Installing the Components:
Installing the components is quite easy—just pre-bend the leads, match them to their pads on the pc board, solder them in place, then snip the excess length. Install in the following order, and checkoff each part as it’s installed.
Resistors
( ) 3 - R1, R2, R3 47 ohms 2 Watt Click for picture.
( ) 1 - R4 1k 1/2 Watt Pre-bend leads and install here.
( ) 1 R5 150k 1/4 Watt Prebend leads and install here.
( ) 1- R6 1.5M 1/4W mounted between R4 and R5. Solder it to the LH end of R4 and the RH end of R5. As in this picture.
Capacitors
2 - C1, C2 250p Polyvaricon, Set aside, these will be installed after the Coil.
( ) 3 - C3, C4, C5 0.01u disks Pre-bend like this   and install like this.
Semiconductors
( ) 1 - LED1 Green Pre-bent shapes Note: The flat on the LED body should line up with the silk-screen line at the side of the mounting hole.
( ) 1 - LED2 Red install here. The negative (short) leads are inserted on the side of the board holes with the flat line marking.
( ) 1 - Q1, 2N3904 Pre-bend and trim leads thusly
( ) 1 - Q2, 2N3906 install here.
( ) 3 - D1, D2, D3 1N4148 Pre-bend like this   install here. Note Polarity.
Final Assembly
SW1 Mini DPDT
( ) Install into the board and snug up the mounting nut on the panel.
( ) Cut four 1.25" pieces of green magnet wire, pre-bend them thusly, and tin the ends.
( ) Install the 4 hookup wire wires per this picture.
( ) Add and solder jumper betweenthese two lugs.
SW2 1P12T with toroid assembly
( ) Fit the S1/Inductor sub-assembly to the board, install the washer and nut in the front panel and snug up.
( ) Solder the lead from the center lug to the 10 o'clock pad on the board. as shown here and trim the excess lead.
( ) Solder the ground end of the coil wire to the 7 o'clock pad.
( ) On the front panel, install the knob pointing to A or L, depending on your choice of windings, and tighten the set screw.
BNC Connectors J1, J2
( ) Prebend center conductors as in this photo.
( ) Install on board
( ) Solder the center connectors first so as to stabilize the connectors on the board.
( ) Solder shell connections. Use plenty of heat on the ground connections - 50 watts if you have it. Otherwise wait for the shell to heat up sufficiently to melt the solder.
Polyvaricons C1, C2
( ) Install the nylon spacers with 1/2" screws. Snug firmly but don't overtighten.
( ) Pre-bend the three tabs
( ) Fit to the board
( ) Install and lightly snug the front panel mounting screws, don't overtighten.
( ) Solder the 3 tabs.
( ) Set the trimmers to minimum, i.e. unmeshed. as in this photo
( ) The single pads below the polyvaricons are not used
( ) On the front panel, rotate the LH polyvaricon CCW to the stop and install the knob pointing to 10.
( ) Rotate RH polyvaricon CW to the stop and install the knob pointing to 10.
Assembling the Enclosure
The enclosure measures 3-5/16" x 3-1/8", and the key to matching the sides properly is the number of solder pads on each. The longer sides have 6 total pads, and the shorter sides have 5 pads.
( ) Begin by placing the bottom on your work surface with the solder plated side facing up (toward the interior).
( ) Match the solder pads of the sides to the pads of the bottom.
( ) Then use masking tape to fix one of the sides to the bottom.
( ) Work around the enclosure taping additional sides to each other and the bottom until all sides are in position. The enclosure will look similar to this
( ) Hold sides snugly in place with two rubber bands.
( ) Ensure that all the tabs and notches are fully engaged.
( ) The tension on the sides should insure that they are square to each other. You may wish to verify that by measuring corner to corner diagonally across the top and comparing (they should be identical), or by using a square.
( ) Solder each pad on the sides to the corresponding pad on the bottom. Note that the pads have thermal relief. Your soldering station set to it's highest temperature will provide adequate heat. Use plenty of solder in order to bridge the gap.
( ) Solder each corner pad to it's corresponding pad on the adjacent side.
( ) Assemble the 1-1/2" threaded spacers in each corner by inserting the 6-32 x 3/8" screws through the bottom.
( ) Assemble the top panel with the 6-32 x 3/8" screws.
( ) If you wish, run a black Sharpie® along the sanded board edges so they will blend in better with the overall color.
( ) Assemble the binding posts: remove the nuts, washers and solder lug, then insert the threaded bolt into the holes. Refer to this picture. Reassemble the hardware on the inside of the case with one of the nuts against the enclosure, and snug it up. Then assemble the solder tab, washer, and nut and snug it up also. J3, the red (antenna wire) post is insolated from ground by a gap in the copper around the hole, and is adjacent to the ANT BNC connector (J1). The black post doesnt need to have an extra wire to ground it, as it's grounded through the case, so install it without the lug.
Congratulations! You have completed building the 4S-Tuner, it should look like this.
Using the 4S-Tuner
While this procedure may seem like many steps, in actual practice it only takes a few seconds to accomplish.
1. Switch indicator OUT.
2. Set inductance and capacitance settings to the most band noise.
3. Switch indicator IN.
4. Key the transmitter in tune mode. Note: Don't change inductor settings while transmitting.
5. Rotate the left capacitor knob first, should see dip in the red LED.
6. If not, rotate the right capacitor knob.
7. If no dip, unkey the transmitter and change inductance setting.
8. Key the transmitter again.
9. Rotate the LH poly knob, should see a dip in the red LED.
10. If not, rotate the RH poly knob.
11. Repeat steps 7-10 as needed.
12. Then continue adjusting the polys back and forth in small increments until the RED led completely extinguishes or very nearly so.
13. The green led should be at full brilliance.
14 Unkey the transmitter.
15. Switch indicator OUT for operating. The SWR will be 1:1
16. Record the settings for when you use the same antenna again.

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