After a decade, there is a mistake in the video I'd like to address: The subtle description of the doubler operation at 45 minute mark is not correct. The top and bottom of the board form a broadband balun and the tapered lower layer transforms the signal into a balanced mode into a quad pair of diodes. The signal then mixes with itself producing the doubled frequency. At the same time we don't want to self-mix down to DC and create a DC offset so the little wire is there to keep the DC voltage at 0V while acting almost like an open at higher bands - kind of like a bias-T but with a lower cut-off at >1GHz. This doubler is fairly broadband, operating at the input from 1GHz to 32.5GHz. The fundamental rejection is about 15dBc worst case, likely at the edges of the band where the balun does not have very good phase and amplitude response.

You're not only incredibly knowledgeable and intelligent, you're a phenomenal teacher. Those qualities typically lack synergism. Not only that, you are willing to take valuable time away from your life to enlighten an effectively anonymous audience for no significant monetary benefit. I'm an electrical engineer. I'm still young in my career (I'm 27), but my hunger for discovery has been present my whole life. I just wanted to thank you, on behalf of all of us.

Next week on the Signal Path Blog: How to build a communications satellite using household materials.

100GHz circuits are rather common these days. Radars, imaging circuits, ultra high-speed data converters and data communication systems, short reach and backhaul radios...

I've used your video library as a reference for years now! Thank you, Shahriar! 🙏

Fantastic topic, fantastic video. Another home run.

Thank you so much Shahriar. This was one of kind video which you can not find in other places.

This is a very good review of connectors, couplers, amplifiers, waveguides, and other microwave components! It's also very interesting getting to see inside some of these components......something you don't get to do very often in the lab..... It shows that many of these devices, such as splitters, amplifiers, and multipliers, can be designed in-house if you're on a budget......

Now that was certainly an interesting hour of video. Thank you.

Great video! As someone who works in microwave and mm wave R&D I have to say you do a great job of explaining these things in layman's terms. Good job!

This was a very good overview of the common microwave lab components. This would have been really useful to see when I was starting my grad research.

Amazing microwave show and tell. Thanks!

This video is great! I had already decided that I will contiunue my study in EE in Microwave Engineering, but of course I hadn't known that much about these things Ive never touched one except my laboratory courses because they are very expensive ! But watching you demonstrate is truely fun. Thanks, now I will go through all of your microwave related videos :D

cool RF-Stuff and very good Explanation ! the Radio Amateur,s heart is bumping

Thanks for making videos like this. They are the best.

Fantastic video, thanks. It's nice to have someone go through the real world aspects of high frequency systems like connectors and components. As an electronic engineer I have a huge amount of respect for microwave engineers. Nevertheless it's happened to me a few times that I go to a lab to test something and look like a moron because I use the wrong connector terminology or idly steak my sticky fingers over their $1000 precision load...

Really Informative!! Thank You. Hope more other new device clarification

that was really interesting looking in those microwave modules.Thank You for your videos .:)

Very nice presentation, and very interesting. I am not familiar with this topic but you explained it the right way. Thanks a lot and please continue making videos because you know how to make them very useful.

Physics experiments, THz imaging (in airports) and spectroscopy are a few that spring to mind.

Hi Shahriar, great introduction into microwave components. Way beyond my understanding but nice to have an explanation I can understand. Gerry

Thanks for the explanation, that's really informative

That.. Was..AWESOME!!!

Incredibly informative and definitely learnt a great deal from watching this video. You are a wealth of knowledge and greatly appreciate you taking the time to share this invaluable insight. Should've been my professor when I did my EE :). Frankly, addictive watching your videos. Keep up the great work, and will nominate you for Noble prize, cheers!

Another stellar video. I learned a lot. My experience and education is pretty much limited to freq below 1GHz. Higher RF is a bit of a mystery to me. I wish more people would discover your videos.

you are my hero. bro. let me take a seat and watch the tutorials.

