[TowerTalk] Fwd: RE: SteppIR Wind Damage

[VR2BrettGraham]

Correction: K4MQG, not K6DGW.  Need another cup of tea.
Sorry.  73, VR2BG

>Date: Thu, 30 Nov 2006 00:31:29 +0000
>To: <towertalk at contesting.com>
>From: VR2BrettGraham <vr2bg at harts.org.hk>
>Subject: RE: [TowerTalk] SteppIR Wind Damage
>
>K3MH suggested about SteppIR tubes & lengths:
>
>>Have you tried the re-calibration routine to re-set the element lengths?  I
>>changed tubes and also upgraded my controller 6 months ago.  I apparently
>>had one of the first Steppir versions.  You can alter the default tuning
>>lengths of the driven and other elements.
>
>Calibrate just runs the motor(s) long enough that the
>strips can be assumed to be fully retracted & therefore
>extended from a known state to a known length.
>
>Yes, you can change the element lengths yourself, but
>what length to use on a parasitic element with one
>new tube & one old one?
>
>As K8IA noted, the difference on a driver can easily be
>dealt with - at least based on where the SWR meter is
>along the feeder.
>
>On a parasitic element, finding the correct length for the
>particular tubes being used might not be so easy.
>
>The failure K6DGW QSPed earlier reminded me of thinking
>about this when the new tube mystery first surfaced.  A total
>tube replacement is a no-brainer - you end up with all tubes
>of type same & firmware with dimensions for those tubes.
>
>I hope somebody somewhere might benefit if they stumble
>across this post, but unless the mixed tubes are on a driver,
>I suspect most users will not notice to begin with - a 100 kc
>or two shift in SWR curve can be seen from shack & is
>probably being actively monitored by the user.  The change
>in gain or pattern if a parasitic shifts that much is a bit more
>subtle & is not being watched for so closely (if at all).
>
>73, VR2BrettGraham