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Note to Mortuary contributors: please consider that your boss may not find your submission in the best interests of your Big Company. Once in a while we get a "please remove my submission" email, try not to send us anything that you might regret.

Note to Big Companies: Don't blame us for posting your spectacular failures, we only post what your employees send us. On the other hand, please don't rip off Microwaves101 pictures for presentations without permission, that's bad manners. Maybe it's time for some training!

October 2018: This picture came in from Dave, and we admit, it took us a minute to find the problem.  Look closely - can you see where they went wrong?

September 2018: From "Anonymous", this is a photo of the clean room at an unnamed facility...ick.

Here's a submission from David, who received this from a customer for calibration.  We aren't sure calibrating will fix that needle!

New for May 2018: From Tom.  Why is it soldered this way?

Close up of FET in an amplifier

New for April 2018: This came from Dave, title is "Coax Dielectric Loss".

Located problem at approximately 263 feet...opened the line 9 sections up from the base of the tower and confirmed that this was the location of the failure.  It was necessary to clean six transmission line sections above the failure due to contaminants from the burned Teflon. Nine transmission line sections below the failure were also cleaned due to the soot contaminants from the burn.

During the cleaning the crew found a black and charred ty-rap inside the transmission line above the failure point. We suspect that the original failure was due to a ty-rap that has now been completely burned up. There was no damage to the inner conductor or the expansion joint and the only point of failure was a break down of the Teflon insulator. The insulator had to be contaminated with some foreign object or material in order to breakdown and burn as is in this case.

Another ty-rap was found approximately three transmission line sections below the failure point.

 

Editor's note: just because something is white and plastic, does not mean it has excellent microwave properties like Teflon.  If a ty-wrap has poor loss tangent and is exposed to high electric field strength, it can heat up and eventually burn. Foreign object/debris (FOD) is a real problem in manufacturing hand and maintaining hardware.

Update from Tom

Here's what the remaining amps look like inside:

 


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