It's cool... When you know...you know...Thanks for honest information & Great video.

I have worked with waveguides in the Navy, but never made measurements. Make sense seeing as how I would have been sent to mast if I broke one of those meters. Awesome video.

Excellent Video, Really appreciate your efforts showing these expensive components. Keep it up 👍. I learned alot.. 😊

Love the videos, keep up the good work.

Thank you for the explanation

Very nice and helpful, thank you!!!!

Wondeful Lecture!

a couple of Gigs is almost DC these days. Love the vids, looking forward to see where you are going with RF topic.

As long as you are careful, patient and familiar with the components, everything will be Ok!

Amazing, thank you!

The more varied tutorials there are the better, they will compliment each other. Some one might cover some points while another tutorial will cover another aspect. That's why there are hundreds of books covering each topic, otherwise we would have a single book for each topic. :-)

This was very interesting to watch. I didn't really realize that simple adapters and connectors could make this much of a difference in terms of attenuation and frequency response, but I have personally seen those differences now. Some cables and connector types simply block the signal entirely, whereas others introduce lots of spikes etc. I will prove this in videos very soon (not on this account), unless Shahriar brings a 65GHz VNA home to make another killer video haha. ;) ;)

Really great video.

26:00 Did you ever happen to put together that tutorial on microwave design? You would do a fantastic job and I hope to see that video in the future

👍🏻🇺🇸🇦🇲👍🏻. THANK YOU Shahriar ! Yet ANOTHER OUTSTANDING VIDEO !! I honestly think that I’ve obtained more practical information from this UKposts channel than EE schooling and 30+ years in the field designing, installing and servicing public-safety communications systems. (and tuition was wayyyy cheaper compared to the new “WOKE” Institutions of Debatable 🤪 Learning rates are) Between TSP and IMSAI Guy (& a few others), UKposts is a phenomenal resource that I really could have benefited from in years past. Keep up the great work. &. 73 from an NJ Armo 😷😀

Hi,thank you for the video. Could you explain more on the tapered grounding of the frequency doubler? Thank you.

This was super useful, but I'm sure many of us are wondering how much this stuff costs, so I made notes throughout and looked up prices for everything I could identify. If no manufacturer specified, it's HP/Agilent/Keysight, and prices are either new, or taken from eBay in Jan 2021, all in US dollars. I'm not an expert on any of this, I just looked stuff up. @14:20 - 8710-1765 Torque Wrench, 8 lb-in, $300 (eBay) @17:29 - N5520B, 1.85mm - 1.85mm F-F coupler, DC-67GHz, instrument grade, $1649 @20:14 - 85138A terminator, DC-50GHz, metrology grade, $1036 @21:28 - 33340C fixed 20dB attenuator, DC-26.5 GHz. (obsolete) 8493C replacement part for 33340C, $506 @22:29 - 11636B power divider, DC-26.5 GHz, $1725 @24:46 - 11667C power splitter, DC-50GHz, $2572 @27:16 - 87304C Hybrid Power Divider, 2-26.5Ghz $1144 @28:10 - MACOM 180deg stripline hybrid, $2483 @28:57 - 5086-7518 50 GHz directional coupler, $1400 (eBay) @29:23 - MACOM 3020-4099-00 directional coupler, $75 (eBay) @31:20 - 5086-7489 50 ohm R-Channel coupler, $575 (eBay) @32:17 - Picosecond Pulse Labs 5500A DC Block, $199 (eBay) @33:05 - Picosecond Pulse Labs 5575A 12GHz bias tee, $250 (eBay) @37:32 - SHF 123B bias tee @39:54 - 11612B Bias Network, 45MHz - 50GHz, $2033 @40:32 - MACOM PS20-0001-K DC-30GHz phase shifter @41:51 - Maury Microwave 1819C trible-stub tuner 2-18GHz @44:20 - Marki Microwave D0265IJVV passive doubler @46:33 - Anaren 74125 1-4GHz double balanced mixer, $60 (eBay) @48:23 - Mini-Circuits ZFJ-1000VH amplifier, $100 (eBay) @49:40 - Anritsu A7HB3102 wideband amplifier, $400 (eBay) @50:40 - W281C waveguide adapter, 75-110GHz, $4144 @51:45 - Hitachi WR28(?) directional coupler waveguide, $150 (eBay) @52:26 - millitech 45168H-1000 circulator, CF 140 GHz @53:23 - WR10 horn antenna, $775 (eBay) @54:26 - Cascade 167-A-GSG-100 probe @57:40 - GGB PicoProbe MCW-23-137205

