OCO request for intermediate/advanced lab
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(1) Hall effect:
     from Klinger-Educational;
     cat.no. 586850 (base unit)    $ 598.--
     cat.no. 586853 n-Ge           $ 819.--
     cat.no. 586853 p-Ge           $ 902.--
                                   --------------
				                         $ 2319.--
							 
    Explanation/justification:
      this experiment has not been operational for a 
      long time since the crystals were destroyed 
      (I do not know how and when -- before my time);
      The original parts from PHYWE had a 
      similar price tag;
      Klinger appears to be a company that is 
       easier to deal with than PHYWE.
      

(2) Bragg scattering with microwaves:
    from CENCO:
    Bragg reflection cube set
     (cat. no. 36860N)               $ 160.--
                                                         $  160.--      

    Explanation/justification:
     We have a set of microwave transmitter and receiver
       (from CENCO) which are presently not used.							 
     we could use this to make a nice new lab. experiment
       to study wave optics using microwave radiation and 
       Bragg diffraction.
     The Bragg cube consists of steelballs suspended in 
        a 5x5x5cm^3 matrix of styrofoam 
	   (transparent to microwaves).
        The balls are removable to allow study of effect of 
	 spacing and density.
      Other equipment needed: 
          function generator and oscilloscope
	   -- can be recycled from old electronics lab.   
	   
	   
(3) ESR experiment:
    from PASCO:
       SE-9635 Basic ESR system  $2875.--
    or Klinger
       514 55 ESR basic unit     $1802.-- )
       514 56 ESR adapter        $ 299.-- )2483.--
       555 06 Helmholtz coils    $ 382.-- )
       
    additional equipment (to be recycled from electronics lab
    and other experiments):
       power supplies, oscilloscope
          
  Explanation/justification:
    This would add an interesting, up-to-date experiment
     to the advanced lab.;
     full setup with control unit would cost about 5.7k$.
     Using parts from other sources is actually preferable 
     from the didactic point of view (using the manufacturer
      supplied control unit makes the equipment look like 
      black box with reduced need to learn what is going on)