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IF_MixerSpurious finds all spurious signals that fall within
a given Intermediate Frequency range(IF).

Given a basic 2 frequency mixer scenario. FIF=(+/-n)FRF+(+/-m)FLO

It can calculate all spurs that fall in the given IF frequency band
for n and m harmonics up to 10th order given the Radio Frequency(RF) and
the Local Oscillator(LO) Frequency.

The complexity of radios and their associated control circuits now
involve many clocks, buses and other frequency signals.
Some or all of these frequencies can leak into the RF and LO paths from
supplies, trace coupling, ground coupling Etc. Also unwanted frequency
mixing can occur in almost any active semiconductor device such as
transistors, logic gates, Integrated circuits.

These unwanted frequencies, their harmonics and mixing products can cause
numerous system problems in radios.


Receiver Spur. Can cause jamming of receiver frequencies from images, Intermodulation.
Quieting Spur. Frequencies that fall exactly on the RF and degrade the sensitivity.
Transmitter Spur. Can cause unwanted frequencies in the transmitter that fail emissions.

IF-MixerSpurious can calculate these spurs for up to seven input frequencies and up to the
10th harmonic order. FIF=aF1+bF2+cF3+dF4+eF5+gF6+hF7

The output format is (a,b,c,d,...) where the order ranges positive and negative. (+/-)a
All frequencies in Megahertz but really unit-less.

Quick Start:
1. Select the number of input frequencies.
2. Enter the frequencies.
3. Enter the IF start and end frequencies or select a "Standard IF" and Bandwidth.
4. Select the maximum harmonic order to search.
5. Press calculate Button.
6. Spurs are displayed in a Gridview Control.
7. Select a spur on the grid and then go to the Details page for complete information.

1. Change the color theme to Light, dark, or your windows default.
2. Clear the stored settings. The inputs on the main page are stored on pressing calculate.
The color theme is saved when selected.

Topic starter Posted : 08/01/2020 11:10 am