This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
Gain describes how an antenna concentrates energy. dBi compares that with an imaginary isotropic antenna. Beamwidth is the angle where the energy is still useful. The calculators convert units and estimate a width from numbers you type. They do not transmit.
A higher gain is a narrower beam, not a free increase in power. Regulatory limits still apply to the power you radiate. One radio on a site you administer, or a documentation example. Do not point a link at a network you do not run.
Coax loss and wavelength belong in the same note if you are budgeting a link. The survey itself is a later page.
The change you can finish
Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.
Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.
- Name the antenna or label the example.
- Convert the gain.
- Write the beamwidth.
- Note the regulatory cap.
- Do not transmit as a test.
- Stop.
Mistakes that outlive the command
Antennas Explained: Gain, dBi and Beamwidth goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Gain treated as extra legal power.
- A beam aimed at a site you do not administer.
- Transmitting to see.
- dBi and dBd mixed with no conversion.
Decisions to write down
One decision for Antennas Explained: Gain, dBi and Beamwidth: The radio is yours or an example. Gain and beamwidth are both written. The power cap is noted. Nothing was transmitted. And units were converted.
Checks before you call it done
Confirm this before you call the change done: The gain is written. The beamwidth is written. The unit is written. No transmission was started. And the site is yours or labeled. If one of those fails, stop.
Before you leave the device
Antennas Explained: Gain, dBi and Beamwidth ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.
0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.
One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature waits for its own page.
If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied config produces a device nobody can rebuild. Restore the copy you took first.
A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.
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