Oh great now I have to be a "senior engineer specialist" too!
Love it when a title is used to redefine a job people have been doing for years.
RF design isn't really all that well defined. When PC traces act like transmission lines, and the inductance of the leads on a capacitor create a tuned circuit - anything more than a very, very basic design runs into some fascinating problems.
Really; put a circuit on a PC board that generates a watt or two of clean 100 MHz power into a 50 ohm load. That seems to be simple, but many engineers have tried and failed. It's not impossible, but youthful attitude won't do it. Experience, lots of experience helps. If you can do it, and do it in production - you're a golden boy with a bright future ahead of you.
Those who say this isn't a challenge haven't tried it. Parasitic capacitance and inductance become important circuit elements - and they're completely undefined and seemingly random. If your amplifier oscillates for no apparent reason - that's just part of the learning experience. Higher and lower frequencies seem to be easier, but 100 MHz is just plain damned difficult. Getting a watt or two of clean 100 Mhz sine waves into a 50 ohm load is an achievement.
The industry knowledge was based on mentor ship. Knowledge was passed down from the seniors to the juniors. It worked great. Since the bulk of the knowledge was maintained and improved this way only a small portion has been captured in literature. Now with the generations after mine think thought they know better and did not want to listen to vast knowledge of the seniors. The result is what was common was/is now hard, and what was done before is rediscovered. From what i have seen, the skills is almost back to where the new attitude began. The newest generation of engineers are keen and I am confident the remaining lag will soon be overcome.
On the upside the people that did listen to their seniors always had a job. I was good to be a golden boy, now it is time for the 30 something's to take over.
I chose that example in my challenge for this reason. 100Mhz is right in the FM broadcast band, and a couple watts of clean output is pretty tough to do. You won't find but a handful of engineers who have any experience in this area - and they probably won't talk to you. There's no cookbook designs to speak of - and they'll never mention how critical board layout is - or how to maintain impedances through the output filtering to keep from generating even more harmonic noise and less output.
It's a "prove yourself" kind of challenge. Just like a real job would be - if you're pushing electronic design forward, you won't have access to folks with previous experience. I'm retired now and am endlessly amused by some of the designs that are being created these days. Elsewhere on the forum someone was asking how to drive a piezo transducer to maximum output for rodent control. There were suggestions of using AVR, or a 555 and some amplification. One fellow got close but missed the key. Piezo transistors are resonant devices, and the phase shift across them at resonance is well defined. Use the transducer to provide positive feedback to it's driving transistor and you can get that transducer screaming with 3 or 4 components.
MCUs and digital circuits are very valuable and every good engineer should know about them. But analog circuits are very valuable too; almost every digital device that interfaces with humans or the outside world includes analog circuitry. Resonance is magic, and should be well understood. And it's very, very important to know your components. There are no pure passives; every R includes some L and C. Just like every C includes some R and L, and every L includes some R and C. Those hidden additional components bring many a seemingly great design to its knees. Even your conductors; wires, or the traces on a PC board include R, C and L. Getting a good handle on all of the little details prepares one to turn out designs that work - every time. If you're having mystery problems with a circuit, it's time to go back to the books.
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