These connectors are precision components. But the main reason they are expensive is volume. An Intel processor is more expensive to produce in small quantities, but you can buy them at a lower price than these connectors because they manufacture millions of them. The price of >50GHz components have already dropped significantly in the past decade.

Ah, you show some basics. Hope for more...

Truly amazing and there was me searching around for a 1GHz Dc block. Thanks for taking your time to make interesting videos. I can only guess why satellites cost so much.

I love this tiny +300 GHz horn hahaha lovely!

Awesome!

Subscribed thanks to this video

The geometry is almost identical. But the coupling will depends on the launch port (i.e. the input signal propagation direction).

SMA in amateur radio handhelds too. Of course for good stuff at 70cm and above you use N connectors.

You want your coupler to be directional because these are mostly used in networks and you want to see where in your network the signal is getting through and not getting through and which direction the signal is coming from, so there fore you can trace where in your network there may be a problem. The signal coming in through the out put port is usually terminated through the coupling to a terminator, unless of course your using a dual directional coupler.

Thank you very much for the awesome content. Do you possibly sell some of those? For example the directional bridge.

excellent educational video.can you give more detailed analysis of phase noise when you can

One minor point... The two step Wilkinson splitter shown at 26:05 probably only works over 700MHz-1500MHz and not 100MHz to 1500MHz. I don't think you can get 15:1 bandwidth from a 2 stage splitter like this.

You can buy surplus waveguide components quite cheaply (about $150-400) but it's when you have to couple back to coax where it gets really expensive...

Small thing - you should only tighten with the torque wrench until its starts to move. If it 'snaps' over you may well put extra torque on the connector.

do you have a list of your tutorials in order they should be watched?

That is actually what that is... I'll look into fixing it.

Amazing, if I may ask, how do you have access to such expensive hardware?

Absolutely superb video, I learnt huge amount. I find RF fascinating nowadays and I wish I could remember more from the comms lectures at university.... Off-topic and random, has any said you sound a bit like the character Dr Nick off the Simpsons? :)

Yes, I did! Those connectors have already been misused and are quiet old.

Man, I wanted to make a video like that! Well, I guess I was too slow. Now I gotta come up with something better. Good job!

Very nice to see some of this stuff, I've *heard* of most of the components on display, but never seen them, let alone with their clothes off ;) What causes the directional coupler to be directional, and why do the forward and reverse ports select power going that direction, the geometery seems nearly identical?

Shahriyar Jaan, You know what would be good is step by step VNA measurement of S11/S21 with calibration OSL. I know how to do it, but I haven't seen any videos on youtube. So it would be the first and very popular. Also how to measure balanced components or antennas with a 2 port VNA, which is a tricky process. Love your work. Mersi ;)

Great video I wish you had detailed schematics draw for better understanding thanks

I did my BSc in EEE and ya i have microwave in my theory and lab....didnt learn this stuff there.learned abt waveguide and radiation pattern of antenna mostly. what do you think teachers should teach in undergrad level microwave lab which is very helpful in the industry?

Question: When using right angle connectors, will there be reflections and return losses? Do they have same performance as inline connectors?

The electronics engineer of the future would do well to take a class in plumbing/ mechanical engineering, with these pipes and cavities. I believe at these GHz freq's the signals/current travel on the surface of the metals due to skin effect. Very interesting video.

