Transmission line theory demonstration video

[26OD004]

Hi all,

I am trying to help out a junior engineer at work, who is studying for his full licence. I'm trying to find a video I saw years ago (I think Bob85 posted it iirc). The video was by an American HAM who was giving a demonstration of transmission line theory by using two 20' copper tubes to simulate transmission line connected to an RF generator. He then used a shorting bar with a light bulb in the middle which he could slide up and down the copper tubes to show the voltage/current peaks and troughs and how they changed dependant of the load etc. It was an excellent video and it was great to be able to visualise what the RF was doing.

It was a great easy to understand demo and I would love to find it again, it looked like it may have been filmed in the 80's.

If anyone knows what I'm talking about and can link me the video I would appreciate it In fact any good videos/material that would be easy to understand and help someone moving from a foundation licence to the full/advanced licence would be greatfully received.

 

[BJ radionut]

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[26OD004]

You're a legend, that 2nd vid was the one! Many thanks

 

[brandon7861]

If anyone knows what I'm talking about

You can find many videos like that on youtube. Its called a lecher line and was commonly used to measure frequency. Search for "measuring frequency using a lecher line"

Here's one using copper tubing:

 

[Ranch55]

I always felt this is one of the best videos to demonstrate Standing Wave Ratio to beginners who are learning the concept........
An oldie, but excellent video......

 

[26OD004]

Thanks guys, all the videos have been great, I enjoyed watching them. He'll be a transmission line expert in no time