📡 What is Microwave Engineering?

👉 Click here: https://engineersheaven.org/forum/topic/46
to visit our website and read the full article.

#MicrowaveEngineering #RadarTech #WirelessInnovation #TelecommunicationEngineering #SignalProcessing #RFengineering #AntennaDesign #FutureTech #STEMeducation #EngineersHeaven #EngineeringExplained

Don’t you just love it when vintage RF electronics springs back to life? 😃

My old fox hunt receiver, original design by #OZ1FSM, has survived a couple of relocations, but the batteries had leaked and it looked like a complete loss, unfortunately.

A couple hours of careful cleaning did the trick however, and now it’s back, alive and well with new battery holders and a couple of Lithium’s 😃

#hamradio #foxhunt #RFengineer #RFengineering #testandmeasurement

Spiral antennas are funny devices. They are known for their extremely wide bandwidth, the ones shown here, are specified to operate from 2-18GHz.

They’re not meant as transmitting antennas, these critters are receive-only, used by (largely non-civilian) pilots who have those needs ☺️

Their low frequency boundary is determined by its physical size, in this case, the circumference of the small plate where you can see the fine spiral traces.

Once you cross below that boundary, the structure basically collapses electrically, seen here as a steep SWR ‘wall’ to the left side of the sweep.
At this point it’s not an antenna anymore, but something else (whatever that is 🤷🏼‍♂️😂)

#rfengineering #rfengineer #testandmeasurement #hamradio #hamr #antennaengineering #emso

Testing a new 1:9 Unun I plan to use for a permanent non-resonant multiband vertical 🙂

#hamradio #testandmeasurement #measurementmonday #rfengineer #rfengineering #hamr #electronics #hamradiooperator

In November 2023, I experimented with directional finding using a ‘rat race’ 4 port coupler. The coupler outputs deliver the sum and difference of the received signals from the two antennas and at the difference (‘DELTA’) output, a reasonably sharp signal ‘null’ is present exactly between the antennas.

In principal this should also be doable by comparing the RSSI (signal strength) between two completely similar receiver chains.

Using two AD8317, wideband demodulating logarithmic amplifiers and two antennas, the DC voltage on the output can be displayed on the oscilloscope (yellow and blue trace), and more importantly, the difference (‘DELTA’) between them (red trace).

Moving an RF source in front of the antennas, it’s clear that the DELTA signal drops when the source is right between them, and rises again towards the edges.

RF filtering will be needed to limit the AD8317 10GHz bandwidth 🙂

#hamradio #rohdeschwarz #testandmeasurement #rfengineering #rfengineer #emso

2/2)

I decided to test it with a 0dBm RF source through an isolator and it clearly reacts to the small amount of applied power, moving from 2480 Ohm down to 2438 Ohm.

Any suggestions for more experiments? 🙂

#rfengineer #rfengineering #electronics #testandmeasurement #sensorsunday

1/2)
A fellow #hamradio operator and electronics enthusiast brought me a vintage X-Band power sensor, thanks OZ1ETE 🙂

It has a super sensitive NTC Thermistor, a tiny spherical bead, encapsulated inside a small glass tube. It’s by far the most sensitive Thermistor I’ve ever seen, just holding your hand in front of the waveguide flange, not actually covering it, will make it change slightly.
#rfengineer #rfengineering #electronics #testandmeasurement #sensorsunday

💡 Need more personalized help? Is your challenge more complex or unique, involving different specifications or circuit types?

🎯 We’ve got you covered!

🚀Don’t wait—contact @innowave for a quote on your RF circuit or radio design problems: https://buff.ly/3NPPCcn

🚀Contact @innowave for a quote on RF Circuit design and Measurement Training and Consultancy. https://buff.ly/3CcvzlY

#RFDesign #RadioFrequency #Electronics #PowerAmplifier #LNA #KeysightADS #RFEngineering #CircuitDesign

💡 Need more personalized help? Is your challenge more complex or unique, involving different specifications or circuit types?

🎯 We’ve got you covered!

