Re: Ecoflex 15?
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For > 432MHz I have used Andrew Heliax 1/2" Superflexible ,foam dielectric cable for turning loops and LDF450 A for straight runs .
LDF450 will survive without loss increase upto the point where the outer solid copper shield starts to crack - this material is substantial and NOT any kind of thin film construction.
Amateur uses tend to put cables into areas that are not specified as suitable by the original manufacturers .This includes contesting - I used to operate with G4RFR and our various reels of 450 were stored in 5Ft rolls , used approximately 8 times a year over a 15 year period .Failure was low and by far the largest failure seen was due to miss handling during setup,strip down .In some cases it survived where a bend had caused the outer shield to flatten and was reformed (not good practice ! ).
People get put off using it , I think , because it is stiffer than UR67 and terminations are "expensive" .
This issue can be solved by using a bored out backnot and turning up a small brass impeadance transformer for the inner solid copper (or plated Alum) conductor .
Design in most UK Microwave Amateur books .I have on occasion formed one using a 1/2" pillar drill and a flat hand file .
The assemblies can be fully soldered and if this is taken through the Hex backnut will stop suck outs to well above 10GHz .
It is not good value to spend a long time building low noise kit and deploying shonky cables that act as resistive pads or actual noise sources .
At least the current crop of handheld VNAs can tell you where it's all gone Pete Tong
This topic will be repeated ad nauseum ......
On Thu, 18 Feb 2021 at 00:01, Robin Szemeti - G1YFG <robin@...> wrote: