Electronic Terms and Glossary

For a list of Electronic Terms and Glossary, click Glossary.

Watts <> dBm <> Volts Converter

This calculator converts between watts, dBm, volts and dBmV.

Select the Impedance then enter any one of the other parameters below and the rest will be calculated automatically

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RF values:

dBm	mW	Notes
0	1	Exact by definition of dBm
3	2	3 dBm is actually 1.995 mW but that's near enough for most practical purposes
10	10	Exact
+3	X 2	Adding 3 to the power in dBm is the same as multiplying the power in Watts by two (actually 1.995 but that's near enough for most practical purposes)
+10	X 10	Adding 10 the the power in dBm is exactly the same as multiplying the power in Watts by 10

Voltage Divider Resistance Calculator

Enter any of the three values and then click the Calculate button.

V_in = Input voltage
V_out = Output voltage

Yagi Antenna Calculator

Note : These results are optimised for gain. However, if the parasitics differ much from 0.4 ±0.05 * λ or the gain is larger than 16 dBd you should become distrustful.

Dipole Antenna Calculator

Impedance (Ω):	50Ω	Common in RF and Microwave Systems
	75Ω	Common in TV and Video Systems
	600Ω	Common in Audio Systems
		Custom Value

milli Watts (mW):
Watts (W):

dBm:
dBW:

V_RMS:
V_Peak:		Assuming a sine wave
V_P-P:		Assuming a sine wave

dBmV:		dB relative to 1mV RMS. Often used in the cable TV industry and only valid in 75Ω systems

Freq. [MHz]
Boomlength [m]
Gain [dBd] (approx.)
Elements
Diameter of parasitic Elements [mm]
Diameter of Boom [mm]
Is the boom isolated from parasitics ?	yes no

Frequency	MHz
Halfwave (L)	m	ft
Quarterwave (E)	m	ft

REQUIREMENTS

Freq. [MHz]

Boomlength [m]

Gain [dBd] (approx.)

Elements

Diameter of parasitic Elements [mm]

Diameter of Boom [mm]

Is the boom isolated from parasitics ?

yes no

DESIGN DATA FOR YOUR YAGI

Note : These results are optimised for gain. However, if the parasitics differ much from 0.4 ±0.05 * λ or the gain is larger than 16 dBd you should become distrustful.