[TowerTalk] Re: Tuning coax stubs w/ shack test equipment

[Steve Gehring, KL7DC]

At 01:45 PM 3/30/99 -0500, you wrote:
>
>
>A recent exercise in cutting (153 deg) stubs for 80M
>I discovered that I got better results, a better indication
>of resonance, using a noise bridge & receiver.  An Autek
>RF-1 using the preferred method of tuning for minimum Z,
>just couldn't give me the resolution that tuning through a
>sharp dip on the rx could.  The resonance point of the
>stub was about 4.350 MHz and the coax used was RG-8X.
>
>However, using the RF-1 to cut over 300' of 3/4" CATV
>hard-line to resonance at 3.795 MHz, the instrument
>was easy to to tune to min. Z.  Evidently, the much higher
>Q of the hardline makes it easier to cut to resonance than
>lossier, flexible coax.
>
>In this shack there are never enough test instruments,
>gizmos, what have you, to aid me in building a better station.
>
>
>                 73 de Walt Kornienko - K2WK - zak@goes.com
>

I agree.  There's never enough test equipment around the shack.  Obviously,
the RF-1 isn't perfect, but I feel it suffices for these low Q stubs.  It
has it's drawbacks, like diode suckout, as K6LL mentioned.  

I'm lucky though, I can always take that hunk of line into work and check
it using a $40K HP spectrum analyzer w/ tracking generator.  Boy, do I feel
fortunate.

73 de Steve, KL7DC
Eagle River, AK


--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm