RF Filter
A wide collection of RF Filters, band-pass filters
Site Listings
Interactive Digital Filter Design
144MHz Low-Pass / 432 MHz Notch Filter
20m 30m 40m Bandpass Filters
23 cm filters
30 Meter Band Pass Filter
432 144 MHz Notch Filter
440Mhz Interdigital Bandpass Filter
50 MHz Terminating Low Pass Filter
5th order High Pass VHF Filter
70 MHz low pass filter
A 2 meter band-pass cavity using surplus Heliax
A compact 5 bands remote switchable BPF
A diode-switched band-pass filter
A home-built low-pass filter for 4m
A low pass filter circuit
About Cavity Filters
Audio CW Filter
Audio CW Filter
Band Filters
Band filters by PA9M
Band Pass Filters for HF Transceivers
Band-Pass Filters for HF Transceivers
Band-stop filter
Bandpass and I.F. Filters
Bandpass filter
Bandpass filters design
Bandpass Filters for Portable Usage
Broadcast band filter new
Cheap Crystal Filter
Clean Up Your Signals with Band-Pass Filters
Clean Up Your Signals with Band-Pass Filters part 2
Coaxial Stub Filters
Coaxial Stub Filters
Constant k Lowpass Filter Design
Contest Bandpass Filters
Curing Alternator Whine
CW Notch Filter
Design RF Filter
Double Tuned Receiver Band-pass Filter Design Center
Dual-Tuned Bandpass Filters for Amateur Receivers
Enhancing Frontend Performance with Optimized Band Pass Filters
Filtering of the Icom IC-775 DSP
Filters and Ferrites in EMC
High Pass Filters
High-Pass Filter Design
Highpass filter calculator
Homebrew a CW Filter
Homebrew Crystal Filter Design
How to make a mains filter for EMC and noise reduction
ICOM IC-775 FIlter Installation
Inrad Roofing Filter in the Yaesu FT-920
Interdigital bandpass filter designer
Interferences and filtering
K2TR Coax Stub Filters
KI5YN QLF Filter
LC Filter Design
Low Pass Audio Filter
Low Pass Filters
Low-Pass Active Filter Designer
Lowpass filter for 30m
Mains Filter for EMC & Noise Reduction
Mode J Desense Filter
Narrow Band-Pass filter for HF
Noise Bridge Tuner Tuner
Notch Filter Designer
Novel filter for sat working
Online Microwave Filter Design and Analysis
PC Board Filters
Power netfilter
Receiver Band-Pass Filters
RF filter basics tutorial
Roofing Filters
RTLSDR Coax Stub
Second-Harmonic-Optimized Low-Pass Filters
SSB and CW Filter
Stub HF filter
The Ladder Filter
The NVARC Ugly Filter Project
Tunable BandPass Filter
Tunekit
TVI Filter schematic
Use Band Pass Filters to clean up Signals
Using Band-Pass Filters
Using ferrite for interference suppression
Variable bandwidth cw filter
VHF Broadcast Passband Filter
W3LPL Receiving Bandpass Filters
W3NQN TX filters
Yaesu FF-501DX Low Pass Filter
YCCC 6 Band Receive Bandpass filter
This is an interactive filter design package, for designing digital filters
Hits: 984
| Votes: 3 | Rating: 6.67
A combined 144MHz Low-Pass and 432 MHz Notch Filter by VE2ZAZ
Hits: 741
| Votes: 3 | Rating: 1.33
Homemade LC Bandpass Filters for 20M 30M 40M In multi station environments like special events ...
By: AB2EW
Hits: 412
| Votes: 1 | Rating: 10
2 filter designs a 3-pole and a 5-pole
Hits: 432
| Votes: 1 | Rating: 1
A homemade band pass filter for the 30 meter band based on the original VE7BPO ...
By: KE7HR
Hits: 603
| Votes: 1 | Rating: 6
Combined 432 MHz High-Pass - 144 MHz Notch Filter By Bertrand Zauhar, VE2ZAZ
Hits: 520
| Votes: 1 | Rating: 1
Homebrew Amateur Radio 440Mhz Interdigital Bandpass Filter
Hits: 584
| Votes: 1 | Rating: 1
This low pass filter terminates all harmonics from the 2nd to above the 10th harmonic ...
Hits: 543
Sometimes many VHF UHF modern transceivers have problems with BROADCAST Interference and CROSS modulation from ...
Hits: 1216
| Votes: 8 | Rating: 6.12
An home made low pass filter for 70 MHz by IK0VAQ
Hits: 736
| Votes: 3 | Rating: 4.67
Cavity is often required at a busy site to not only prevent its receiver from ...
