Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Communication Breakdown; Distraction
ATC Issue All Types
Flight Crew Requested ATC Assistance / Clarification
ATC Equipment / Nav Facility / Buildings; Procedure
MMSD Air Traffic Control Tower combines their Local Control and Clearance Delivery on the same frequency.  I believe this is a dangerous practice.  During our preflight; we contacted Ground Control to request our clearance.  We were told to contact Tower for that.  While monitoring ground frequency; we heard several other flights request their clearance and then told to go to Tower frequency.  When we went to tower; the controller was clearing aircraft for takeoff and landing while simultaneously issuing clearances.  Tower was spending more time reading clearances than controlling.  Because of the language barrier; several aircraft had to have their clearance read back several times thereby clogging up (jamming) the Tower frequency.  During our takeoff; just as we started to apply takeoff power; another aircraft started to read-back their ATC clearance.  Because of the timing of this; we were unable to communicate with the Tower.  And; the Tower would not have been able to communicate with us on the frequency.  If we needed to reject or if the Tower needed to notify us to reject; there was no way to do that because the radio was jammed.  Additionally; the distraction caused by the other aircraft jamming the frequency made it very difficult for me to concentrate on my takeoff procedure duties.  My First Officer; who was the Pilot Flying; also complained that it was hard to stay focused during the takeoff; rotation and gear up calls.  This is the second time this scenario has happened to me at MMSD and this is the second time I've written a report over this issue. Tower frequency is being used as a Clearance Delivery frequency. Tower frequency needs to be used exclusively for controlling aircraft.  Clearances should be requested and received on a different frequency.  Either on Ground Control frequency or a dedicated CD frequency.
Air carrier Captain reported MMSD uses Tower frequency for both clearance delivery and local control; resulted in miscommunication; frequency jamming; and distractions on takeoff.