Cheap Rotator Control Cable ?

[VK2XTC]

Hi,

I'm trying to source some rotator control cable and was wondering what people are using.

I found some 7 - core Trailer harness cable, for re-wirign a box trailer at Bunnings today.
It seems fit for the task but may be a little heavy. It certainly won't go through a rubber grommet on the rotator connection point. It's too thick.

How heavy does it have to be ? Can you get away with something quite light , say telephony / alarm cable.
What's a good source of rotator cable ?

I have Az and El rotators so will need about 30 meters or 40 meters. So the trailer cable at $4 per meter adds significantly to the installation cost.


Thanks

Brian

[VK3DXE]

Alarm cable works nicely. I scored several boxes of runs left over from commercial jobs a few years ago, and have used that since then. I had some trailer cable, but it was just too fat and heavy to work with, unless you need a 50m+ run.

[VK4AFL]

Hello Brian - Just last Wednesday I purchased off ebay [Melbourne] a 30 metre roll of 7 core cable for $58 delivered & its absolutely perfect.
PM for details if you are further interested.
73, Trevor, VK4AFL.

[VK6OX]

Try here for 30m of 7-core, $47 delivered anywhere in VK.

[VK3ZAZ]

Yes you doo need substantial wire size for the motor current, read the owners handbook
who said alarm cable was OK ???

For HYGAIN
Removed the BIG CAPACITOR
Mount it at the rotor
and run two runs of cheap old three core 240 volt stuff
small tower one roll
Big tower two rolls QED cheap as chips at Cheap as chips..

[VK4TI]

When was the last time you bought a roll of even 1mm2 copper ?
the Korean stuff is cheaper and unreliable so the 7 core looks fairly good

[VK4UH]

I also needed two long runs of six cored cable for an Az-El EME dish rotation system here. I purchased a 100m drum of 7 core trailer cable off e-bay but actually from Melbourne for a little over$120 delivered

I exteriorised the unwanted "pair" of wires, one from each which gives me a spare set for masthead pre-amp/isolation relay operation.

Local prices were also several dollars per metre from the usual car outlets

KJ VK4UH

[ZL3RC]

Not quite the same but I use SPID rotors which only require 4 wires, easy.
Been using Cat 5 network cable for years with pairs twisted together works fine and thats a 45m run to the rotator.
One other trick is to up the volts to compensate for the cable loss. Cat 5 or 6 is very cheap these days and I use it for everything.
You will be surprised the things you can run down it other than rotators, like Composite video, Balanced audio (even un-balanced if its not in the same duct as a mains cable )
Alam cabe is nice and floppy and even has more copper in it than Cat 5 but no twisting of any pairs.

Roger.

[VK2XTC]

Thanks to all that replied. You got love this forum for quick answers to life's little questions.

The reason I asked the question is I purchased a Az / El rotator out of VK4 last week (they will probably pop up on the forum now and say hi) and the manual states the wire as being 2 x 6 core #20 AWG or higher.
Which is 0.8 mm and 1.5amps rated. It also recommends #18 AWG for runs over 100 feet (30 Meters). (1mm and 2.3 Amps)

I looked at the Alarm wire it had connected on it and thought maybe it was just used for testing, as the outer sheath isn't stabilised and the cores look very thin.
The motors run at 24 volts , but it doesn't say how much current they draw. And I was thinking cheap copper over a long distance with a decent current will cause a reasonable voltage drop, which will limit the life of the motors. I thought about Cat 5 as I have reels of that under the house, but it's not stabilised plastic and won't last in the sun. and again not knowing the current requirements.

My thinking was trailer wire and It's tuff, able to take about 8 to 15 amps and UV stable. It's just the price that scared me.
Bunnings had heavy duty cable (10 meters capable of 15 Amps) for $36. (Why 15 Amps ??)
Auto One has something lighter (assuming 8 amps) at approx. $4 per meter off a roll (30Meters for $120)

Thanks for the links to the eBay cheaper stuff. And all the suggestions around Cat 5 etc.

Anyone got any ideas as to the current drawn for a Kenpro KR-5400 ?
What's the current rating of Cat 5 cable as it would be a very cheap fallback for me.



Thanks

Brian

VK2XTC

[VK6OX]

Hi Brian,

According to the 5400B manual, the no-load (cable NOT connected) O/P from the controller to the rotator motors is approx. 30VAC, and the resistance of each motor winding is 4Ω.

From this, you could surmise a maximum operating current of approx. 7.5A.

I would, and do, use the 7-core cable from the VK3 supplier as indicated in my earlier post.

[VK5PJ]

Hi Brian,
I have a run of about 35 metres to my rotator and used the trailer cable in two sections. I have a connector at the bottom of the tower before the cable goes underground to the shack. I used the stock standard trailer plug and socket to make the join (weather tight too), then I can bring the controller to the base of the tower if needed during maintenance of the antennas. I found my cable at a local disposals store in a job lot of other cables.

I have stayed away from light cables as the overall resistance when loaded is going to limit the torque the motor can produce, especially if the rotator has a electro magnet break solenoid like a HAM-M.

Maybe I should not share this tip, but what the hell life has been good to me.... it is coming up to stock take time, go down to your local electrical stockists(s) and ask if they have any drums of cable they do not want to measure or count in their stock at June 30 and you may get a surprise at what you get for a song. My most recent score is some semi armoured 5 core (same size as RG-213) that has multi stand 18 gauge copper and I got the 100M role for $40 (now in use to power my mast head preamps and tower lights)

do not settle for a small cable unless it is a must.

Regards,

[VK2XTC]

Tower Lights ?

As in to stop aircraft hitting it ?

[VK5PJ]

Hi Brian,

Tower Lights ?
As in to stop aircraft hitting it ?

No they are work lights , as the shack is part of the horse stables shed, the HAM tower doubles as a light tower as well (LED 12volt spotlights) so both halves of the family get benifit from the tower (cunning plan to blend A.R into home life)

[VK3UH]

And brilliantly executed, Peter!

[VK2XTC]

Ok,

Being that it's all about how much metal you can get into the air I was feeling rather small for a bit then ...

I ordered the 30M roll of eBay from Victoria, about 11am yesterday, and it shipped that afternoon.
Should arrive before the end of the week.


Brian