Watkins-Johnson Company WJ-8718A/MFP Instruction Supplement page 55

WJ-8718A/MFP INSTALLATION AND OPERATION
extracting the lower 5 bits of detection mode data, which are placed in Q. In step 15, the r6
contents are shifted right five places; the three LSBs of the data word now contain the
bandwidth code and all other bits are zeros. This data word is placed in R.
Steps 23 through 42 of the program place the data (derived in steps 8 through 22) in
the string reserved in step O. For example, in step 24, if
Q
= 29, the selected detection mode is
AM (Table 2-22); A is placed in the 3rd place and M is placed in the 4th place in the string
("AM"_$ 3, 4).
If the receiver under control is equipped with the 10
Hz BFO Option, Register 0
(rl) will contain the BCD 10 1 frequency digit.
In program step 43, the contents of r1 are
compared to 9. If the register is used, the decimal equivalent of the binary-coded data word
will be less than 9, and the contents of r1 will remain intact. If the register is unused, all bits
will be high, or greater than 9, and a 0 will be loaded into r1 (if r1
>
9; 0
>
r1).
In the remaining steps of the program, the calculator is instructed to display the
receiver address and the parameters in the following order: R/L status, detection mode,
bandwidth, gain mode, BFO sign, three digits of BFO frequency, signal strength, and seven
digits of RF tuned frequency.
2-31