We performed timing and spectral analyses for PSR B1929+10, one of the oldest (~107 years) of the ordinary pulsars detected in X-rays, using archival ROSAT, ASCA and RXTE data. Pulsed emission was detected at a more than five sigma level for the combined ROSAT PSPC-B and previously unpublished HRI data. Our pulse profile is in agreement with that obtained by Yancopoulos et al. (1994, ApJ, 429, 832, ROSAT PSPC-B) but now with better statistics. The pulsed fraction in the ROSAT X-ray band is 0.25 ± 0.04. The pulsed signal has also been detected in the ASCA GIS data (0.5-5 keV) with a similar pulsed fraction of 0.36 ± 0.11. No significant timing signal is found in the RXTE PCA data (>2~keV). We found that the combined ROSAT PSPC-B and ASCA GIS spectrum can satisfactorily be described by a power-law as well as by a double black-body model but not by a single black-body model or black-body plus power law model. Fitting the combined ROSAT/ASCA 0.1-10 keV spectrum by a power-law model we obtain a photon index α of 2.54 ± 0.12 and a neutral hydrogen column density NH towards the source of 9.8-1.0+1.4 × 1020 cm-2. For a double black-body fit our results are T1 = 2.0-0.05+0.05 × 106~K, T2 = 6.9-0.35+0.23 × 106 K and NH = 4.4-1.1+2.1 × 1020 cm-2. In both cases the derived value of NH is higher than that adopted in earlier works, but our result is fully consistent with the larger distance estimate of 331 ± 10 pc from parallax measurements combined with the hydrogen distribution measurements in the direction to the pulsar.
