Note
: Manipulation of the equation to find the missing
item may be needed in any of the following.
The
mathematical notation is being used where two letter
together means multiplied
eg.
P = VI is the same as P = V x I

Equation(s)

To calculate ????

Page
where
equation is discussed

R(total)
= R1 + R2 + R3

To find the total
resistance in series 
Click here 

To find the total
resistance in parallel 
Click here 
P = VI, V = IR

To calculate
power, voltage, current, or resistance given any other
two. These have
been seen in the Foundation or Intermediate level
courses 
Click here 

To calculate the
voltage_{out} relative to the voltage_{in }with
regards to a potential divider where R_{1} and
R_{2} represent the resistance value either
side of the centre. 
Click here 
P = V^{2 }/
R, P = I^{2}R

As above but this
set are new to the Advanced level. 
Click here


To calculate the RMS of a voltage which gives the
same heating effect as a direct current of the same
numeric value. 
Click here


To calculate the
effective total capacitance of a number capacitors
linked in series 
Click here 

To calculate the
effective total capacitance of capacitors linked in
parallel, 
Click here 

To
calculate the value of a capacitor from area and
separation of the plates, permittivity of
dielectrics 
Click here


To calculate the
effective total inductance of a number inductors
linked in series 
Click here


To calculate the
effective total inductance of a number inductors
linked in parallel 
Click here 

To
calculate the inductive reactance for a known
frequency and known inductance. 
Click here 

To
calculate the impedance from a combination of
resistance and reactance. 
Click here 

The supply voltage
Vtotal (VT) is thus the sum of the vectors through the
Resistor VR and Capacitor VC (or Inductor) 
Click here 

To
calculate the capacitive reactance for a known
frequency and known capacitance. 
Click here 

To calculate the
frequency of resonant a tuned circuit knowing the
value of the inductance and capacitance. 
Click here 
T
= 1 / f and f = 1 / T

To calculate the
time period of a sine wave at a particular frequency
or the frequency knowing the time period. 
Click here

T=CR

To
calculate the charging and discharging of a
capacitor in a CR circuit 
Click here

and

To calculate the Q
factor ( quality Factor) knowing the value of the
frequency, inductance and capacitance. 
Click here


Calculation of the
Q of a tuned circuit, knowing the centre frequency,
and the upper and lower frequencies where the half
power points are noted. 
Click here 

To calculate the dynamic resistance R_{D}
knowing the value of the resistance, inductance and
capacitance 
Click here 

The relationship
between Q and Frequency, Capacitance, and Dynamic
Resistance 
Click here 

Formulas relating transformer primary N_{p}
and secondary N_{s }turns to primary and
secondary potential differences V_{s} V_{p
}and currents I_{p} I_{s} 
Click here 


Formula
relating transformer primary N_{p} and
secondary N_{s} turns to primary and
secondary impedances Z_{p} Z_{s} 
Click here


The two equation
mean the same hfe = and is used to calculate the gain of
a transistor. 
Click here 

To calculate the
frequency step from the crystal frequency. 
Click here 

To calculate the
out going frequency from a frequency synthesizer. 
Click here 
c
= 3 x 10^{8} m/s

speed of light But
this might be better remembered as
c = 300 x 10^{6}
m/s

Click here 

The
equations relating to decibel power ratios. 
Click here 

The
calculation of standing wave ratio (SWR) by
reference to V_{FORWARD }and V_{REVERSE}

Click here 
v
= f
c
= f
Please
note that sometimes v is used for the speed of light
and at other times c.

From the speed of
the velocity of light the wavelength can be determined
knowing the frequency or the frequency knowing the
wavelength. This was first introduced to you in chart
form in the Foundation Licence course. 
Click here 

The
equations relating to decibel and voltage ratios. 
Click here 
Z_{0}^{2}
= Z_{in} X_{ }Z_{out }

The formula
relating Z_{0} = the impedance of the
quarterwave length of feeder matching line to the
impedance of the antenna Z_{in} and the
impedance of the antenna Z_{out} from the
matching line 
Click here 

To
calculate the field strength in volts /m given the
ERP and distance from the antenna. 
Click here 

To calculate
return loss 
Click here 

Bw is the
bandwidth requirement in relation to Af is the highest
modulating frequency and Δf is the carrier peak
deviation frequency 
Click here 
erp = power x gain (linear)

To calculate the
Effective Radiated Power (erp) from an antenna 
Used in the Intermediate course 

To calculate gain
of Yagi over a dipole 
Click here 
