  Minimax and maximin problems are investigated for a special class of
functions on the interval $[0,1]$. These functions are sums of translates of
positive multiples of one kernel function and a very general external field
function. Due to our very general setting the obtained minimax,
equioscillation, and characterization results extend those of Bojanov, Fenton,
Hardin, Kendall, Saff and Ambrus, Ball, Erd\'elyi. Moreover, we discover a
surprising intertwining phenomenon of interval maxima, which provides new
information even in the most classical extremal problem of Chebyshev.
