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Maker Pro

My old high school gym

CTP4500

Mar 3, 2018
21
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Mar 3, 2018
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21
They use a PA ( phone assistant ) system and and amplifier for all the basketball games. This appears to be two or more seperate systems. The board, the speaker, and the amplifier. Since there is a lot of wires under the bleachers taped, does anyone know how long it takes before the wires start to corrode? Yearly maintenance. Also if the speakers like Kenwood use the standard coaxial cables on all equipment. Will the distance in cabling affect the transmission of sound? Where can I buy extra cable in the local market? Hardly any electronic stores in the area. How much would you charge if they ask you to replace all the corroded and standard cables to newer cables?
 

Hopup

Jul 5, 2015
253
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Jul 5, 2015
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253
If they are maintained in good environment I think they are in OK shape. For that application the wire distance shouldn't matter all that much, voltage drop does occur you can use online calculator for that.
 

kellys_eye

Jun 25, 2010
6,514
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Jun 25, 2010
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6,514
PA stands for 'Public Address'.

The system is usually based on a high voltage audio transmission (50V or 100V) to counter resistive loss in long cables but each speaker requires a step-down transformer at the speaker itself in order to work.

There's nothing special about the wiring however:
if the speakers like Kenwood use the standard coaxial cables on all equipment
AFAIK there are no speaker systems that use 'coaxial cable' - indeed WHY would they? Any copper cable will do and most PA systems I've worked on use simple two-core flex.

As for corrosion - it will suffer like any exposed cable will and depends on the environment. Closer to the sea and you're asking for trouble (salt water) but hot, dry areas not so much. None of the wiring should be exposed due to the potential for shock (although it's not fatal) so joints should be correctly made and insulated.

Find the cost per metre of suitable cable (1.5mm2 2-core will do for most runs), multiply it by the known run length and add your time at whatever hourly rate you charge.
 

LightShow

Jun 9, 2016
111
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Jun 9, 2016
Messages
111
Is the system indoor or outdoor? i dont really see why cables would be in that bad condition.. ive seen systems just like this installed for upwards of 30 years and its still running strong.. yeah definitely the area you live in effects the degradation of the cable but i dont see any reason why it would be corroding? if im way off someone can let me know by all means :D
 
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