Cable Routing Question

[K3YA]

I'm trying to clean up a very disorganized shack.  I put up some hooks to hold the various cables up near the ceiling, out of the way.  This looks much neater then on the floor! These will be a mix of RF (coax), control, and audio cables (mostly shielded balanced high level, no mike level) and will run all mixed together for up to 25 feet to and from the bigger transmitters.

My question is am I asking for trouble bunching every thing together with the transmitter output coax cables, or should I put up a second set of brackets a few inches below the first set, for the higher power feed lines?  Currently I'm having no issues with the single 250 watt AM transmitter cabling run this way, but I have 2 more transmitters and a couple antenna feed lines to add to the bundle.  Anyone have experience with an instillation like this?

Charlie

[Todd, KA1KAQ]

I try to keep power lines away from RF lines when possible, Charlie.

OTOH, I have run them close to each other, even over each other now (the current set up isn't yet tidied up cable-wise) and aside from occasionally introducing some noise into the scope image, which is more of a scope pickup issue, no ill affects have been noticed. Good shielding of the feed line makes all the difference.

If it doesn't bother you with 250 watts, go for it. If you add a bigger rig and it causes problems, you can always re-hang later.

Heard you chatting with Bill 'HG last night until the crap out. Great signal down here, strong with excellent audio.

[DMOD]

I would have three sets of brackets for the three classifications of cables.

I assume your audio is high level "line" audio. Since it is balanced, I think you will have little problem.

You might still want to put some 330 to 750pf caps on the the inputs and outputs of the audio drivers and receivers to kill any residual RF.

For the control cables, you might want to put those through toroids.

Phil - AC0OB

[KM1H]

I prefer to keep them out of sight either at bench top or just below

I run most everything in bundles in the shack and up to 450' to the top of towers. This includes coax, rotator and relay switch boxes and even the baseband shielded CAT5e cable for a microwave link.

At the shack every rig and amp has ferrite toroids over a short coax jumper, then lowpass filters. The toroids force the RF thru the filter and not around it. Rotator (up to 12 at one time when deep into contesting) and switching cables get a couple of turns thru a toroid at both ends, the recent 31 mix is best but Ive been fine with 77 mix for decades. Ive used 31 to quite some household noise and they do an excellent job.

Amps generally run up to 1500W from 160M to UHF, maybe a bit more on AM No problems at all.

Open wire line is not permitted here

Carl

[k4kyv]

Here's how I do mine.  Might not be recommended for everyone.

Hey, Steve WA1QIX, can you beat this?

[WD8BIL]

Very similar to mine, Don.
I call it the "from here to there" cable arrangement.
Let's see, this cable goes from here to over there. Yup, just long enuf!

[KM1H]

Here's how I do mine.  Might not be recommended for everyone.

Jeez, thats award winning!  How come there is an empty outlet in the Isotap? You must be slipping

[k4kyv]

How come there is an empty outlet in the Isotap? You must be slipping

It doesn't produce the right voltage for anything.

[WA3VJB]

Charlie, the practice in field/portable broadcast environments is to separate the video/audio cable path from the path for AC power.  Crews lay shielded balanced audio and coax video cables at a physical distance from AC power cables.  The temporary setting usually involves the co-mingling of many different "sets" of broadcast gear from various local channels and networks, and EVERYONE cooperates to lay their lines as described.  Next time you see a news event outside somewhere, take a look between the camera position and the transmission trucks nearby.

RF lines, when they happen, are more typically grouped with AC lines than audio/video lines, all based on the priority of protecting the video/audio.  At higher power levels in a shortwave installation, I wouldn't want RF near AC or AF.

In permanent studio environments, the overhead cable trough carries audio/video and ethernet,  delivered down vertical columns to the consoles and other gear, while AC power is distributed in the sub-floor, coming up to the equipment from below. Any RF is low power wireless on a variety of UHF channels for talent mic, talent earpiece, floor director headsets.

