nice Video...i am also fascinated about the RF stuff specially the diplexer it is so critical every single slot every copper piece have to be at the exact position sbsolutly amazing stuff.....for me as an technician...it is a piece of RF art ....
Very interesting! A few things: 11:00 these are not transistors, but gain blocks -- (from how they are powered.) 14:00 The large capacitors present a short to the ground at the high frequency, and they are connected through a transmission line to the drain of the MOSFET. The length of the line is chosen such that the transistor would see a high impedance at the working frequency instead of a short. Ordinarily, this would require a quarter wave line, but here there is more going on with the small capacitor in the middle of the line -- this and the different length/width lines in the middle serve to match the impedance of the transistor to the rest of the circuit. (Same with 15:20 -- quarter wave line is an impedance transformer, which allows to have large capacitors to the ground without them shorting the RF output -- this has nothing to do with filtering the power supply ripple.) 17:00 this is a directional coupler. It is configured to measure the signal reflected from the antenna. If there is a bad impedance mismatch at the output of the unit (bad cable, damaged antenna, etc) the reflected power can destroy the output transistors. This unit most likely shuts them off if the reflected power monitor picks up a signal above certain threshold.
The diplexer looks for me like a Narrow Bandwidth Cavity Filter. You use the screws to adjust the frequency spectrum for each frontend. Those rf filters are very precise so you have very little crosstalk and avoid noise in the receiver from other base stations nearby (or the same tower).
I just took a look at some boards on my work desk for a teardown video that will come out... maybe this year... :) It seems to have 12 layers, not sure if there is copper in-between all of them.
It is unfortunately as loud as it can get, as seen in the brackets [fixed audio], this was a reupload of a previous version where sound was even lower. Sorry about the failure to record the sound properly.
You even talk like a mustache guy, but it looks kida unreal, reminds me of my nephews mustache 😄 But it is not good enough to distract me from the main content, very cool stuff, people who believe in magic, gods and all that stuff, should get into technology, especially in electronics, well, or atleast educate themselves a little.
It's all about impedance matching, the goal is to maximize the power to the processing unit/network of the incoming signals. To explain this in detail requires a whole new video. I recommend googling "RF tuning".
Keywords in this field of expertiese are, but not limited to: stubs, signal reflections, transmission line, impedance matching, and of course the Smith chart.
Totally mind blown by this diplexer stuff! I didn’t know such strangely beautiful hardware exists. Thanks for showing that!
nice Video...i am also fascinated about the RF stuff specially the diplexer
it is so critical every single slot every copper piece have to be at the exact position
sbsolutly amazing stuff.....for me as an technician...it is a piece of RF art ....
Very interesting! A few things: 11:00 these are not transistors, but gain blocks -- (from how they are powered.) 14:00 The large capacitors present a short to the ground at the high frequency, and they are connected through a transmission line to the drain of the MOSFET. The length of the line is chosen such that the transistor would see a high impedance at the working frequency instead of a short. Ordinarily, this would require a quarter wave line, but here there is more going on with the small capacitor in the middle of the line -- this and the different length/width lines in the middle serve to match the impedance of the transistor to the rest of the circuit. (Same with 15:20 -- quarter wave line is an impedance transformer, which allows to have large capacitors to the ground without them shorting the RF output -- this has nothing to do with filtering the power supply ripple.) 17:00 this is a directional coupler. It is configured to measure the signal reflected from the antenna. If there is a bad impedance mismatch at the output of the unit (bad cable, damaged antenna, etc) the reflected power can destroy the output transistors. This unit most likely shuts them off if the reflected power monitor picks up a signal above certain threshold.
Thank you very much for the additional information and corrections. I live to learn :)
@@KaizerPowerElectronicsDk Your videos are great. It is always curious to see how different things are constructed.
Excellent series. Really appreciate it! I believe the RF connectors from board to board are SMP or equivalent.
The diplexer looks for me like a Narrow Bandwidth Cavity Filter. You use the screws to adjust the frequency spectrum for each frontend. Those rf filters are very precise so you have very little crosstalk and avoid noise in the receiver from other base stations nearby (or the same tower).
Nice channel man, subscribed.
This makes tuning a 6th order band pass subwoofer look like childsplay... All those tuned and ported cavities. Black magic indeed.
Excellent job, subscribed.
This is awesome man. How many layers do the boards in these typically have? It would be interesting to see cross sectional views. :)
I just took a look at some boards on my work desk for a teardown video that will come out... maybe this year... :) It seems to have 12 layers, not sure if there is copper in-between all of them.
Ever consider doing a collab with Shahriar from thesignalpath? Maybe you could tease out more of what's going on with the cavity filters together.
I would love to do some videos with him. He has much more equipment to do some actual measurement analysis on these parts.
Thumbnail looks like SNES fantasy RPG
I see it now you mention it!
Legend of Zelda A Link to the Past)
Please make the sound louder!
Very nice video. Thanks!
It is unfortunately as loud as it can get, as seen in the brackets [fixed audio], this was a reupload of a previous version where sound was even lower. Sorry about the failure to record the sound properly.
Great
Ideal conversion to 2.4G SDR Ham radio repeater project.
Da_Stier has made several conversions out of these amplifier modules: highvoltageforum.net/index.php?board=34.0
Fair bit more complicated than SDR based on an RTL dongle...
Where are the backdoors that steal your data or is that done through malicious code
Its most likely done in the backbone of the system, not in frontend systems like this.
You even talk like a mustache guy, but it looks kida unreal, reminds me of my nephews mustache 😄 But it is not good enough to distract me from the main content, very cool stuff, people who believe in magic, gods and all that stuff, should get into technology, especially in electronics, well, or atleast educate themselves a little.
I wish there was someone somewhere who bothered to actually explain the RF black magic that happens in those beautifully carved canyons..
It's all about impedance matching, the goal is to maximize the power to the processing unit/network of the incoming signals. To explain this in detail requires a whole new video. I recommend googling "RF tuning".
Keywords in this field of expertiese are, but not limited to: stubs, signal reflections, transmission line, impedance matching, and of course the Smith chart.
Who writes software for those chips ?
Chinese programmers ;)
typedef Nortel up in Canada before Huawei stole all their software and put them out of business.
@@helloworldstein username checks out
Meget bedre lyd - sådan!
From the thumbnail I thought it was a Pokémon lets play
Where's the spy chip?
In the backbone of the system. Never in the frontend.
CPU board: so it is where all the spying is supposed to happen right? Oh yeah indeed there are so many US chips (TI, Altera, Freescale, PMC) 😉
This is not for spying, but there are secret messages in the via patterns.
They have installed a very tiny microscopic chip which the human eye can't see, trust me. - US Conspiracy Theorist who watches FOX NEWS