Lower RF signal strength?

[player80]

Hi,

how can I lower the signal strength of an RF input (100-1000mhz -- television)? I'm currently using an attenuator which works well but can such a filter also be built with resistors and/or capacitors?

 

[barry]

Your attenuator is probably just "resistors and capacitors". In fact, it's probably just resistors. You just need to match your impedance, probably 75 ohms.

 

[player80]

Your attenuator is probably just "resistors and capacitors". In fact, it's probably just resistors. You just need to match your impedance, probably 75 ohms.

Can you recommend any source where I can get further information how that can be done correctly?

 

[Audioguru]

Why do you want to reduce the signal strength of your received TV signal? Your TV is supposed to have an AGC circuit to do that.

 

[D.A.(Tony)Stewart]

A question is usually best answered when it has all the requirements. reasons, Input & output power levels, user controls , impedance ( 75 typ) , physical and other constraints.

 

[chuckey]

A resistive attenuator actually dissipates the unwanted signal as heat! Now Cs and L can't do this so the best you could do is to build a filter that rejects the "unwanted" signal. It also has the problem that is, you want a constant loss over a wide band then the filter will get extremely complex and the unwanted signal that are rejected can cause ghosting (reflections), resistors are also cheaper then Cs and Ls.
Frank

 

[barry]

Can you recommend any source where I can get further information how that can be done correctly?

Simply use a T-network for attenuation and impedance matching. 3 resistors. Look it up.