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43
Install voltage regulator U3 (78L09) to the left of relay K6 at the
center of the board.
Install jumpers across the solder pads of R29 and R39 in the center of
the board (See Figure 29). The PCB’s green coating is a good insulator,
but it is best to leave clearance under the jumper for R29 to avoid the
possibility of a short.
Figure 29. R29 and R39 Jumpers.
i
If you are not wearing a grounded anti-static wrist strap, touch an
unpainted, grounded object before performing the next step. Once the
temporary jumper across L1 is removed, Q3 is particularly sensitive to
electro-static discharge (ESD) damage until inductor L1 is soldered in place.
Remove the temporary jumper and install L1, the larger gray variable
inductor in the space next to trimmer capacitor C1.
Unscrew and remove the tuning slug from L1. The tuning slug will
not be used.
Install the two blue variable inductors near the upper left corner of
the board:
__L10 __L11
Unscrew and remove the tuning slugs from L10 and L11. They will
not be used.
Locate the shielded inductors with gray inserts provided for L12, L13
and L14 in the R.F. Bandpass filter. Prepare the inductors for installation
as follows:
Use the inductor alignment tool to exercise the core in each
inductor. If the alignment tool fits tightly, insert it from the
bottom to avoid pushing the inductor out of the shield. Run the
core up and down through the coil to ensure it runs smoothly
(some inductors are very stiff at first) then position the core near
the top of the coil.
Check the two leads and the two tabs on the case of each
inductor. If they are bent, straighten them carefully using long
nose pliers.
Install the RF Bandpass Filter inductors in the spaces provided
between relay K2 and frequency mixer Z1:
__L12 __L13 __L14