🚀Don’t wait—contact @innowave for a quote on your RF circuit or radio design problems: https://buff.ly/3NPPCcn

🚀Contact @innowave for a quote on RF Circuit design and Measurement Training and Consultancy. https://buff.ly/3CcvzlY

#RFDesign #RadioFrequency #Electronics #PowerAmplifier #LNA #KeysightADS #RFEngineering #CircuitDesign

Believe it or not, approaching 40y as a #hamradio operator, I just got my first BIRD wattmeter 😃

Its in really nice shape, S/N 104908, I wonder how old it is 🤔

The hunt for ‘slugs’ 🐌 has started 🙂 It came with 50W 2-30, 25W 100-250 and 250W 400-1000. Would be nice with 100W for the shortwave bands and something which covers 6m 👌🏼

#hamr #rfengineer #rfengineering #testandmeasurement

Always wanted a portable directional to spot emitters at higher frequencies - decided to try this one.

My test ceiling is 4GHz, but at least that far, it seems OK ✅🙂 I doubt it’ll go all the way to 10GHz as advertised because of the (FR4?) PCB Material.

It always amuses me, how violently antennas like this collapse at the lower frequencies - suddenly the size no longer accommodates the input wavelength and they simply stop being an antenna 🤷🏼‍♂️😂

For some reason, these logperiodic (LPDA) antennas always come with a SMA connector at the tip - that’s completely wrong: you need to solder a semirigid coax all the way down the centerline and feed it from there. The PCB was even prepared for it - go figure 🤷🏼‍♂️🤔

Anyway, now fixed, tested, and ready to go signal hunting 😎

#rfengineering #rfengineer #hamr #hamradio #testandmeasurement #antennaengineering #electronics #summervibes

🚀 New Video Alert! 🚀 Learn how to install HFSS on any Linux distro using Bottles. Perfect for antenna design and RF enthusiasts! 📡

Watch now: https://youtu.be/ydEOdOd2ZP8

#Linux #HFSS #Bottles #FlatSeal #AntennaDesign #RFEngineering #Antenna #RF #TechTutorial #PhDLife #LinuxInstallation #TechGuide @usebottles #flatpak #flathub @FlatpakApps @flathub @kubuntu #kubuntu #linuxMint #Telecommunications

I’ve been looking for an antenna for a permanent #meshtastic node in my attic and I found this one, along with 5m RF200 low-loss cable.

I know that this setup will most likely render me ‘excommunicado’ in the #meshtasticcommunity: “thou shalt always install thy node right below the antenna!”, but here’s the thing: I want to experiment with different hardware, I want to do some interference measurements at night (ever heard about the ‘Mammotion’ lawnmower which illegally jams 868MHz?) , AND I have a powerful 2m/70cm transmitter close to it, and I don’t want EMI issues on a sensitive 5V line.

Besides, the antenna has 3dBi gain and I measured the cable loss to 1.4dB at 868MHz, so given its better location, the numbers still come out positive 🙂

See that dip near 145MHz btw.? Need to do a test to see how much signal it’ll pick up from my VHF rig - don’t want to damage my LoRa module 👌🏼🙂

#lorawan #electronicsengineering #rfengineering #rfengineer #hamradio hamr #testandmeasurement

It’s #measurementmonday and I’m investigating a mystery coupler, a fellow ham asked me to test.
It seems to be the happiest around 1.8-1.9GHz 🤷🏼‍♂️🙂
The coupled ports are -20dB down.

What’s even more interesting, is the detector diode add-on it came with: you carefully insert the diode, a 1N21E replica, directly into the center pin of the N-connector 😳 Then carefully mount the outer capacitor shell with the BNC connector and you’re good to go.

Since the diode now sits in its reversed position, the output will be negative and it works just fine 👍🏼🙂

#testandmeasurement #hamr #hamradio #rfengineer #electronics #siglent #rfengineering

It’s time to answer my #easterquiz: it’s a ‘sweeper’, some would call it ‘Jammer’ 🤷🏼‍♂️🤓

They come in all kinds of frequency bands and output power levels - be aware they may be illegal in your country. I ordered this to operate in a band covered by my #hamradio license and I have no intentions of ever transmitting into an antenna.

