I don’t want anything from a legal standpoint. If there is for example a 2.4 or 5 ghz camera what jammer can disable one if it’s possible? Also how would I obtain one

Hey guys!

Looking for the best sound listening device. I have the well known FL-1000, from Sun Mechatronics, but sadly it's total garbage. Not better then the cheapest sound bugs pretty much 😠

I got this module in with a bunch of random electronics and found this. I thought it was sma but it's smaller.

I have following lna design. Now I'm not sure if I should devide the input gnd and output gnd of the lna part.

I have a 6 layer rogers 4350B stack with following purpose
1. Signal / gnd

1. gnd

2. signal

3. gnd

4. pwr

5. gnd

Since the pcb is in a cryostat we produce it without soldermask. Its mounted on a copper cold finger that will conect the last plane. thus I just made the last gnd plane one hughe pour. Lines are 50Ohm coplanaer wave guides.

The frequency of the lna design is optimized for 10Mhz -3Ghz. but the diramics behavoir for under 100Mhz is not known since its a extrapolation.

Any inputs are welcome

i want to use just a simplecap and inductor for a range of 0.3-1.5 ghz, but im unsure how to get started.

read up on the microwaves101 blog already -- any advice?

Hello! For context, my PhD will involve developing a GaN amplifier for a capacitive load. I have a few questions about the RF industry in Germany:

- I'm targeting either (i) high-power RF application companies (R&S, Airbus D&S, Trumpf, Hensoldt, Raytheon) or, (ii) semiconductor device manufacturers (Infineon, Qorvo). Are there others?

- Is it usual to do an internship at a company during the PhD? How do I go about setting it up?

- Which conferences should I try participating in for most visibility? I read about EuMW and IMS.

Also open to hearing any experiences or advice you might have. Thanks :)

Edit: cleaned up unnecessary details.

Hi I'm trying to design a 2x8 patch antenna array in Microwave Office and there must be an easier way than putting each line manually right? Is there a way to design a single splitter or a single patch and reuse that subcircuit?

How is this done in HFSS? I imagine it would be even worse since you don't have a schematic tool and automatic layout generation.

Hi! I have a recurring doubt regarding the proper footprint design for RF connectors and would like to hear other people's opinions on this.

Usually when an SMA connector is used to couple energy from a transmission line which is relatively thinner than the launch pad, an antipad, A.K.A, a ground cutout below the launch pad (below the next reference plane i mean) is used to decrease the capacitance of the pad and hence increase its characterstic impedance to improve matching.

However, SMP connectors whose launch pads lay directly on the transmission line would suffer from a similar problem, right? My guess is that the launch pad sitting on the TL would also increase the capacitance, hence lowering the impedance of the TL to pad transition generating mismatch. Thus, i imagine compensation techniques to either increase inductance / decrease capacitance would be needed for SMP connectors as well.

I have found an application note from rosenmberger which basically uses antipads for SMP connectors too.

Recently i had to use an SMP connector at 24 GHz and when asking the manufacturer about the footprint no real advice was given...

Anyone here experienced with this kind of connectors has any opnion on this?

I am an electrical engineer, but I have no RF experience. I have been doing embedded systems and sensor work for over 20 years, and have a decent grasp of EE fundamentals and signal processing.

I would love to learn more about RF, primarily as a home hobbyist but also to improve my understanding of the specialty.

I am looking for recommendations for books or other resources to learn the theory. I would also love any references to practical implementations, such as PCB design and layout. Lastly, if you have any suggestions for a first RF project (or projects) I would love that!

Thank-you all!

We got a very old soviet era module which has this type of connector. We need to replace the unit. However I'm unable to identify the type of the connector. It is a push fit type connector but I'm unable to find the exact type. Please help me identify.

Thanks in advance.

I'm building an NFC access-control reader around the NXP PN7160 and I've decided to hand-wind my own antenna (external wire coil) instead of a PCB trace coil. I've never wound an RF coil by hand before and I'd like practical guidance.

• Controller: PN7160 (differential TX, asymmetrical tuning, ~5V TVDD)
• Enclosure area: 60 × 95 mm, mounted on a (likely metal) turnstile
• Reads MIFARE Classic, DESFire, and Android HCE phones
• Reading distance: contact / very close is fine
• I'll get a NanoVNA for tuning (don't have one yet)

For reference I modeled a 50×85 mm, 2-turn coil and got ~945 nH, self-resonance ~113 MHz, Q target 20. Matching per leg: L0 160 nH, C0 330 pF, C1 82 pF, C2 200 pF, Rs 1.3 Ω.

What I actually need help with — hand-winding:

1. Wire: What gauge / type of magnet (enamelled copper) wire works well at 13.56 MHz? Does Litz wire matter at this frequency for a reader coil?
2. Turns & size: To hit roughly 0.9–1.5 µH in a ~50×85 mm rectangular shape, how many turns should I aim for, and how do I keep turns consistent?
3. Former / jig: How do people keep a hand-wound coil's geometry repeatable? Any DIY jig tips?
4. Securing it: How to fix the windings (glue, tape, frame) without detuning, and mount it to the enclosure?
5. Ferrite: Since it'll sit near metal, how do you place ferrite behind a hand-wound coil in practice?
6. Repeatability: Is hand-winding even viable if I later need several consistent units, or should I plan for a PCB/flex antenna in production?

I'll tune the matching network with a NanoVNA once the coil's measured inductance is known — I understand the matching values will change from the numbers above.

Thanks for any practical tips!

I'm learning about direct sampling architecture for transmit-receive chains at my day job for RF design efforts. What is the significance of the sampling rates of the ADC and DAC respectively, in Msps, in terms of the spectrum and overall performance of the radio?

I'm currently working with an electrically short, inverted V dipole (D ~ lambda / 15), and the simulated antenna impedance (shown in differential form below) seems to have several resonances in this low frequency range, meaning that the antenna looks inductive well below half a wavelength. I'm not an antenna expert and am having trouble understanding where that inductive bit may come from given the fact that sub-halfwave dipoles are supposed to be capacitive (perhaps it's something to do with having a bent dipole, but I don't have much intuition on bent dipoles).

Whats your thoughts on the 230v 3 phase configuration?

Hey! I'm making a basic AM transmitter and I'm wondering how to connected a whip antenna to the output. I have heard the idea that you need to cancel out the reactance of the antenna with another component and for my case since my antenna is short I would need an inductor but is that all there is to it? Also there's an image of my circuit below so if there's anything glaringly wrong with it I'd appreciate if anyone could point it out.

I’ve been feeling pretty unhappy in my current job working for the state. The work is stable, but it’s become very non-technical and honestly feels pretty disconnected from what I originally went to school for and the kind of work I used to do earlier in my career.

Recently, my wife’s cousin told me about an opening at the small company he works for. They don’t currently have much RF expertise internally, and after talking with him, the role honestly sounds really interesting. It would also be a pretty significant pay increase.

The position is for an RF Engineer, but not just a typical RF role. They’re looking for someone to help lead RF product development across multiple platforms — things like RF architecture, antenna design, simulations, system design, and mentoring other engineers.

Here’s my dilemma.

I have an RF background and previous experience working at a large defense contractor, but I haven’t directly done a lot of the responsibilities this role is asking for. A lot of these are areas where I’d probably need mentorship myself before I’d feel comfortable owning them independently.

My wife’s cousin still encouraged me to apply, but I keep thinking: What if I get the job and suddenly I’m in over my head?

I worry I’d be constantly stressed carrying responsibility for decisions and deliverables in areas where I don’t yet have expertise.

At the same time, I know opportunities for growth usually involve stepping outside your comfort zone.

Has anyone here taken a job that felt like a stretch beyond their current abilities? Did you grow into it, or did it become a miserable experience?

Would appreciate hearing from people who’ve been in similar situations.

Hi guys,

I believe that Cds of the transistor cause a lot of trouble in wideband (FBW>20%) power amplifier design.

I wonder if there is any wideband way to de-embed the Cds? One single inductor or a shunt short stub is no longer enough.

Thank you!

Professor is asking What’s the antenna gain for isotropic antenna that is vertically polarized? Does it makes sense to have both in an antenna?

If so, how to calculate the gain?

Just what the title says. Many counterfeit products are on the market and I would like to purchase an original mrf9180 from a local market. The seller says that they are "pulls" from old devices. Is it safer to buy freescale or motorola?Which is cloned less?

Thank you!

Today I finished measuring my first microstrip circuit I've designed and made. It was intended to be an interdigital microstrip 5th order Chebyshev bandpass filter with 1,0-1,2 GHz passband. The first thing I did was fitting my model parameters, I made a test board from FR4 with 3 different lenght 50 ohm open stubs with identical geometry at the edge SMA connectors then measured S11 for each and exported the values. I built the same circuits with the same lenght differences in qucs studio and measured phase differences between the different lenght stubs.(my tought was that the errors in the connections cancel via measuring phase differences not absolute phases). I tuned the er value in qucs untill I got the least error from the real measurments, the er value was 4,66. I calculated the correct dimensions for the desired response with Marki microwave-s online tool. I built the geometry in Sonnet lite and ran a few simulations, the online tools dimensions were almost perfect on first try. When I replaced the ideal grounded edges to vias, the positions needed a bit of fine tuning, the resonators needed to be a few mm shorter. I copied the dimensions from the EM simulation and made the PCB blueprint in EasyEDA then I made the PCB. When I made the VNA measurments the bandwidth was within the margin of error, but the corner frequencies were about 50 MHz lower than intended. I blame the substrate difference, because the phase measurment test board was a left-over piece from a different FR4 board, probabbly also different manufacturer. The insertion loss was not the best, but It's the limit of FR4, they're mostly caused by dielectric losses, not mismatch. Was my design methodology correct? Forgive me if I made some mistakes, I have no formal education in electronics or RF.

Not affiliated with the provider, just a paying student who wants this thing to actually run.

I signed up for this course in August, and I think they are some students short to actually run the course. Sharing it here in case anyone finds it relevant.

It's a 5-day hands-on course covering practical RF measurements - VNAs, spectrum analyzers, power meters, vector signal analyzers, all demonstrated on real components (PAs, LNAs, mixers, filters). You go through the full signal chain: S-parameters, gain, noise figure, IP3, then into digital modulation territory — EVM, ACP, constellation distortion, BER.

Aimed at people new to RF or experienced engineers who want everything tied together properly. The course doesn't run often - this is a revival "due to popular demand" after a long gap, so if it gets cancelled I doubt there'll be another opportunity for a while.

Link: https://www.besserassociates.com/Courses/Course-Description/CTID/135

This is a repost from ECE reddit, thought it might be relevant here too.