P
Pico
- Jan 1, 1970
- 0
I have a 40Mhz transmitter and a 433MHz receiver with their antennas about
4" apart.
When the 433 rf input signal is weak the 40MHz is swamping it.
I can't move the devices apart, they are on seperate power supplies and
there is no electrical connection between them.
The pcb's follow convention for immunity (i.e. mostly ground planed) but
it's not enough.
The troublesome RF is entering the receiver circuitry via the antenna, not
the power supply or i/o connections.
I cannot alter anything on the 40 MHz transmitter for legal reasons -
affecting it's certification.
I was wondering whether I could build a highpass filter of some kind on the
receiver antenna input but don't really know the theory.
Anybody please?
Thanks
Wilbur
4" apart.
When the 433 rf input signal is weak the 40MHz is swamping it.
I can't move the devices apart, they are on seperate power supplies and
there is no electrical connection between them.
The pcb's follow convention for immunity (i.e. mostly ground planed) but
it's not enough.
The troublesome RF is entering the receiver circuitry via the antenna, not
the power supply or i/o connections.
I cannot alter anything on the 40 MHz transmitter for legal reasons -
affecting it's certification.
I was wondering whether I could build a highpass filter of some kind on the
receiver antenna input but don't really know the theory.
Anybody please?
Thanks
Wilbur