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@kanchudeep
Last active December 24, 2018 06:32
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Antenna Length:
1/4th length [in m] = 74948114.5 / f [frequency in Hz]
1/4th length [in cm] = 7494.81145 / f [frequency in MHz]
Radio Frequency Spectrum Ranges:
VLF: 3kHz-30kHz 100Km-10Km
LF: 30kHz-300kHz 10Km-1Km
MF: 300kHz-3MHz 1Km-100m
HF: 3MHz-30MHz 100m-10m
VHF: 30MHz-300MHz 10m-1m
UHF: 300MHz-3GHz 1m-10cm L (1-2GHz), S (2-4GHz) band
SHF: 3GHz-30GHz 10cm-1cm S (2-4GHz), C (4-8GHz), X (8-12GHz), Ku (12-18GHz),
K (18-27GHz), Ka (27-40GHz) bands
EHF: 30GHz-300GHz 1cm-1mm Ka (27-40GHz), V (40-75GHz), W (75-110GHz),
mm (110-300GHz) bands
* Microwave: 1GHz+
* Millimeterwave: 30GHz+
* Long Wave: 148.5-283.5kHz?
* Medium Wave: 525kHz-1,705kHz (10kHz spacing)
* Short Wave: 1.6-30MHz
* FM: 88MHz-108MHz
Usage:
• ADS-B (Automatic Dependent Surveillance - Broadcast)
1,090MHz
978Mhz (for aircraft exclusively below 18,000'/5,486m in USA)
• AIS (Automatic Identification System): 161.975MHz & 162.025MHz
• CB radio: around 27MHz
• IRNSS/NavIC: L5 (1,176.45MHz) and S band (2,492.028MHz)
• GPS: L1 (1,575.42MHz), L2 (1,227.60MHz)
• GLONASS: L1 (1,602+[9/16]MHz), L2 (1,246+[7/16]MHz)
• HAM/amateur band: 144-14MHz Narrow FM
• Marine emergency communication: 2,182kHz
• VHF universal use:
50-54MHz: Amateur Radio 6m band
108-1,18MHz: Air navigation beacons VOR and Instrument Landing System
localizer
118-1,37MHz: ATC (AM), 121.5MHz is emergency frequency (HF/UHF)
144-1,48MHz: Amateur Radio 2m band.
• Weather Satellites
Meteor M1: EOL
Meteor M2: 137.9MHz
NOAA 15: 137.62MHz
NOAA 18: 137.9125MHz
NOAA 19: 137.1MHz
Convert dBi to dBd
Subtract 2.15 from dBi rating to get equivalent dBd rating.
* 'i' means it is a measurement relative to an isotropic antenna and 'd'
means it is a measurement relative to a dipole antenna. Dipoles have a 2.15dB
gain compared to an isotropic antenna.
Devices:
• Elonics E4000:
52-2200MHz (gap approx 1100-1250MHz)
Approx 50MHz-2.3GHz (possible when used out-of-spec, with gap)
• NooElec NESDR SMArt
RTL2832U interface IC
R820T2 tuner IC
0.5PPM TCXO
25MHz-1750MHz
2.4MHz bandwidth
Female SMA
• RTL-SDR Blog v3
RTL2832U interface IC
R820T2 tuner IC
1PPM TCXO
Bias-tee
500kHz-1,766MHz (500kHz-24MHz in direct sampling mode)
2.4MHz bandwidth
Female SMA
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