Subject: MODIFICATIONS FOR THE WILSON MARK II AND MARK IV & MARS



      Please refer to the "Operating and Service Manual" for these radios.

      If you are having trouble getting MARS and CAP crystals to oscillate,

the following four steps should be taken:

                a. change C88 to 4pf.

                b. change C92 to 3pf.

                c. change C98 to 22pf.

                d. change C99 to 22 pf.

                e. Align T10, T11 to produce more than 1 volt on TP2

                   at both ends of the band.

                f. Align T12, T13 to produce more than 1 volt on TP3

                   at both ends of the band.

                g. Align L2 and L3 carefully to produce about the same

                   power output at both ends of the band.

                h. The radio should now be checked on a spectrum analyser

                   to insure clean operation. Of course the normal frequency

                   and deviation checks should also be made.



      For parts location on the circuit board, refer to the X-Ray view in the

   Operating and Service Manual.