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 WARNING:
Connecting your scope channel directly to the high power side of the RF system without any attenuator or dummy load will result in serious damage to the scope and possible personal injury.

 

Dummy Load /Attenuator: Basics

Theory of Operation:

The illustration above shows a "dummy Load" being used as a signal "Attenuator". To make this device an RF Load you would terminate the OUTPUT side with a 50 Ohm terminator and connect the source to the INPUT side. The Load is designed to handle rf power for short periods of time, which will allow you to perform tests on the RF system without using the coils as a load.

The Dummy Load/Attenuator is a dual function device. It can act as a Load to absorb and dissipate RF energy or as an attenuator or device that will reduce the RF energy to a level that is usable by basic test equipment. Dummy loads/Attenutators are rated at many different power ratings, usually in dB (decibels) or Watts. Make sure you have one large enough to handle the job. A 30dB attenuator is large enough to handle 16Kw and is found in all GE RF Test kits. 

There are two types of Dummy Loads / Attenuators in use by GE MR Service. One is Grey, has fins and is oil cooled, (Oil filled). and the other is Black with larger fins and is Air cooled. Either model can be used. They are interchangeable for test applications.

There is a distinct INPUT and OUTPUT side. Failure to connect high power sources to the INPUT side will result in a catastrophic failure of the Dummy Load/Attenuator and possible injury to the service person. Be sure you have connected the Dummy Load/Attenuator in the test circuit correctly. Testing the Dummy Load/Attenuator.