gareth wrote:
"Roger Hayter" wrote in message
...

It is certainly something to bear in mind when designing circuits for
above 10GHz. My rule of thumb is 'use PTFE', but I have no scientific
justification for that!

My enquiry relates to PolyLactic Acid (PLA) which is what my 3D printer
extrudes, because I wish to use it to produce some insulator blocks for
the HRO-like Catacomb band switching in my "Vapourware" Retro RX.

It it highly temperature dependant and dependant on the base material
it was made from.

For the HF range, typical values range from about 2 to about 16.

Google polylactic acid dielectric constant.



--
Jim Pennino