LHCb outer tracker prototypes

This note describes measurements performed on various prototype modules of LHCb Outer Tracker drift chambers in the test beam periods of 1998 and 1999. Presented are measurements of various drift cell characteristics. The single cell efficiency is shown to be better than 98%. The gas mixture Ar:CF4:CO2 (68:27:05) in a 5 mm straw tube is just fast enough to keep the maximum drift time within two LHC bunch crossings. It is shown that 8 mm cells do not satisfy this criterium. The noise in the tested 5 mm prototypes is below 0.2%, the main source of this noise is the amplifier/shaper. Next to presenting the measurements, the test beam setup is described. Furthermore a description is given of the used analysis methods. The same methods will be used to analyse the data taken in 2000. This data will be reported in a seperate note.