  We study the angular dependence of the flux from partially synchrotron
self-absorbed conical jets (proposed by Blandford \& K{\"o}nigl). We consider
the jet viewed from either a side or close to on axis, and in the latter case,
either from the jet top or bottom. We derive analytical formulae for the flux
in each of these cases, and find the exact solution for an arbitrary angle
numerically. We find that the maximum of the emission occurs when the jet is
viewed from top on-axis, which is contrast to a previous result, which found
the maximum at some intermediate angle and null emission on-axis. We then
calculate the ratio of the jet-to-counterjet emission for this model, which
depends on the viewing angle and the index of power-law electrons.
  We apply our results to the black-hole binary Cyg X-1. Given the
jet-to-counterjet flux ratio of $\gtrsim$50 found observationally and the
current estimates of the inclination, we find the jet velocity to be $\gtrsim
0.8c$. We also point out that when the projection effect is taken into account,
the radio observations imply the jet half-opening angle of $\lesssim 1^{\rm
o}$, a half of the value given before. When combined with the existing
estimates of $\Gamma_{\rm j}$, the jet half-opening angle is low, $\ll
1/\Gamma_{\rm j}$, and much lower than values observed in blazars, unless
$\Gamma_{\rm j}$ is much higher than currently estimated.