By: ka7oei
Hits: 137
| Votes: 2 | Rating: 3
These band filters are based on 3 or 5 sections Butterworth band pass filters maintaining ...
By: ON7EQ
Hits: 230
High speed silicn diodes work well as RF switches This article describes how to use ...
Hits: 2332
| Votes: 3 | Rating: 4.67
This unit uses four capacitors only two of which are variables and a single tapped ...
Hits: 594
A simple 7 element Chebyshev low pass filter rolls of at 30MHz Attenuation is better ...
Hits: 5304
| Votes: 21 | Rating: 6.1
Cavity filters are tipically circuitry behind a duplexer that allow only certain frequencies to pass ...
Hits: 475
| Votes: 3 | Rating: 5.33
A very effective AF Adaptor with built in noise blanker and 30 Hz CW filter ...
Hits: 1530
| Votes: 3 | Rating: 5.67
An home madek Audio CW Filter made simply using SMD Components
By: g4aon
Hits: 181
Experience of band filters, for a contest multi operator enviroenment
Hits: 4083
| Votes: 6 | Rating: 7.5
Band filters for PA6Z made by PA9M, designed by W3NQN.
Hits: 480
| Votes: 1 | Rating: 9
If your multiple transceiver station is suffering of intrastation interference this handy and inexpensive band ...
By: K4VX
Hits: 142
Do your multiple-transmitter field day or contest efforts suffer from intrastation interference ?
Hits: 4380
| Votes: 3 | Rating: 6.33
Wikipedia page on Notch filter, a narrow stopband - high Q factor filter
Hits: 444
| Votes: 2 | Rating: 2.5
On this page a popcorn highpass filter some inductors and their Q double tuned bandpass ...
Hits: 905
A simple project for an effective home made band pass filter designed for the portable ...
By: OZ1CX
Hits: 808
| Votes: 2 | Rating: 9
How to design narrowband bandpass filters
Hits: 811
| Votes: 4 | Rating: 2
These are QRP rated 3 Pole Butterworth filters based on a design by K4VX feature ...
Hits: 538
This project involved designing a 7 pole Chebychev broadcast band filter to address severe interference ...
By: VK3IL
Hits: 30
An economical way of building an SSB filter The circuit is for a filter with ...
Hits: 499
These inexpensive easily built filters can be the buffer you need between the signals you ...
Hits: 3654
Part 2 You re now much closer to saying goodbye to your unwanted signal problems ...
Hits: 1379
Coaxial stub filters used at W7GJ
Hits: 1137
A range of easy-to-build RFI filters
by John Regnault, G4SWX
Hits: 1334
| Votes: 4 | Rating: 9.25
Online Constant - k Lowpass Filter calculator
Hits: 454
| Votes: 12 | Rating: 3.67
Build a set of W3NQN filters for multi-operator contesting
By: KG4JJH
Hits: 676
How to create a low pass filter able to reduce or even remove the noise ...
By: KB1MVX
Hits: 518
| Votes: 2 | Rating: 9
Homebrew CW notch filter project by KN9B
Hits: 524
Hits: 1548
| Votes: 2 | Rating: 4.5
This webpage caters to EMRFD owners offering insights into building popcorn receiver band pass filters ...
By: VE7BPO
Hits: 40
This PDF article introduces a series of dual tuned bandpass filters designed for input tuning ...
By: G3RJV
Hits: 41
This article explores the nuanced design challenges of Band Pass Filters BPF in radio receivers ...
By: PA3AKE
Hits: 83
Replacing filters on ICOM IC 775
Hits: 523
| Votes: 5 | Rating: 6.4
This article is about the characteristics and use of various filters and ferrites for solving ...
Hits: 908
Understand how high pass filters are done
Hits: 605
Online high pass filter design page with introduction to high-pass filters by K7MEM
Hits: 674
| Votes: 2 | Rating: 1
Butterworth Highpass Filter Designer
Hits: 450
| Votes: 4 | Rating: 2.75
An home brewed morse code CW filter with a central frequency of 800hz and a ...
Hits: 1777
| Votes: 2 | Rating: 2.5
Desgining crystal filters and find out crystal data by measuring it.
Hits: 689
| Votes: 7 | Rating: 7
Article showing how I ve made a mains filter to reduce EMC in the electricity ...
By: Adrian Leggett
Hits: 1242
| Votes: 5 | Rating: 9.6
Inrad Roofing Filter installation instruction The IC 775 Roofing Filter Mod consists of a 6 ...
