[HBR] Dissipation factor of materials

[Ron Barlow via HBR]

Hi Dan,
 I for one, would certainly like to see the results of a comparison of the Q of your inductor, with a similar inductor, that is wound on a low loss polystyrene, or ceramic form.
 I have no means to measure such results, and my post retirement budget insures that situation will not change.
 The writings of the LOWFERs (from the pre digital days), xtal set experimenters, etc., that were/are in a position that demands the lowest loss circuitry, if good results are expected, have indicated that pvc coil forms are sub optimal.
 It would be very interesting to see some real life measurements.
                          73 de Ron 
--------------------------------------------
On Sun, 11/30/14, Hopperdhh at aol.com <Hopperdhh at aol.com> wrote:

 Subject: Re: [HBR] Dissipation factor of materials
 To: imalowfer at yahoo.com
 Date: Sunday, November 30, 2014, 12:03 PM
  
  
 I made a plate coil
 for a Johnson 
 Messenger conversion to 75 meters that was wound on 3/4
 inch PVC pipe (1 
 1/16 inch OD).  The winding was 31 
 turns No. 24 enameled wire space wound using No. 28 wire as
 a temporary 
 spacer.  This gave 17.9 uH with an unloaded Q of about
 225.  Not bad 
 for a small coil!  This was measured on a Boonton 260
 Q-Meter.
  
 A good experiment would
 be to compare a similar 
 coil wound on polystyrene.
  
 My guess is that the
 small dissipation 
 factor of PVC will not affect the Q enough to
 measure.
  
 This conversion was
 posted on AMfone.net several 
 years ago, but for some silly reason I can't register
 anymore with my aol.com 
 email address!
  
 Dan K9WEK