Re: Folded up (folding up) the coax on (Tek) probes: not good, right?


Greg Muir
 

Put some similar coax that has been treated this way on a TDR or DTF network analyzer and observe the little reflection bumps at the sharp bends. May not be significant enough for the average probe user but as you progress towards microwave those little bumps become bigger ones.

I had an instance where some coax had been removed from a project and the tech zig-zagged and folded it up in a very tidy and small bundle securing it with a Ty-wrap (total no-no). Over a considerable time the inner dielectric cold flowed just enough to allow the center conductor to move towards the shield resulting in it being dumpster food..

When I receive any cables that have been treated that way I place them in a warm oven to slightly soften the dielectrics then lay them out straight on the floor to allow them to cool. Of course anything attached to the ends does not enter the oven. The most chronic are the IEC power cords that have been bound up so tight by someone that they never straighten out by themselves. Then after cooling they are coiled up the same way a cowboy coils his ropes.

Greg

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