By: PA0Q
Hits: 67
Insalling Inrad roofing filter in the FT-920 with pictures and comments
Hits: 810
| Votes: 2 | Rating: 9.5
Fill out the form to design a bandpass filter as described in the January 1985 ...
Hits: 1122
| Votes: 6 | Rating: 7.67
General information on Filter passbands, interferences, TVI and RFI problems
Hits: 1174
| Votes: 1 | Rating: 10
Multi transmitter filters
Hits: 3274
| Votes: 7 | Rating: 6.43
The QLF filter is a microprocessor based interface designed to go between a standard Morse ...
Hits: 1949
| Votes: 3 | Rating: 4.67
This is an interactive design package for designing analogue i e hardware filters made of ...
Hits: 1567
| Votes: 4 | Rating: 6.75
440 Hertz peaked low pass audio filter experiments
Hits: 921
| Votes: 1 | Rating: 7
Article explaining electronic network of low pass filters
Hits: 818
Javascript filter design page with introduction to low pass filters by k7mem
Hits: 624
| Votes: 1 | Rating: 1
30m lowpass filter for the Softrock Ensemble RXTX tranceiver.
By: LB0MG
Hits: 354
This article shows how to make a mains filter that can be extremely effective in ...
By: M0NWK
Hits: 315
| Votes: 3 | Rating: 3.67
This type of filter can be used in a Mode J satellite station uplink on ...
Hits: 1160
| Votes: 2 | Rating: 5
Band pass filters can be critical components in competitive stations This setup may help put ...
Hits: 2588
| Votes: 1 | Rating: 1
Noise bridge circuit to tune your tuner
Hits: 375
| Votes: 1 | Rating: 10
Online calculator, Butterworth Bandstop (Notch) Filter Designer
Hits: 808
| Votes: 6 | Rating: 3.33
Elimiate QRM when working with satellite antennas
Hits: 484
This site is dedicated to design and analysis of micro and millimeter wave filters from ...
Hits: 642
| Votes: 10 | Rating: 6.2
Offer performance comparable to tin box filters and except for being bigger stack up pretty ...
Hits: 381
Homebrew a Power netfilter
Hits: 341
Third order Cauer filters can boost performance of multi transmitter multi operator contest stations to ...
Hits: 893
| Votes: 1 | Rating: 5
an overview introduction or tutorial about the basics of electronics filters including the types of ...
By: radio-electronics.com
Hits: 315
An Introduction to Roofing Filters by ACØC
Hits: 525
Cutting out the noise using a simple coax filter to improve the poor front end ...
By: M0NRD
Hits: 762
| Votes: 2 | Rating: 5.5
Sometimes we need a little more output filtering than traditional designs offer Look at a ...
Hits: 886
A pdf file with schematics of an ssb and cw filter AF amplifier
Hits: 2142
| Votes: 3 | Rating: 4.33
Multi transmitter filters for HF Bands
Hits: 538
Article by Lloyd Butler VK5BR
Hits: 817
| Votes: 2 | Rating: 8.5
Project to build sets of band pass transmitting filters for reducing the interference between HF ...
Hits: 1037
| Votes: 4 | Rating: 9.5
A homemade tunable bandpass filter for all HF bands from 160m to 10m
By: YU1LM
Hits: 1133
| Votes: 3 | Rating: 5.67
Filter Tuning Kit for Windows is a electronic filter synthesis program and a practical filter ...
By: Tunekit
Hits: 4830
| Votes: 10 | Rating: 5.2
A simple TVI Filter schematic
Hits: 419
Clean Up Your Signals with Band Pass Filters a two parts article published in this ...
By: W3NQN
Hits: 796
| Votes: 1 | Rating: 1
Clean Up Your Signals with Band-Pass Filters
Hits: 744
Excellent guide to using ferrite cores for interference suppression Understanding and Solving RF Interference and ...
Hits: 6204
| Votes: 6 | Rating: 9.5
As the sunspots return and DX propagation conditions to improve the age old problem with ...
Hits: 1153
| Votes: 3 | Rating: 4.33
VHF Broadcast Passband Filter (88 108 MHz) by DF9CY
Hits: 603
| Votes: 1 | Rating: 1
Project of receive only filters optimized for minimal loss and very high rejection of frequencies ...
Hits: 1091
Building the W3NQN bandpass filters
By: K8GU
Hits: 432
The FF 501DX LPF a high performance VHF and 10m filter was obtained at a ...
By: G4HSK
Hits: 16
This is a 6 band receive only filter designed to protect your receiver front end ...
Hits: 1974
| Votes: 2 | Rating: 9.5