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Technical Tips from Mark W. Persons
BE AM5E Cooling Fan Improvement

Front side of the popular Broadcast Electronics AM5E, a solid state 5 KW AM Transmitter.   Inside the door are control boards that operate the transmitter.  They tend to run quite warm after the transmitter has been running for a while.  The cabinet cooling system draws air in at the bottom rear and pushes it past the power modules, then by the control boards on its way out the top.         
You can help the cooling along by installing two exhaust fans at the top of the transmitter to push air out.  They can be on the inside of the cabinet and to redirect exhaust air around the control boards and out of the transmitter.

One choice is to use two 120 VAC fans and wire them in series to 240 VAC power near the bottom of the transmitter where two inline 1 ampere fuses were installed for safety.  Those fans are Thermocool G13538HAS, available from MP Jones as item number 17778FN, or equivalent.

The good part, in this instance, is that no new holes needed to be drilled in the transmitter cabinet.  The fans mounted in existing cooling holes with #6 bolts and nuts. 

The result was a cooler running transmitter. 

Much of the transmitter's exhaust air now comes out from the left side of the top of the transmitter.  If you look carefully, you can see the bolts holding the fans under the top plate. 

The goal is to reduce heat in the control section and extend the life of transmitter components. 

The stories go on and on.  Stop in again sometime.  I'll leave the soldering iron on for you. 
Mark W. Persons   Ham ham W0MH      

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