In short, it uses a 555 timer to generate a 100kHz ramp signal which is fed to a 400-500MHz VCO. Center frequency and bandwidth can be adjusted by two trim pots. The output signal is then amplified - that’s all there is to it 👌🏻

I fed the output through a 30dB high power attenuator, then split it to my spectrum analyzer (through another 20dB) and a detector diode to my oscilloscope.

It’s not a completely calibrated setup, but the measurements seem to agree at about 1W ‘channel power’. Not much, not very efficient, but it works just fine 🙂👍🏼

Hope you enjoyed it 😃😃

#testandmeasurement #rfengineer #rfengineering #electronics #siglent #rohdeschwarz #hamr

🐣 #easter #quiz #2: A few hints 🙂

#electronicsengineering #rfengineering #rfengineer #hamr #hamradio #eastereggs #easterfun

If there’s an application where a good old analogue oscilloscope will deliver right away, it’ll have to be the classical #hamradio two-tone modulation test 😃

Using the #Cutegen™️ and a resistive mixer, I’m modulating a #yaesuft817 with two tones: 700 and 1900Hz, observing the resulting RF signal on a spectrum analyzer and the oscilloscope.

A simple and traditional way to detect unlinearities and observe transmitter performance. And it’s an absolutely beautiful picture on the oscilloscope screen ☺️❤️

All time RF engineering and #hamr classic 🙂

#signalsaturday #testandmeasurement #rfengineering #rfengineer #electronics #electronicsengineering

It’s #waveformwednesday, let’s make it #vintagewednesday as well 👴🏻😃

I’m assembling a small low pass filter and I want to sweep it from 100Hz to 10kHz. Let’s do it the old fashioned way ☺️

Before modern oscilloscopes with BodePlot options became available for everyone, a common and quick way to sweep a circuits frequency response, was to connect an external sweep generator and look at the resulting curve on the screen.

Using the #CuteGen™️ I’m sweeping logarithmic from 100Hz to 10kHz. I’m using the generator trigger output as trigger on channel 2 and the X-axis is adjusted to be exactly one period, i.e. 100-10KHz.

The filter response can clearly be seen 🙂

This method still has its justification. Not everyone has fancy scopes and even if they have, it’s still a smart and fast way to quickly observe a frequency response. Show me any fancy scope updating a bode plot every 100ms 👌🏻🙂

#testandmeasurement #hamr #hamradio #rfengineering #rfengineer #electronics #electronicsengineering

It’s #signalsaturday and I’m continuing the #CuteGen™️ test series by looking a bit at the harmonics 🙂 How clean is it?

Starting at 1kHz I’m using my #Siglent #oscilloscopes powerful FFT functionality and with harmonics >60dB down, this little thing really is a decent audio function generator.

I then moved to the spectrum analyzer and did some tests at (much) higher frequencies. Only included 10 and 30MHz here, but pattern is clear: harmonics are generally nicely attenuated, more than 60dB, although at the high end, it’s not quite that much, more like 50dB and a sub-carrier spur appeared as well. Makes me wonder how well the 60MHz version performs 🤔

#testandmeasurement #rfengineering #rfengineer #electronics #electronicsengineering #uni-t #hamradio #hamr

Using the Agilent 52181A counter (with the HS Oven option) to measure frequency accuracy of the small UTG932E function generator.

I tried 1,10,100kHz and 1,10,20,30MHz to see if there’s some band shifting going on which could affect the accuracy.

It doesn’t seem to be the case, the accuracy is consistently around -3.5ppm across its entire frequency range. Not bad at all 🙂

This little cutie doesn’t have an external reference input, so it is what it is, however for daily use or a portable setup (it runs from a USB power bank just fine), the accuracy is certainly acceptable 👍🏼

I have other function generators which can be locked to an external reference if needed 🙂

#electronics #electronicsengineering #rfengineering #rfengineer #hamradio #hamr #testandmeasurement