https://forum.microwaves101.com/categories/12/filters-and-passives/feed.rss Wed, 22 Jul 2026 11:27:34 Z Filters and Passives - Microwaves 101 Discussion Board en https://forum.microwaves101.com/discussion/232/waveguide-question-splitting-and-combining Mon, 17 Feb 2025 18:40:10 Z SM4RZW 232@/discussions Hi all, I have a WRD180 double-ridge source, 18-40 GHz. But I'm using WR42 and WR28 of historical reasons for passing the signal on. There are adapters from WRD180 to WR28/WR42, but is it a more clever way of doing this, making a duplexer? WRD180 magic tee and two adapters to WR42/WR28 ? BR Lars https://forum.microwaves101.com/discussion/227/bagley-power-divider Sun, 03 Nov 2024 18:25:38 Z UnknownEditor 227@/discussions Does anyone know of the origin of the Bagley "polygon" power divider? I can't seem to find any reference to it on IEEE explore. Gotta give credit where credit is due! Steve https://forum.microwaves101.com/discussion/30/0db-attenuators Tue, 05 Sep 2023 01:40:42 Z Admin 30@/discussions supernano created the topic: 0dB Attenuators I noticed most companies that sell RF attenuators have 0dB versions. What's the point? For what applications do people use these? https://forum.microwaves101.com/discussion/208/surface-treatment-on-aluminium Fri, 14 Apr 2023 17:08:45 Z SM4RZW 208@/discussions Silver on Nickel on Aluminum is classical for uwave parts. But has anyone tested those Cr-containing corrosive protectant coatings, like Surtec650 ? Bulk resistivity, permeabilty -> effective skin depth... My gut feeling is that it will be bad... https://forum.microwaves101.com/discussion/196/pa-input-protection-pass-pulsed-rf-and-block-cw Fri, 26 Aug 2022 11:25:21 Z pmiz 196@/discussions I have a pair of 1600W amps that we want to put together in a chassis as a balanced pair for high RF power testing. The amps can only handle pulsed RF input signal up to 10% duty cycle. I am looking to see if anyone has done anything like this before. Mostly to see if there are any "COTS" type... https://forum.microwaves101.com/discussion/183/phase-noise-from-a-splittercombiner Thu, 21 Jul 2022 14:50:51 Z Eamon 183@/discussions Hello folks, I'm working on a project where I'm reproducing a design that runs at 3GHz and uses a 2-way power splitter. Previously used was an expensive (now discontinued) Holzworth HX3300 "Ultra low phase noise" power splitter. This Holzworth part has the following specs (to give a rough idea; of... https://forum.microwaves101.com/discussion/167/standard-topology-for-sma-attenuators Sun, 02 May 2021 18:21:41 Z JP22 167@/discussions I noticed the circuit topology is never mentioned in datasheets of SMA attenuators. Will they mostly use a standard one or do all companies use different "proprietary" ones? https://forum.microwaves101.com/discussion/152/coupler-design-question Tue, 08 Dec 2020 00:21:48 Z Franklin1 152@/discussions I've been tasked with creating a 4-way coupler that has equal power in 4 ports. There are other specifications but my first question comes from if I should use a rat-race, branchline, or some sort of hybrid model. https://forum.microwaves101.com/discussion/130/frequency-selective-power-limiter Wed, 18 Nov 2020 19:01:17 Z Magneto 130@/discussions Hello! My DUT creates two signals: (1) ~4GHz, -30dBm and (2) ~8GHz, +15dBm. I need to pass the low-power signal (1), while blocking or at least trimming the highpower signal (2) down to 0dBm. Is there a way without resorting to a low-pass filter? Would a broadband power limiter also trim the weaker... https://forum.microwaves101.com/discussion/126/vias-around-cpw-to-supress-resonance-modes-on-pcb Thu, 18 Jun 2020 05:58:55 Z JP22 126@/discussions I am designing a PCB to interface with a smaller chip that has CPW-based RF circuits operating at 5-10 GHz. The PCB will have SMP connectors at the edge, with CPWs routed to the center where they will be wire bonded to the CPWs on the chip. It is a