please help me

Homework assignment?

See filter design software, such as what's in RFSim99 or the filter program at

, for help with the filter. What passband ripple? How steep a cutoff at the band edges? Do you know how to convert a low-pass filter to a bandpass? If so, you should be able to work from tables in filter books. Question for you: is it better to design it as a bandpass filter, or as a highpass and a lowpass? Amplifier: you need to supply more specs. HOW low noise? What's the driving source impedance? What input return loss do you need to achieve? What gain? What TOI and SOI? What 1dB compression point? What power supplies are available? Do you have budgets for space, power, cost? Other constraints?

If it IS a homework assignment, you may well learn more seeking answers to those other questions than from the original question itself.

janz wrote: :please help me

http://72.14.203.104/search?q=cache:PtYi-cQOinsJ:groups.google.com/support/bin/answer.py?answer=12348%26+*-title-like+doesn't-convey-as-much-*+Use-descriptive-subject-lines

You put a bunch of parts into a sturdy bag and shake it real good. Then you hand the bag to the teacher who assigned the homework.

What's the application? Why do you think you need a Chebyshev filter?

Thanks,

Frank

my lect just give me the frequency range.this BPF and LNA will connect to RF Protek 3201(spectrum analyzer). RF Protek need 12V as source. so BPF voltage output is 12V. as general this system like this........ LPDA antenna ---- LNA ---- BPF ----- Protek 3201. thanx for your help

You'd better check with your lecturer again - if you stick 12V into the Protek you risk damaging it. The LNA on the other hand is probably expecting its 12V power to be fed up the cable to it. Go check out LNA's on Minicircuits' site and then Google your filters.

Ken