Just Sharing This Personal upgrade - log periodics

Channel Hopper

Channel Hopper

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So, after a large amount of wind - not mine - and some changes to the roof, I revised the antenna rotator system ( for now ) from the usual Triax Group antennas to Fracarro 45 series log periodics, and serviced the antenna rotating system at the same time.

Some refining required but so far all is going well, less weight on the mast but back rejection might require a bit of fettling.

IMG_0532.JPG
 
Channel Hopper

Channel Hopper

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The antenna rotator thingy , if anyone is interested. I had an additional bearing to fit, but for some reason it doesn't, s o I may have to file things down later

IMG_0539.JPG
 
Terryl

Terryl

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OpenBox X5 on a 1 meter motorized dish.
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It doesn't show the maximum antenna wind load, anything on how much square footage or square metres (or centimetres) before the brakes give out?
 
Channel Hopper

Channel Hopper

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My Satellite Setup
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The original has lasted some 15 years , replaced with same.

All that has changed are two XG8s and boom are now replaced by a pair of LP45s.

Total weight up top is probably 6 kilos less, with somewhat less drag.
 
aceb

aceb

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Prof Tuner 7301 /
1.25m Gibertini + Inverto B.Ultra/C1W, Moteck H180, 68.5E-67W Ku/C-Band /
1.8m Precision PF + ESX241/Inverto Black Pro, 66E-63W Ku/C-band /
2.4m Fortec Star+Titanium C1W/Pride plate, 49E-58W
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Sussex
And a trusty old Triax 8 ele BII too. Nice to see 3 core rotators are still available, where did you buy it?
 
Terryl

Terryl

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2,559
My Satellite Setup
OpenBox X5 on a 1 meter motorized dish.
And now a 10 foot "C" band dish.

Custom built PC
My Location
Deep in the Boonies in the central Sierra Nevada mountains of California.
I was wondering about the overall wind loading, if the antenna(s) is/are pointing 45 degrees diagonal to the wind, how much wind would it take to make the break on the antenna rotor to let loose to move them off the original heading?

My ham antenna rotor has a 1 square meter (M2) wind load, this means that the total antenna wind-loading can be up to 1 M2 for a 60 knot wind, this is where the break on the rotor would let go.

For most 450 MHz 12 element antennas the wind loading would be around .06 M2,, so you should be well within any loading on that rotor.

I found this spec for your new antenna, Windload at 120Km/h (720N/m2) Kg (N) - 3.0(29.43) This force is measured in Newtons, my old brain could not remember the conversion formula.
 
statalite

statalite

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Nova-HD-S2, Dr HD D15, V7S
Zone 1 @ 28.2°E with cable tied LNB @ 19.2°E
Channel Master 1.0m (to be setup)
Free sat v8 finder V-71HD
My Location
UK Midlands
This is not a criticism in anyway but can you explain the reason for 3 of the antennas pointing in the same direction? :Y
 
Terryl

Terryl

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My Satellite Setup
OpenBox X5 on a 1 meter motorized dish.
And now a 10 foot "C" band dish.

Custom built PC
My Location
Deep in the Boonies in the central Sierra Nevada mountains of California.
They are on a antenna rotor, they all need to be pointing the same direction, you can point them any direction using the rotor.
And if you look closely you can see that one UHF antenna is horizontal polarized, the other UHF antenna is vertical polarized, and the last one is for VHF.
 
statalite

statalite

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460
My Satellite Setup
Nova-HD-S2, Dr HD D15, V7S
Zone 1 @ 28.2°E with cable tied LNB @ 19.2°E
Channel Master 1.0m (to be setup)
Free sat v8 finder V-71HD
My Location
UK Midlands
They are on a antenna rotor, they all need to be pointing the same direction, you can point them any direction using the rotor.
And if you look closely you can see that one UHF antenna is horizontal polarized, the other UHF antenna is vertical polarized, and the last one is for VHF.
Ah right as different transmitters can use different polarisations :Y
 
Channel Hopper

Channel Hopper

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My Satellite Setup
A little less analogue, and a lot more crap.
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UK
And a trusty old Triax 8 ele BII too. Nice to see 3 core rotators are still available, where did you buy it?

It was a gift from a friend that has been in storage for a while (the rotator, not the friend). The original was beginning to show its age inside and the bearings were making some funny noises after hours.

20200301_171507[1].jpg
 
Channel Hopper

Channel Hopper

Suffering fools, so you don't have to.
Staff member
Messages
29,712
My Satellite Setup
A little less analogue, and a lot more crap.
My Location
UK
I was wondering about the overall wind loading, if the antenna(s) is/are pointing 45 degrees diagonal to the wind, how much wind would it take to make the break on the antenna rotor to let loose to move them off the original heading?

My ham antenna rotor has a 1 square meter (M2) wind load, this means that the total antenna wind-loading can be up to 1 M2 for a 60 knot wind, this is where the break on the rotor would let go.

For most 450 MHz 12 element antennas the wind loading would be around .06 M2,, so you should be well within any loading on that rotor.

I found this spec for your new antenna, Windload at 120Km/h (720N/m2) Kg (N) - 3.0(29.43) This force is measured in Newtons, my old brain could not remember the conversion formula.

The old rotator managed to work with the two back grid antennas for over a decade, the log periodics have far less profile at any angle. The FM7 is only 60 cms above the parapet and is balanced 50/50 front and rear, its weight has always acted as a stabilising force on the moving pole (4cm steel).

The Unix52 is fixed on the scaffold pole below the rotator , pointing towards Crystal Palace so the family has uninterrupted TV.
 
Adam792

Adam792

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My Satellite Setup
Dishes: 80cm (5°W/4.8°E), 80cm (30°W), 60cm Zone 2 (13°E/19.2°E/28.2°E)
Receivers: HTPC (Intel i3 processor, nVidia Graphics, and TBS6905 4x DVB-S2 PCIe tuner card) running Ubuntu with Kodi/TVHeadend, Wetek Play2, Skybox M3.
My Location
Worcester
Very nice! I'm assuming by Crystal Palace that you're in the South East, do you often manage to pick up French/Belgian signals with your rotor aerials during high pressure?
 
Channel Hopper

Channel Hopper

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A bit far from the coast for that, but to be honest I've never tried.

The main requirement in the past was for the other regional transmitters, local weather and some programmes that weren't broadcast to the London area. Satellite has diminished the need as of late.

The FM aerial however does provide lots of decent audio, none of this comressed DAB/DAB+ rubbish.
 
Channel Hopper

Channel Hopper

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My Satellite Setup
A little less analogue, and a lot more crap.
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UK
Some pictures of the new internal box.

Altai appears to be just one brand name of a batch of identical bits of hardware out there, mainly suppled into the US, but I have seen a number of them previously in northern Italy, for moving the band 4/5 aerials from one transmitter to another when atmospherics knock out a channel or two.
 

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