From c20f5d5c51276012c78c81166636e84ef8cb40aa Mon Sep 17 00:00:00 2001 From: sh123 Date: Wed, 17 Jun 2020 22:45:13 +0300 Subject: [PATCH] Update README.md --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index b1d193f..ed1c864 100644 --- a/README.md +++ b/README.md @@ -64,7 +64,7 @@ All work was done on ESP32-WROOM with custom made LoRa shield, if your ESP32 boa - Antennas - Client: rubber duck, halo, mobile antenna on a car roof - Server: 7 element UHF yagi indoors, vertical on the roof - - With such low power it is very important to have antenna SWR close to 1, many rubber duck antennas are claimed to be 433MHz, but they do not resonate at that frequency at all or resonate only when attached to its native large handheld transceiver, which has enough metal inside to behave like a counterpoise, these antennas have SWR 2 or higher. Check your antenna on antenna analyzer before using, add counterpoise if needed or better to use dipole or halo home made antenna for that matter + - With such low power it is very important to have antenna SWR close to 1, many rubber duck antennas are claimed to be 433MHz, but they do not resonate at that frequency at all or resonate only when attached to its native large handheld transceiver, which has enough metal inside to behave as a counterpoise, these antennas have SWR 2 or higher. Check your antenna on antenna analyzer before using, add wire counterpoise if needed or better to use dipole or halo home made antenna for that matter - Range (20 KHz channel width and 9 spreading factor, also got similar results with 125 kHz and 12 SF) - **About 7 km** when server is 30m above the ground and client is 2m above the ground with rubber duck antenna or inside a car - **About 13 km** when server is 30m above the ground and client is at some higher point ~40m above the ground with rubber duck antenna