[ke7trp]

A neat way to route cables is to use Cable trays.  Sometimes called Cable Ducts. These are cheap plastic U shaped trays that screw to the wall.  They are made up with fingers of plastic and have a snap on cover.  You can run all your cables down this and when you need it to exit, You snap off a finger.  These are often seen in data centers.

http://www.alibaba.com/product-free/104530911/CABLE_TRAY_CABLE_DUCT.html

I dont use them now.  My cables run along the base board. But I dream of an organized shack someday

[WD8BIL]

But I dream of an organized shack someday

"Organized shack" is an oxymoron.

[KC4VWU]

Don,
       I think I saw a couple of Indian Head pennies and a mercury dime back there... when's the last time you cleaned??

[K3YA]

Don,
       I think I saw a couple of Indian Head pennies and a mercury dime back there... when's the last time you cleaned??

I was going to post a photo of my current jumble of cables on the floor, but after reading these comments I'm glad I didn't!  Don your brave man showing those pictures. 

I'm going to separate the run of antenna level coax cables from all the other stuff by a several inches using a second row of brackets.   I put the brackets up high to deal with the several doors that the cabling pass by.

Interesting that the new cables have changed things enough to cause some RF in the audio of a transmitter far removed from the new wiring.  I suspect that RF pickup from the nearby antenna is going to be a bigger issue then any coupling between adjacent cables.

Thanks for all the comments.

[k4kyv]

I use 500/600Ω balanced lines between units of audio equipment, and isolation transformers between the a.c. mains and all the low power equipment in the shack. Nothing on the secondary side the isolation transformers has one side of the a.c. connected to ground/neutral potential; I just leave both sides floating, or else both sides of the a.c. are balanced with respect to ground, via an outboard mid-tapped choke across the secondary.  I pulled a half-dozen IsoTaps out of a dumpster a few years ago, so I have plenty to go around. I just wish they had a built-in mid-tap on the secondary, that I could run to ground directly.

A small variac set to mid-scale makes an excellent tapped choke for balancing a.c. feed with respect to ground.  Ground the variable tap, and bridge the ends of the winding across the secondary of the isolation transformer.  That allows you to fine-tune the balancing adjustment for minimum hum.

The balanced a.c. and audio lines seem to keep the ground loops and rf-in-the-audio to a minimum. Grounding can be a problem; sometimes the measure that takes the 60~ hum out of the audio introduces rf into something else, or vice versa. It can get complicated when you have a bunch of units connected together in a station.

I have just as much rf in the shack when using coax as I do with OWL.

[steve_qix]

I gave up decades ago trying to have neat wiring.  Things are too dynamic in the shack, and I'm constantly adding or changing wiring.

Using balanced lines for audio is key to avoiding ground loops.  Both ends don't have to be balanced, as long as either the input or output is ground isolated and balanced, you're usually OK.  With my audio setup, the output is balanced, and the inputs are generally unbalanced (but not always - some modulators take balanced in).

[k4kyv]

I gave up decades ago trying to have neat wiring.  Things are too dynamic in the shack, and I'm constantly adding or changing wiring.

Same here.  But I think yours might be more "dynamic" than mine.  Yours don't show as much accumulated dust .

[W7TFO]

I don't wanna' hear about dust....


73DG

[steve_qix]

THAT picture shows a dusty place!!! 

I have no idea why I don't have lots of dust in my shack.  To be sure, there is some dust, but I've been using that room for the shack for almost 20 years, and it's NEVER been dusted and rarely vacuumed.

[Todd, KA1KAQ]

Charlie, if you decide to split out some of your cabling you could easily hang some of the larger tie wraps from the current brackets without any extra drilling or more brackets. Large loops would leave plenty of space for adding or changing in the future.

[K5UJ]

But I dream of an organized shack someday

"Organized shack" is an oxymoron.

If you can go into a ham's shack for the first time and sit down and operate everything without having to ask any questions, then it isn't a real shack.

[ke7trp]

Very true.  I do try to take pride in what I do.  TFO has been here. My shack is fairly neat and clean.  Now my work bench room is a different story!

TFO, You need to go in that room with a hazmat suit and an electric leaf blower!


C