal (2nd osc) needs to be gated on/off periodically (1st osc), and for long enough time to allow the TSOP to 'recover'.

Maybe having a TSOP solution isn't so elegant as we think it is. As the output will also be this 'long enough time', the output may need to be pulse-stretched with a monstable of some kind, adding to the circuit complexity.

 

[aruna1]

Maybe having a TSOP solution isn't so elegant as we think it is.

As I understand from earlier postings, the TSOP requires 'gaps' in the recieved signal, ff not it 'gets used to' the incoming signal and then ignores it?

I take this as meaning there needs to be the TX signal is gated off periodically for a certain time. This 'certain time' may need to be pulse-stretched with a monstable of some kind, adding to the circuit complexity.

single pulse is enough for me.remote is going to work like a on off switch but with speed control

 

[marcbarker]

single pulse is enough for me.remote is going to work like a on off switch but with speed control

Somehow I got the idea this is a beam-break system, that uses a continuous unbroken signal.

 

[Hero999]

It is, I don't think the OP understands that the frequency of the pulses needs to be higher than once every minute for the IC to work.

 

[JakesSA]

For the transmitter perhaps use a low voltage 555 see 555 timer IC - Wikipedia, the free encyclopedia for a few options?