1.8 KiB
1.8 KiB
The Full Technician Study Guide
- the unit of frquency is Hz
- Radio is an alternating current
- voltage = current x reistance (E = I x R)
- the number of cycles per second if the frequency
- the unit of resistance is the ohm
- the unit of capacitor is the farad
- what image is usually depicted as a coil of wire = inductor
- the unit of inductance is the henry
- the voltage stays on a capacitor but it does not on an inductor
- the following battery chemistries are rechargeable
- nickel-metal hydride
- lithium ion
- lead acid
- the following bettery chemistry is not rechargeable
- carbon zince
- Rapid flutter on mobile signals due to multipath propagation is called picket fencing
sidenote: A Zener diode is a special type of diode designed to reliably allow current to flow "backwards" when a certain set reverse voltage, known as the Zener voltage, is reached. Zener diodes are manufactured with a great variety of Zener voltages and some are even variable
- finding tropsopheric duct - https://dxinfocentre.com/tropo_eur.html
Units
G (giga) = 10^9 M (mega) = 10^6 k (kilo) = 10^3
--
m (milli) = .001 10^-1 M (micri) = .000000 19^-6 n (nano) = 0.000000000 10^-9 p (pico) = 10^12
500 mW = 0.5 W 3000 mA = 3 A 3.525 MHz = 3525 kHz 284400 kHz = 28.400 MHz
- Decibels (power ratios):
- 3 dB --> 2:1 (ex. 5W --> 10W)
- 6 dB --> 4:1
- 10 dB --> 10:1
- Decibels are logarithmic
electronic current that allows current to flow in only one direction --> diode
what are the two charges of a diode --> anode + cathode
- Electrolytic capacitor
- transistors can be used as an electronic switch
- can also be used an amplifier
- FET = field effect transistor
- bipolar junction transmitter
- NPN
- PNP