Questionable DRO LNB teardown & test (INVERTO RED Classic Single straight 40mm)
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- čas přidán 11. 09. 2024
- Taking a look inside a cheap DRO LNB, and experiencing first-hand why they aren't used anymore.
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My website and other social media - sgcderek.githu...
8:52 Did you just call me nobody? 🧐😂Good idea though, there seems to be little to no "entry level" information and particularly nothing useful on YT. I'll put it on my list. 12:24 The Diameter of a Dielectric Resonator is roughly the speed of light divided by [the desired frequency times the square root of the relative permittivity of the material used]. The material is usually some barium and titanium oxide. At the resonance frequency, the electric field moves in circles inside the resonator, like being stuck in a roundabout. This is called the TE01δ (say: TE 01 delta) mode. The little striplines next to it are used to couple some of the oscillator's signal into the "roundabout" and the other stripline is used to couple some of the signal in the roundabout back into the amplifier, thus closing the loop (and fullfilling the Barkhausen stability criterion). The dielectric resonator is usually positioned 1/4th of a wavelength away from the end of a microstripline as the E-field has a maximum peak there. If you see one microstripline being longer than the other, one is simply 1/2 wavelength (or multiples of 1/2) longer than 1/4th wavelength. Which changes nothing from an impedance and field strength standpoint, but reduces direct coupling from one microstrip into the other. This roundabout effekt of the TE01δ mode only works at the correct resonance frequency. The reason why they can be tuned with metallic objects, such as screw, is, because there also is a magnetic field influencing the flow of traffic in the roundabout. Changing the permeability by disturbing the H-field will shift the resonance frequency.
Thanks for your video. Saludos desde España
Great Video, Good Luck...🎉
I wish I was smart enough to understand this 😂