Yebes Report
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Software --

  Field System:
  We are running a Debian Sarge PC with Field System 9.10.3 and Linux kernel 2.6.8-4-686. 
  We discovered that the serial ports at the main board do not work correctly when 
  being used for the 57600 bauds for the VLBA terminal. Hence we are using a multiport 
  card from Digi. THis finding took us much time and effort and we believe it may affect 
  many modern PCs. We recommend other stations to not rely on serial ports on mainboards
  and use specialized cards instead.

  We are using GPIB devices using the free software driver. Operation is nice and shows no
  problems.

  Connection between the Field System and the antenna is done via the shared memory. Any other 
  connection is difficult since the control system uses ACS (Alma Common Software) which in turn 
  needs clients written in C++, Java or Python. Linking C++ programs with the Field System
  is very difficult since for example, the latter uses C++ reserved words. This has posed 
  problems even to use the shared memory mechanism. The way it works is through private 
  variables which are examined by daemons and trigger operations at the antenna or receivers.

  Mark5B:

  We are running SDK7 firmware 11.99. This version apparently works well with SATA and PATA disks.
  Linux distribution is Debian sarge, kernel 2.4.27-3-686.

Antenna --

  We completed our first VLBI observations with the 40m antenna last May.
  Observations were at 22 GHz. Some problematic issues were discovered during
  the observations. Some of them have already been solved but others are still
  pending. We are working to solve them before next EVN session.

  The antenna still needs to be fully characterized at 22 GHz. The pointing model
  is aceptable but not good enough. Focusing is good but we would like to refine it.
  The surface accuary needs to be calculated carefully as well as the gain curve.

  Single dish X and S observations were done for the first time during summer. Pointing
  is good. S band shows a big interference due to the Profibus modules used to control
  and monitor Nasmyth mirrors and the antenna main drives. We plan to screen cables and 
  modules to reduce interferences. SEFD for X band is 200 Jy. S band not yet measured 
  carefully. 

  On september 12 we took part for 8 hours in a geodetic observation as tagalone. Results
  have not yet been received and we have no confirmation of fringes.

Receivers --

  Available receivers are: K, standard X, extended X and S band, both circular polarizations.
  C band will be installed before end of 2008.

e-VLBI --

  Telefonica, the spanish former national telephone company, is installing an optical fiber
  to connect Yebes to our national node in Madrid. Part of the fiber has already being layed
  but most of the way is still pending. We hope the installation will be finished by the end 
  of this year. The bandwidth will 1 Gb/s.