Hello,
What resolved it was I disabled advanced features: OPTION OPTION OPTION 92
then I re-enabled advanced features OPTION OPTION OPTION 91
That resolved the issue
Bill
> On Aug 27, 2016, at 7:56 PM, StellarCAT <rxdesign@ssvecnet.com> wrote:
>
> If I understand you correctly why not go to a 2:1 pulley system instead of a
> 4:1. Or compromise and use a 3:1! The 2:1 only requires a pulley at the
> attachment point - the top return goes to the raising fixture and the bottom
> goes to the winch. This will 1/2 the force on the cable. Or a 3:1 has a
> pulley at each end - the initial attachment point this time is at the tower.
> Again: less cable used.
>
> I've used all three of these on raising antennas on my test tower for range
> testing. The need to get 130 - 160# antennas up 12' in order to get them on
> the mast that is held by a Razor - all by myself pushed me to these options.
> I ended up with the 4:1 but only because it was easier on myself - the 100'
> of rope needed wasn't an issue for me. Note you'll need to add in frictional
> losses in the pulleys to the equation as well - they can be quite substantial
> if the pulley is not using ball bearings.
>
> Gary
> K9RX
>
> [if I misunderstand the application - apologies.]
>
>
> -----Original Message----- From: Roger (K8RI) on TT
> Sent: Saturday, August 27, 2016 7:26 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Strength of installation raising cable for the LM470?
>
> When installing the LM470 using the raising fixture, the retracted tower
> is raised from horizontal to vertical. The cable attaches to the tower
> roughly half way out presenting one whale of an initial load on the
> cable and winch.
>
> Does anyone have the strength listed for the original cable? It's
> roughly a quarter inch galvanized steel. Unfortunately the strength for
> this size and kind of cable varies widely over more than 2 to 1.
>
> I'm planning on replacing the single straight pull with a double pulley
> (rated at 32 kN = 7,193.8# )
> http://www.convertunits.com/from/kN/to/pounds at the tower and a
> single pulley back at the raising fixture. This means I'm going to need
> a longer cable. The existing cable isn't quite long enough to make the
> 4 trips between the tower and raising fixture. Fortunately the new
> method reduces the stress on the cable by a LOT. The cables available
> at the hardware store would likely be strong enough and they do carry a
> selection of strengths, although my preference is for using one of the
> established cable suppliers on the net.
>
> BTW: As for cable flexing there is the drum on the winch, the original
> pulley on the raising fixture plus the 3 additional pulleys between the
> tower and raising fixture. Fortunately these extra pulleys are only
> used when installing, taking the tower down, or laying it down for
> inspections. I would add that the larger, pulleys rated for 32kN and
> up, get expensive. I did find a couple rated for 2000# at the hardware
> store, but when I went back for more the strongest the had was only
> rated for 800# A pair of single pulleys can be used in place of the
> double pulley and the pair of those pulleys rated for 2000# was about a
> quarter the list price for the Aluminum pulleys rated at 32 kN.
>
> The multiple pulleys do reduce the linear stress on the cable, but each
> time that cable goes around a pulley the strands slide back and forth
> against each other, increasing wear on the cable.
>
> I haven't been able to find the strength of the original cable. Searches
> on the net have become extremely difficult. Regardless of what search
> engine I use, it take me through multiple layers of other search
> engines, changing what used to take a minute or two into a long, arduous
> selection process.
>
> As for rusting, or corrosion those raising pulleys don't have to be left
> in place as they see so little use. Just oil them well before putting
> them in storage.
>
> 73
>
> Roger (K8RI)
>
>
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