  We present high resolution VLA images taken at the wavelengths of lambda 20
cm, lambda 6 cm, and lambda 3.6 cm in the vicinity of the pulsars PSR B1706-44
(PSR J1709-4428) and PSR B1643-43 (PSR J1646-4346). Both of these pulsars are
young (<30,000 yrs) and have large spin-down luminosities (e+35 erg/sec) and
hence are good candidates to search for extended synchrotron nebula excited by
the relativistic pulsar wind. For PSR B1643-43 we found evidences of a
4'comet-shaped nebula, suggestive of a synchrotron ``wake'' left by a fast
moving pulsar. PSR B1706-44 appears surrounded by a spherical nebula
approximately 3 ' in diameter. Based on their morphology, the detection of
significant linear polarization (>20%), and their flat radio spectra
(alpha=0.25-0.3, where S_nu aprox nu^-alpha) we argue that these are wind
nebulae powered by the rotational energy loss of the respective pulsars.
