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--- user:kurser:ham_vt2023_l7 [2023/04/22 18:30] – Added segment on antenna gain and efficiency. user
+++ user:kurser:ham_vt2023_l7 [2023/04/22 19:08] – Added p.e.p. and e.i.r.p. example exam questions on directivity. user
@@ Line 142: / Line 142: @@
 It is thus useful to discuss a real antenna in terms of its gain, rather than in terms of its theoretical directivity.
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+==Emitted power: p.e.p. and e.i.r.p==
+The HAM radio band plan sets radiation emission limits in terms of power, either as **p.e.p.** or **e.i.r.p.** (peak emitted power, equivalent isotropic radiated power).
+  * The p.e.p. limit defines how much peak power may be fed into your antenna.
+  * The e.i.r.p. limit takes antenna gain into account as well, meaning that no lobe may peak above a certain power.
+\\
+//**POSSIBLE EXAM QUESTION**//
+\\
+In the 5.3515-5.3665 MHz band, a HAM radio operator may at most transmit with 15 W e.i.r.p. Are you allowed to transmit at 5.36 MHz with 10 W using a +3 dB gain directional antenna?
+\\
+\\
+Answer: No, this is not allowed. An antenna with +3 dB gain, would make a 10 W radiated emission seem as if we're transmitting with 20 W, which is above the e.i.r.p. limit.
+\\
+//**POSSIBLE EXAM QUESTION**//
+\\
+In the 1850-1900 kHz band, a HAM radio operator may at most transmit with 10 W p.e.p. Are you allowed to transmit at 1875 kHz with 10 W using a +20 dB gain directional antenna?
+\\
+\\
+Answer: Yes, this is allowed, since p.e.p. sets the limit of how much power is fed into the antenna, and does not account for directivity.