single layer PCB with a metal-plated backplane. I... https://forum.microwaves101.com/discussion/114/n-stage-wilkinson Sun, 26 Apr 2020 19:13:57 Z ana 114@/discussions I would like to know the theory behind the multistage Willkinson calculator that uses the chevischev impedance transformation. Regards https://forum.microwaves101.com/discussion/110/lumped-filters Wed, 01 Apr 2020 16:19:44 Z Jyoti Gupta 110@/discussions There is a comment under lumped filter that You can obtain 10%, 100% or more bandwidth with lumped element filters. I am learning about it and i was wondering how can you get more than 100% out of anything. https://forum.microwaves101.com/discussion/101/in-a-search-for-a-specific-article Sun, 22 Mar 2020 19:22:45 Z Oz Sorkin 101@/discussions Hi, I'm working on my thesis and I've been seeking for quite some time an article and couldn't seem to find it anywhere. The article is: Shelton, J. P., J. Wolfe, and R. Von Wagoner, ‘‘Tandem, Couplers and Phase Shifters for Multi-Octave Bandwidth,’’ Microwaves, Vol. 4, April 1965, pp. 14–19. I've... https://forum.microwaves101.com/discussion/93/thick-film-resistor-materials Sat, 26 Oct 2019 17:33:27 Z Glyn Adgie 93@/discussions On the page describing thick film resistors, it is stated that the resistive element is based on carbon. As far as I know, this is not true for any new components that you can buy. My information is that a metal oxide is used. I have seen Ruthenium oxide mentioned for this application. In the days... https://forum.microwaves101.com/discussion/59/narrowband-filter Wed, 02 Jan 2019 19:07:48 Z stich 59@/discussions Hi I d like to know what is the best filter technology to get very narrowbarrow at High Frequency . For example what is the best technology to have 2MHz BW @ a frequency higher than 10GHz ? Thanks https://forum.microwaves101.com/discussion/60/summation-of-ultrashort-pulses Fri, 16 Nov 2018 05:03:39 Z Aleksey Elfimov 60@/discussions Hello. I need to sum short (~ 1 ns) pulses. Such pulses have a rather wide spectrum (several GHz). Initially, I want to get a larger amplitude impulse. That is, add 2, 4 pulses to get one with a large maximum value, but approximately the same duration. I am thinking of using Multistage Wilkinsons... https://forum.microwaves101.com/discussion/51/tuning-l-and-c Tue, 02 Oct 2018 23:02:11 Z Prakhar 51@/discussions Hi Can anyone help me understand the following? In A RF system how to identify which L and C to tune ? Does this depend on the parameter we chose to improve for ex: I want to improve my return loss i tune one L or C , then to improve some other parameter do i have to tune the same L and C or... https://forum.microwaves101.com/discussion/31/3db-hybrids Sat, 21 Jul 2018 03:21:29 Z Admin 31@/discussions Desert Sage created the topic: 3dB Hybrids I know I should know about this or be able to figure this out for myself. But I am feeling lazy today. Is there a mathematical relationship between isolation and phase and amplitude imbalance in a 3dB hybrid coupler? Or even, does high isolation guarantee... https://forum.microwaves101.com/discussion/29/mw-power-divider-wpd-gpd-bandwidth-extension-techniques Sat, 21 Jul 2018 03:15:58 Z Admin 29@/discussions kakh6739 created the topic: MW Power divider (WPD, GPD), Bandwidth extension techniques Hello, I am comparing the performance of different power dividers for LTCC substrate at Ka band. For that I am trying different existing BW extension techniques. In the bottom of the page of wilkinson power... https://forum.microwaves101.com/discussion/28/striplineburied-filter Sat, 21 Jul 2018 03:13:48 Z Admin 28@/discussions Colin created the topic: stripline(buried) filter?? I was thinking of making a filter buried between the ground plane/power plane to avoid radiation. All the filter's I've ever seen/designed were built on microstrip such that they were visible- I'm wondering if that's a good/bad idea and if...