Here is a little worksheet that I made for RF Safety
Evaluation. It may look strange on your email
reader because of the longish line length, but save it
to a file, and then you can edit it. It contains sample
data that you can overwrite with your own data.
I Just filled out one of these for every band/antenna and
used the data as input to the University of Texas
Internet RF Safety Calculator. I printed the worksheet and the
UTex output sheet for each band/antenna, put them
in a binder, and the evaluation is done.
Use this worksheet at your own risk. If anyone spots something
wrong in this worksheet or method, please let me know.
Dave Hachadorian, K6LL
K6LL@juno.com
Yuma, AZ
A. Callsign: AA7AAA
B. Frequency, MHz: 21.45
C. Maximum PEP transmitter output, watts: 1500
D. Type of feedline: RG-213
E. Length of feedline, feet: 80
F. Feedline loss, negative dB: -.8
G. Line F divided by 10. (It will be a negative number). -.08
H. PEP power delivered to the antenna: line C antilog line G
1500 ALOG -.08 = 1248
I. Worst case (highest) Emission mode duty factor: .4
FSK, RTTY, AFSK SSB, FM Voice: 1.0
Conversational SSB, heavy speech processing: 0.5
Conversational CW: 0.4
Conversational SSB, no speech processing: 0.2
J. Transmit/Receive duty cycle over six minutes: .5
Longest conceivable percent transmit time in six minutes,
expressed as a decimal.
K. Transmit/Receive duty cycle over 30 minutes: .5
Longest conceivable percent transmit time in thirty
minutes,
expressed as a decimal.
L. AVERAGE power to antenna, controlled case: H x I x J = 250
M. AVERAGE power to antenna, uncontrolled case: H x I x K = 250
N. Antenna Gain, dBi: 9.5
O. Closest CONTROLLED human proximity to antenna, feet: 46
P. Closest UNCONTROLLED human proximity to antenna, feet: 51
Proceed to the University of Texas World Wide Web Site:
http://www.cs.texas.edu/users/kharker/rfsafety
Input items L, N, O, B (controlled case). Print the output sheet.
Input items M, N, P, B (uncontrolled case). Print the output
sheet
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