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What is SWR protection?
In the event of a catastrophic storm that damages the roof of the home, one of the ways people can prevent water intrusion is to have what is called a Secondary Water Resistant (“SWR”) barrier.
Why do most solid state amateur radio transmitters reduce output power as SWR increases?
With older radios this was a common problem that needed to be protected against, but most solid-state (read: modern) transmitters automatically protect against that by reducing the power in cases of high SWR so that the reflected power will not cause damage to the transistors in the output amplifier.
Is peel and stick SWR?
peel-and-stick products that qualify as SWR can also be installed on top of a layer of felt, only installations that are attached directly to the wood sheathing can qualify for an SWR insurance discount. There is nothing wrong with this installation; it just does not qualify for an insurance discount.
What is considered a secondary water barrier?
A Secondary Water Barrier is a backup system to prevent water intrusion (through the joints in the roof decking) into the home in the event of the primary roof covering and underlayment being blown off during a hurricane.
What does an SWR of 4 1 indicate?
What does an SWR reading of 4:1 mean? An antenna loss of 4 dB. A good impedance match.
Why does my transmitter back off when the SWR is high?
Transmitters sort of force you to do this by backing off the power when the SWR is high, meaning the load is not 50 ohms. Bypassing the “SWR foldback” and tuning for maximum output power is likely to cause efficiency and distortion to suffer more often than not.
Why does a high SWR create a higher loss?
Actually, except for the losses in the coax, 100% of the energy that leaves the transmitter will be radiated out of the antenna, no matter how high the SWR, because of the re-reflection. A high SWR will create a higher loss in the coax because a higher amount of energy travels backwards in the coax.
Why do you need a SWR meter on an antenna?
The value is when you convert that number back into what it measured in the first place, which is the percent of returning energy. That is why you need a SWR meter. You should always use an antenna tuner.
Can a antenna tuner change the SWR of an antenna?
The antenna tuner can not change the SWR of your antenna, or its coax, so you will need to follow these 7 steps to see what actually happens with a higher SWR than the SWR meter in coax #1 says is there.