 
 <prompt> Wetin electromagnetic waves dey jam? Based on di previous question, write one context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: As electro-magnetic wave dey waka through different parts of antenna system (radio, feed line, antenna, free space), e fit jam impedance differences (E/H, V/I, etc.). For each interface wey e reach, based on how the impedance match be, some part of the wave energy go bounce back to the source, come form standing wave for the feed line. The ratio of maximum power to minimum power for the wave fit be measured and e dey called standing wave ratio (SWR). SWR of 1:1 na ideal. SWR of 1.5:1 dey okay small for low power applications where power loss dey important, even though SWR as high as 6:1 fit still work with the right equipment. To reduce SWR and make power transfer pass through each part of antenna system well well, make we reduce impedance differences for each interface (impedance matching). 