Effect of high SWR on transmitter

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In summary, the conversation discussed the effect of high SWR in antenna systems on ham radios. While some believe that an SWR higher than 1.5 to 1 can damage the transmitter's final transistors, others argue that the reflected power from the antenna system will not go back into the transmitter but rather back into the antenna system. However, standing waves can still be created and may have an impact on the transmitter's performance. The question is whether or not the transmitter is affected when the electromagnetic wave reflects back from the antenna system, which could potentially fry the transmitter if the SWR is high enough.
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GhostLoveScore
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I've been reading about effect of high SWR in antenna system on my ham radio. A lot of people are talking something like - You can't have SWR higher than 1.5 to 1, it will blow final transistors of your transmitter.
I've read about it and it doesn't look to be true. In fact, it seems like power reflected from antenna system will not get back into the transmitter, but instead it will reflect back into the antenna system.

But on another side, if I create a short wave on a piece of rope with tied down another end, I will feel the wave when it reflects and gets back to my hand. And certainly, in transmission line, reflected wave comes back and forms standing wave when interacting with original wave. In that case it seems like reflected wave does have some effect.
So my question is, does the transmitter "feel" anything when EM wave reflects back from the antenna system? Can you fry your transmitter with high SWR in antenna system?
 
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GhostLoveScore said:
Can you fry your transmitter with high SWR in antenna system?
Yes.
Depending on the wavelength of the transmission and the length of the feedline to the antenna, standing waves can create high voltages with very low current in the output stage. Transistors do not like that.
 
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Related to Effect of high SWR on transmitter

1. What is SWR and how does it affect a transmitter?

SWR, or standing wave ratio, is a measure of how efficiently a transmitter's power is being transmitted through an antenna. A high SWR indicates that there is a mismatch between the transmitter and antenna, which can result in decreased transmission range and potential damage to the transmitter.

2. What are the potential consequences of high SWR on a transmitter?

High SWR can cause overheating and damage to the transmitter's components, leading to decreased performance and potential failure. It can also result in reduced transmission range and poor signal quality.

3. How can I measure the SWR of my transmitter?

To measure SWR, you will need an SWR meter, which can be purchased or rented from most electronics stores. Connect the meter between the transmitter and antenna, transmit a signal, and the meter will display the SWR ratio.

4. What can cause high SWR in a transmitter?

There are several potential causes of high SWR, including a damaged or poorly installed antenna, mismatched antenna and transmitter frequencies, or a defective transmitter. It is important to troubleshoot and address the root cause of high SWR to prevent damage to the transmitter.

5. How can I reduce high SWR in my transmitter?

If the cause of high SWR is a mismatched antenna, it can be adjusted or replaced to better match the transmitter's frequency. If the transmitter is defective, it will need to be repaired or replaced. Regular maintenance and proper installation can also help prevent high SWR in a transmitter.

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