The Signal Path I like that you began playing with electronics at 10 years old. I did the same. I've been an engineer for 45 years. I'm 66 years old and still learning. The more I know, the more I realize that I don't know.

Dear Professor Shahriar, I want to build a system where I can monitor all radio frequencies at once, within the 10-20 mile radius? Is there a way a hobbyist can do that with say dozens of SDR USB Dongles and a few Raspberry PI3s? Self-financing has that "being poor" side-effect. I have already made the most sensitive 3D Geiger counter possible with SI-22G tubes. Also a Light spectrometer using plans from the internet (public Labs). They work great. I am currently working on computerizing my 6" Newtonian telescope, and attaching one color and one IR RPI cameras, green 500mW laser pointer, Spectrometer,... to be attached to the body of the telescope. So, when I aim at an object with the laser, I would see it in both cameras, the telescope, and the spectrometer. The Chilean and US Navy videos on those UFOs, has proven to me they exist and gathering scientific data, is the only way to go towards figuring out what these things are, and how they work. Can you provide some guidance as to the easiest/cheapest way for a technologist to detect and record local EM anomalies to be studied later? Merci. Khoda Hafez.

@@ufohunter3688 By all radio frequencies at once, what are the frequency range you are talking about?

Could you make a tutorial explaining the basic elements of a RF digital transceiver such as a Bluetooth or WiFi modem?

@@billmoran3812 Its nice to hear that someone so experienced keeps learning. I only really started messing around with electronics about 2.5 years into my degree (I would have been about 24 around that time) and was sort of angry at being so lost - I thought I should be able to understand it all since I'd been studying it all in uni. Lately though, I'm starting to appreciate that this stuff can be really hard, and that there is no substitute for spending a lot of time, reading, watching, doing, making mistakes and learning. Hope to be a lot better at this stuff one day! Electronics is awesome.

Agreed. The clip repeats twice!

I finally understand why Re, Ce, and Cc are needed (most just hand wave this part) Thanks for the clear explanation.

You are welcome.

That seems like quite a late time to teach this?

@@zetaconvex1987 we study it in the second year but our bachelor degree is only 3 years

Due to availability, I would have to make the 1st stage amplifier with following component values: BC 547, Rc=Re=1k, RB1=14k, RB2=10k, Cc=0.1uF, Cb=Ce=100uF Will the amplification calculation (i.e. A=-64) and the practical results (i.e. Vin=5Vpp, Zin=50, f=2.5kHz, Vout=300mVpp) hold (under experimental error allowations)?

Some people can hear below 20Hz and spectral content above 20kHz also plays a role in signal shape at far lower frequencies, we always designed for 5Hz-100kHz, but with EQ on the passband gain. RIAA is a good starting point, most people prefer a smiley face curve : ) so shelving filters are good for the general public. You’re correct, design for flat response across the range will sound terrible to most people even though it’s technically perfect...

I also find that explanation a little lacking, more after having been watching other videos searching for a more in-depth answer on why are Rc and Re chosen as they are, and finding conflicting answers. Absolutely think this video is gold, no intention to devalue it a bit. Thanks Shahriar!!

It's because of the values. High capacitance values are just available for electrolyte cap types or for tantalo types. The electrolyte ones are less expensive and easily available. Hello from Brazil!!