[Heathkit] Heathkit Spiral Shield.

[lee]

Within the Heathkit DX-100 there is a shield Heath calls a  "Spiral Shield". 
The thing looks like a tightly wound spring and is around 5 inches long.  It 
is grounded on both ends plus in the center.  It's around 1/4 inches in 
diameter and has a small hook-up wiring running through it.  The wire 
connects the Crystal Oscillator/ Buffer tube to the switch which selects a 
crystal or VFO.

Why did Heathkit use the "Spiral Shield" rather then a shielded cable?  I am 
thinking they wanted a connection with low capacitance coupling to ground 
yet wanted shielding.  (More capacitance would have an effect on a crystals 
frequency and pull it down).   I'm thinking the "Spiral Coil" was cheap in 
price compared to a low capacitance shielded cable and that is why they 
employed it.

Can anyone confirm this is the reason for it's use or was there some other 
reason?

Lee, w0vt