AM Transmitter Shelter

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Fran3
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Joined: Wed Jun 24, 2015 1:30 pm

AM Transmitter Shelter

Post by Fran3 » Wed Jun 05, 2019 8:07 am

Looking for suggestions on "budget" (new or used) shed/shelter to house a 5kw AM transmitter, 3 phase cabinets, and two or three standard size equipment racks.

This is for a possible transmitter relocation from inside the studio building to the new shed/shelter near the center tower base.

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kkiddkkidd
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Location: Lawrenceburg, TN

Re: AM Transmitter Shelter

Post by kkiddkkidd » Wed Jun 05, 2019 9:38 am

Fran3 wrote:
Wed Jun 05, 2019 8:07 am
Looking for suggestions on "budget" (new or used) shed/shelter to house a 5kw AM transmitter, 3 phase cabinets, and two or three standard size equipment racks.

This is for a possible transmitter relocation from inside the studio building to the new shed/shelter near the center tower base.
What kind of TX?

The first question that needs to be asked is.... Are your feed and sample lines above ground so that they can be moved as well? Or are you going to replace them with new exact replacements.

The prefab concrete cell buildings of various sizes can be found very reasonably priced on the surplus market. Used shelter venders like

https://telepp.com/used-shelters/ are pretty common. Find one near you to save transport costs.

Regards,
--
Kevin C. Kidd CSRE/AMD
WD4RAT
AM Ground Systems Company
http://www.amgroundsystems.com
KK Broadcast Engineering
http://www.kkbc.com

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RGORJANCE
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Location: RACINE, WI

Re: AM Transmitter Shelter

Post by RGORJANCE » Wed Jun 05, 2019 10:06 am

Those cell buildings are really nice. If you go that route, MEASURE YOUR EQUIPMENT TO SEE IF IT WILL FIT IN THE DOOR.

Second the comment on the sampling lines and also the transmission line as the tx lines factor into the phasing of the array.

The other thought is to go with a prefab customized outbuilding set on a concrete slab. Plan carefully for sufficient air handling.

Still another option is a 1 1/2 to two car garage with properly sized entries for your specific needs. The 24/24 ft garage would probably be the best size and also give you ample space for a work area as well.

Plan ahead carefully.........

Fossil

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Deep Thought
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Re: AM Transmitter Shelter

Post by Deep Thought » Wed Jun 05, 2019 1:23 pm

A used prefab concrete communications shelter is the way to go. Most have HVAC built in. You almost certainly won't find one set up for three phase power so keep the expense of swapping out the breaker panel in mind.
RGORJANCE wrote:
Wed Jun 05, 2019 10:06 am
Those cell buildings are really nice. If you go that route, MEASURE YOUR EQUIPMENT TO SEE IF IT WILL FIT IN THE DOOR.

Fossil
^^ THIS ^^ A client substituted a different shelter at the last minute (after all the equipment had been ordered and built) and the door ended up being 4" too narrow for the phasor cabinets. Cutting out the door and replacing it with a wider one cost them nearly $1000.

Also, and most importantly, if you are moving the phasor from one end of the array to the middle the entire system will need to be redesigned to account for the different phase delays due to the different transmission line lengths. This is non-trivial and could end up costing many thousands of dollars to correct.
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com

Fran3
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Joined: Wed Jun 24, 2015 1:30 pm

Re: AM Transmitter Shelter

Post by Fran3 » Fri Jun 07, 2019 10:47 am

Coax to towers and sample lines will remain the same. New location 50 to 100 feet due south of current location and our tower guy tells us he can easily move the existing lines... so, for now, we are hopeful that is true... else... more $$$. (He has also done complete installations so he will be physically moving and reconnecting the equipment)

Used cell phone buildings have been suggested but where the heck to you find them for sale? I can get the Governor on the phone easier than I can any one at the cell phone companies that knows anything.

Thanks for the help.

PS We had also considered a retired 40 to 45 foot refrigerated semi-trailer/storage unit. However equipment access may be tight if all equipment is lined up side by side. Another option is to turn each rack 90 degrees... facing the back of the trailer... with 3 to 5 feet between racks... Anyone seen anything like this?

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kkiddkkidd
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Location: Lawrenceburg, TN

Re: AM Transmitter Shelter

Post by kkiddkkidd » Fri Jun 07, 2019 12:17 pm

Fran3 wrote:
Fri Jun 07, 2019 10:47 am
Coax to towers and sample lines will remain the same. New location 50 to 100 feet due south of current location and our tower guy tells us he can easily

Used cell phone buildings have been suggested but where the heck to you find them for sale? I can get the Governor on the phone easier than I can any one at the cell phone companies that knows anything.
I hope your tower guy is a lot different than most of my tower guy acquaintances.

Google "surplus cell shelter" and "used cell shelter". Your tower guy may know if there is a dealer near you.

Are the lines above ground or buried?

Later,
--
Kevin C. Kidd CSRE/AMD
WD4RAT
AM Ground Systems Company
http://www.amgroundsystems.com
KK Broadcast Engineering
http://www.kkbc.com


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