Freightclasscalc.com accepts no liabilty for any inaccurate class estimates.

Al gathers all of the papers containing these calculations (along with his notes) and files them with his station records.

The tower is located 40 feet from the house, and solving for the hypotenuse of the distance between his residence and the tower (his one-floor house has the top of the first floor 12 feet above ground), he calculates that the antenna is located 43.9 feet from areas of controlled exposure. If transmitting antennas of directional gain greater than 6 dBi are used, both the maximum conducted output power and the maximum power spectral density shall be reduced by the amount of dB that the directional gain of the antenna exceeds 6 dBi. On 10 meters, he is using a 3-element Yagi 30 feet in the air.

It is useful to carefully write out whatever values are being worked with, including units, and perform dimensional analysis to ensure that the final result has units of Below is a table of units in which density is commonly expressed, as well as the densities of some common materials. The FCC has determined that any transmitter that operates at an exposure level greater than 5% of the power density permitted to its own operation is jointly responsible with all the other operators within its exposure area who are also exceeding 5% for site compliance. The calculation of density is quite straightforward. Rounding his gain up to 9 dBi, he determines that his antenna needs to be 50.6 feet from controlled exposure and 113.2 feet from uncontrolled exposure. Radiated Power Calculator: ERP, EIRP, dBuV/m, dBm & mW This RF calculator has been developed by Compliance Engineering to correlate between EMC measurements on RF transmitters, RF receivers and RF Transceivers and related limits detailed in EMC compliance standards. This free density calculator determines any of the three variables in the density equation given the other two. If the In addition, the maximum power spectral density shall not exceed 17 dBm in any 1 megahertz band. This antenna is at the top of his 45 foot tower, so he can run continuous power on 2 meters. This RF calculator has been developed by Compliance Engineering to convert between the various radiated RF field units that are referenced in EMC standards.


There are many different ways to express density, and not using or converting into the proper units will result in an incorrect value. Exhibit D – Power Density Calculations Page 2 of 8 Power Density (dBW/4 kHz) = P (dBW) + 36.0 dB-Hz - 10 log B + PF, where P = per-carrier input power (to the antenna) 36.0 dB-Hz is a factor to convert power density from a 1 Hz bandwidth to a 4 kHz bandwidth .

FCC Maintains Current RF Safety Rules: On November 27, 2019, ... FM Model Calculator FM Model, a program created by Commission staff, is based on a model originally developed by the EPA, to predict ground-level RF power density in the vicinity of towers supporting FM radio broadcast antennas. In addition, explore hundreds of other calculators including topics such as finance, math, health, fitness, weather, and even transportation. The evaluation exemption for amateur repeater operation is determined by the All amateur repeaters using 500 W ERP or less generally do not need to be evaluated. Rounding up to 9 dBi, he determines that at 100 W his antenna needs to be 13.2 feet from controlled exposure and 29.5 feet from uncontrolled.

Please provide any two values to the fields below to calculate the third value in the density equation of The density of a material, typically denoted using the Greek symbol ρ, is defined as its mass per unit volume. This does not pass for full power, but passes easily when he calculates his average power. Within 20 minutes he has completed his station evaluation!There is a little wrinkle in the rules when it comes to repeaters. 2 meters, 35 W FM, 100 W CW and SSB 60 feet above ground.He could calculate his average power for the remaining operation, but this may not be necessary. * This is an esitmate only as the density is the main factor for determination of class but some other factors can effect it such as value of freight, oversize, special loading/unloading requirements, perishability, etc.

Radio EMC standards may reference radiated RF power limits for ERP or EIRP in terms of… )The calculations used to create the far-field tables have been written into BASIC by Wayne Overbeck,N6NB. C. The combined RF exposure for the operators (and visitors) can then be determined by totaling these percentages for all transmitters. Those that operate with more than 500 W ERP need to be evaluated if they have an antenna mounted on a building, or if any part of a nonbuilding-mounted antenna is less than 10 meters (32.8 feet) above ground. Field Strength Calculator: V/m, dBuV/m, dBuA/m, pT, dBpT, Tesla, Gauss, A/m, mW/cm^2 & W/m^2.

Al first tries his evaluation with PEP, using On 40 meters at 1000 W, Al first rounds his dipole gain up to 3 dBi. However, it is important to pay special attention to the units used for density calculations.
The tower is 50 feet from the property line, for a total distance of 55.5 feet from ground level exposure On 2 meters, his antenna has 8 dBi of gain. Calculator POWER DENSITY option can be used to calculate the percent of MPE contributed by that transmitter at the location used by the operators (and possibly visited by the public). This software has been written into a Brian Beezley, K6STI, has made a scaled-down version of his FCC RF-Exposure Regulations -- the Station Evaluation (This is another example that higher antennas generally create less field strength on the ground than lower antennas!