Detect RF pulse to start a ramp voltage

[Danyc]

Hi all,

I have a continious signal of 1,5V with a repeat RF pulse . I need to start ramp voltage during the RF pulse. How can synchronise the ramp voltage on the RF pulse. Fréquency of signal is 500 HZ an the RF pulse has 0,8 ms duration. Frequency and duration would be change for other experiment.

Have you got idea to help me

Thanks

[Danyc]

Member

Message 2 sur 2

Visualisé 1 fois

Nobody can help me ?

Here a copy of the signal that i need to treat. I need to made ramp voltage (1 or more) during the RF pulse.

[rpursley]

First thing I would do is add some external circuitry to turn the RF pulses into a pulse. The easiest way to do this is use a diode to rectify the signal and then filter it to remove the higher frequency stuff. You would only need a simple AM demodulation circuit. A resistor around 1 kohm and a capacitor of 1 uF should be enough.

If this doesn't give you the kind of response you need, then a more complicated approach might work.

1. Maybe amplify the signal

2. Use a comparator to turn it into a digital signal

3. Use a one-shot in retriggerable mode to get the envelope of the signal

Hope this helps some.

QUOTE (Danyc @ Feb 7 2009, 12:11 PM)

Member

Message 2 sur 2

Visualisé 1 fois

Nobody can help me ?

Here a copy of the signal that i need to treat. I need to made ramp voltage (1 or more) during the RF pulse.