[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Shrink wrapped secondaries



Original poster: "Paul Nicholson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <paul-at-abelian.demon.co.uk>

Terry wrote:
> I moved some of the boxes and such out of the way and repinged it:
> http://hot-streamer-dot-com/temp/02090701.CSV

Gives:

PK  FREQ kHz (Error +/-)    Q FACTOR (Error +/-)   LEVEL
 1  351.735 (0.01%,35Hz)     297.08 (0.17%, 0.5)  -0.3dB
 2  872.299 (0.01%,87Hz)     255.28 (1.17%, 3.0)  -14.1dB
 3 1263.252 (0.01%,126Hz)    192.63 (1.66%, 3.2)  -21.4dB
 4 1598.432 (0.01%,160Hz)    147.94 (6.64%, 9.8)  -25.7dB
 5 1905.136 (0.01%,191Hz)    117.28 (15.79%,18.5) -28.7dB
 6 2198.658 (0.01%,220Hz)     95.57 (31.58%,30.2) -28.0dB
Accounted for 97.26% of input signal

    Before     After
f1  351.16     351.735 
q1  275.08     297.08

A worthwhile increase in q1 there.  Those boxes must have been
soaking something up.  q3 went up a little, and the higher mode 
q factors stayed about the same.

All the higher mode frequencies dropped a little.  Opposite to what
I'd expect - again!   There's something funny about this coil.

It might be an LGE (little green elve) effect, or it could be that
the ends of your tube are sealed to give an airtight tube and the
variations in ambient pressure are causing the tube to expand/contract.

The variation is too much to account for by temperature change alone,
unless your temperature changed by more than about 30 degC between
tests!  Deformation of a sealed tube by varying pressure was not 
factored out of the qvar results, which might explain a few things.

--
Paul Nicholson
--