EMRFD Index, CD, and Software Errata
  (18 April 09)

p500, index.   Add both "IL" and "insertion loss" to the index with "in filters...p3.1,  in receiver roofing filters...p6.50" (10Aug03)

Book CD:  We have found a minor problem with the CD.  When the CD is inserted, a file "articles.pdf" appears on a directory listing of the CD drive.   Double clicking this file causes it to run under the Adobe reader.  Then, any of the articles included on the CD can be viewed by clicking on the listing in the "bookmarks" along the left screen margin.   But the file for W7EL's "Optimized QRP Transceiver" sometimes produces an error message.  It can be viewed if it is the first file called after the "articles.pdf" file is run.   (20Mar03)    [I have not yet checked this one, and it may be fixed on the second printing.   w7zoi 30Sept03]

Computer Design Programs DTC and TTC (from CD):   Both of these programs include an estimation of the insertion loss for the bandpass filters designed by the programs.   This is an estimation based upon the equation given on p 3.10 of the book.  If a better loss number is needed, the filters should be stored with the file|save_as command, and then analyzed with the general purpose ladder analysis program, GPLA.    GPLA is not an approximation, but an exact analysis based on the ladder method, presented in detail in Intro. to RF Design, p51.   See also RF Design Magazine, Sept/Oct., 1983.   Although GPLA is exact, it is limited by the element models used.   That is, capacitors have no series inductance and no loss; inductors have no parasitic capacitance.    The analysis is limited to simple ladders with no mutual elements  other than those between adjacent elements.

The new programs in LADPAC08 no longer contain the insertion loss estimate.   Instead, other parameters are presented that may be of use to the filter designer.