Can you please clarify what you mean by "MOSFET" RLC? Are you talking about a tutorial on MOS based VCOs that use LC tanks?

Do you account for the capacitance between the tips of the probes you showed at the end? I would imagine it would be significant at high frequencies.

Hello, maybe you could demonstrate some basic fundamentals of using a VNA by using the Diligent Analog Discovery's basic network analyzer function. You could design your examples to fall within its limited 10MHz bandwidth. Many EE students have this $99.00 device and they would be able to follow along with your demonstration. In the video you could also point out the benefits of using a lab grade VNA too so their advantages would be fully appreciated. Just a thought. Keep up the good work.

Epic popcorn time!! :D

26:10 >tutorial on microwave design wait wait wait, where's that? that's exactly what i was looking for.

good video

At 32:00 the coupler looks very much like the one in HP VNAs such as the 8753 d/e/es series. The resistors on the right hand side have a tendency to burn out due to ESD as they're built onto the trace/board. They can be fixed (basically) by replacing them with a 265 ohm resistor to make up for the burnt out component. Extremely common problem with HP VNAs. The screw positions appear to align and the internal structure is extremely similar, so if this isn't an HP part, it's a knock-off.

I'd love to do a full VNA measurement tutorial, but I would need a VNA for that. :) If someone wants to donate a portable VNA to The Signal Path Blog, let me know!

Thumbs up!

EXCELLENT VIDEO......I WILL SUBSRCIBE

I have to ask. What was the 325GHz waveguide for? What have you used it for in the past? I can't even fathom an application that requires a frequency that high. Wow.

ha I don't know that. thank. Whivh is the maximum frequency use today? among the tera hertz?

Inspection under a microscope is critical. Some metrology labs have bizarre criteria for acceptance of these connectors. For example, I've had calibration kits returned as "okay" when upon inspection, most of the spring fingers inside the connector were missing! It turns out, the only criterion for acceptance was pin depth!

Did you put together a metrology grade connector with an instrument grade cable in the first half of the video? I thought that was bad.

Don't they use solid gold or silver center pins in some of those connectors?

Microwave, the progression of electronics.... to plumbing.

Cool. What ever happened to "plumbing"? Seems that was all one used to see for even moderately high frequencies. Now, it's copper to >100GHz! Can't remember the last time I saw plumbing...

could anyone give some introduction of phase shifter for millimeter wave?

At the end of your video you said that the probe was rated to 40 GHz, but you didn’t describe how impedance could physically work with such a dynamic system. :( Also, now that you have access to a decent/fancy X-ray imager, it would be fascinating to see the actual RF traces that you’ve glossed over throughout your videos 🙏

Your latest video is so pornographic it should not be legal. By far the most interesting part of my day. Thanks! Again!

Can you provide a link to the “connector types” document?

Thanks for showing me all that black Magic. I don't even begin to understand this!

Its really iseful

Pornographic goodness, loved the video! I think Dan is a classic case of the Dunning-Kruger Effect at work. I may even have encountered him before on another website forum. Someone who thinks a 5lb mallet is the appropriate tool for every occasion!

Why the freq ways end at 18GHz, 26.5, 40, 53 etc?

if it's so critical to connect the right type of connector why there are no clear markings on them? if it's not possible to make a different shape I'm sure there could be some text or markings without changing the characteristics of the connector

and you should ti use a63ghz oscilloscope why on that frequency you don't use a spectrum analyzer?

That HP bias network sells for about $950 on Ebay...

👍👍

Can i salvage a (old, defunct) spectrum analyzer and get these components for free? If not, please explain why. Thank you

But how you make this higher frequency? On agilent site I've see signal generator up 63ghz and scope. How you can make this higher frequence? There are some Spectrum analyzer to go up to 1THz what ridicolous way you should use to carrying this frequency?