NSH Field Strength Meter

Posted on Feb 6, 2014

A well tuned antenna system works like a dummy load, i. e. the SWR is 1. 2:1 or below but the hunting range is low. What`s wrong Insufficient radiation How to know that Yes, this is what the article about. You can measure the effective radiation using a field strength meter (FSM). A commercial FSM can measure the loss or gain of radiation, testin

NSH Field Strength Meter
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g polarisation, plot the radiation pattern for the various antennas for comparison. The cost for a commercial FSM can vary from Rs 1500/- to Rs 5000. But this design one can assemble for a few hundred. The Standard Analog Meters or LCD - DVM based FSM are some what DEAF  and the meter level movement can`t be read from a distance of around 5 ft and above. To avoid this problem, this FSM is having a 10 level multi coloured 3mm LEDs for level reading; this will give a fair reading up to 20 ft + distance even at night. The FSM will give RF radiation reading; picked through the air, that shows an antenna`s gain of radiation. Due to this REAL READING, one can compare different types of antennas gain, angle of radiation, polarization etc. The FSM sniffs out bad coax, connectors or improperly grounded transmitter. It is a good instrument to plot radiation patterns of yagis / verticals. It is an educational tool for studies. SWR meter cannot do or detect some measurements about RF. But this FSM will do!. When Working with different types of input RF signal levels, the sensitivity of the NSH FSM can be controlled by changing different types of sensing antennas. Remember that, VSWR meter only shows that the antenna is fully loading and shows a low reflected power or very low SWR, but it does not mean that the antenna is efficiently radiating the TX power into AIR - The only tool that shows the exact on-air radiation levels is FSM....

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