decoupling cap value for 27MHz transmitter?

[horizontal]

Can some tell me what is a good value for a battery decoupling capacitor in
a 27 MHz transmitter, thanks.

 

[Charles Schuler]

Can some tell me what is a good value for a battery decoupling capacitor
in
a 27 MHz transmitter, thanks.

1/10 the impedance of the circuit to be decoupled is a typical starting
point. So, if it's a 50 ohm circuit, 5 ohms of capacitive reactance is
good. Solve 5 = 1/(2pifC) and you get 1.2 nF.

Now, on to the second part. RF designers often use multiple bypassing (one
for the mouse and one for the rat). Also, an RF choke or resistor helps a
lot. RF ferrite beads are also helpful. Bypassing as most things in
electronics can get a tad involved. Shielding is also often part of the
actual solution.

 

[horizontal]

1/10 the impedance of the circuit to be decoupled is a typical starting
point. So, if it's a 50 ohm circuit, 5 ohms of capacitive reactance is
good. Solve 5 = 1/(2pifC) and you get 1.2 nF.

Now, on to the second part. RF designers often use multiple bypassing (one
for the mouse and one for the rat). Also, an RF choke or resistor helps a
lot. RF ferrite beads are also helpful. Bypassing as most things in
electronics can get a tad involved. Shielding is also often part of the
actual solution.

Thanks a lot for that, my knowledge is very limited so that was very
helpful.