NorCal S9 Assy V1
NorCal S9 Assy V1
NorCal S9 Assy V1
1
Contents
1. Introduction ............................................................................................................. 3
2. S9 Specifications ................................................................................................... 3
3. Assembly Notes ..................................................................................................... 4
3.1 Essential Tools and Supplies ............................................................................... 4
3.2 SMT Soldering Tips............................................................................................. 4
3.3 Parts Bag Component Locator ............................................................................. 5
4. Assembly ................................................................................................................. 5
4.1 Bottom Side Assembly ........................................................................................ 5
4.2 Top Side Assembly .............................................................................................. 6
5. Testing ...................................................................................................................... 8
6. Altoids Tin Installation ........................................................................................ 8
7. Circuit Description .............................................................................................. 11
APPENDIX A. S9 Component Layout Top .................................................. 12
APPENDIX B. S9 Component Layout Bottom ............................................ 13
APPENDIX C. S9 Schematic ............................................................................... 14
APPENDIX D. Parts List...................................................................................... 15
Figures
Figure 1. Parts Bag Contents ..................................................................................... 5
Figure 2. SMT Capacitor Color Code....................................................................... 5
Figure 3. Completed Bottom Side ............................................................................. 6
Figure 4. Completed Top Side ................................................................................... 8
Figure 5. Drilled Altoids Tin...................................................................................... 9
Figure 6. Prepared Altoids Tin Ready For Board Installation............................. 10
Figure 7. S9 in an Altiods Enclosure ....................................................................... 10
2
1. Introduction
The NorCal S9 signal generator is a crystal-controlled oscillator which produces
switchable output levels at selectable frequencies. All of the board-mounted components
are included in the kit, all you need to add is a 9V battery. Rubber feet are supplied for
enclosure-free operation, or you can easily fit it into an Altoids tin.
The S9 level is useful for testing and calibrating receiver S-meters while S1 level can be
used for receiver alignment and sensitivity checks. The oscillator works with most
fundamental mode crystals, so you can substitute your favorite frequencies up to 15m.
The output harmonics also can be used to reach into the higher bands.
The majority of the components are surface mount technology (SMT), but are easily
mounted due to wide component spacing. If this is your first SMT kit, be sure to read the
assembly tips section which will guide you to a successful assembly.
2. S9 Specifications
Dimensions 3.5 x 2.125 x 0.6 (HWD), excluding connector
Power Requirements 9V battery, less than 2mA typical
Output Frequencies 3.579 MHz, 7.040 MHz, 10.116 MHz, 14.060 MHz
3
3. Assembly Notes
Lead-based solder is being phased out, but 60/40 or 63/37 tin/lead rosin-core, .010
to .015 diameter solder is suitable for installing the components in this kit. You can
use .025 diameter solder for the thru-hole components. Silver-bearing, eutectic
solder is also acceptable, but not necessary. Do not use solder with an acid-core flux.
4
3.3 Parts Bag Component Locator
Figure 1 shows the bag layout and Figure 2 shows the capacitor color code used in
this kit.
Surface Mount
Components
Color Value
Thru-hole Components
RED .01uF
&
YELLOW 18pF
Circuit Board
VIOLET 47pF
Figure 2. SMT Capacitor Color Code
4. Assembly
If you plan to install the S9 Generator in an Altoids tin, skip ahead to Section 6. Its
easier to prepare the tin before parts are installed on the board.
When youre ready to start building, secure the S9 board to your work surface using
masking tape to prevent movement. Well start building the board with the bottom
side. Refer to Figure 3.
5
C3, Strip color RED
C4, Strip color YELLOW
Q1, marked 1A
C5, Strip color VIOLET
R6, 203
Inspect the solder joints and touch up as required. Figure 3 shows the completed
component installation.
This side includes both SMT and thru-hole components. We will install the SMT
components first. Refer to Figure 4.
6
Double check your work, especially LED1s orientation. Now its time to install
the crystals. The kit is supplied with popular QRP frequency crystals, feel free to
substitute your favorites, up to 21 MHz.
Y1 3.579 MHz
Y2 7.040 MHz
Y3 10.116 MHz
Y4 14.060 MHz
Rough up the tops of the crystals. Use fine sandpaper or an emery
board.
Bend a piece of buss wire to form an L shape.
Insert one end into the ground pad just to left of Y1 and solder the
other end to the top of Y4. Trim the excess.
Solder the wire to the remaining crystals.
Solder the lead to the ground pad at Y1.
Switch installation is next. SW1 can be installed either way. SW2 fits in only one
orientation. The handle of SW3 should protrude beyond the edge of the board. Its
important to solder all of the tabs on SW3 to obtain proper signal attenuation in
the S1 position.
The battery terminals are up next. Make sure that SW1 is set to Off: Handle at
the bottom position. The terminals have some wiggle room, so a battery is used to
orient these properly.
7
J1 solder all tabs
If you plan to operate the S9 Generator unenclosed, install the four rubber feet at the
corners. Smile, youre done! If youre going to install it in an Altoids tin, wait until
testing is complete.
5. Testing
Move SW2 and SW3 to their far left positions. Move SW1 to the down position and
install a fresh 9V battery. Flip up SW1 and check if LED1 is lit. If not, check R1 and
LED1. Make sure the battery clips were installed in the correct locations.
Next, connect a cable from J2 to a CW/SSB receiver tuned to 3.579 MHz. You should
hear a loud tone. Note the receivers S-meter indication. Flip SW3 to the other
position and observe the S-meter. It should have dropped substantially. Repeat this
procedure for the remaining bands.
If you are unable to hear any signal on any band, double-check all of the components
on the bottom of the board and SW2. If the S1 level is very weak, check R7-R12.
8
Align the bare board to the holes and mark the location for BNC jack and output level
switch. You can eyeball the locations and be fairly accurate. A step-bit works very
well for medium to large holes. For the level switch, first drill a hole and then file to
rectangular shape. Frequent alignment checks produce the best results.
The top cover will need to be notched to allow clearance for the BNC jack. You can
snip the metal using wire cutters and file to shape and remove the burrs.
You will need three very short spacers to raise the board off the bottom of the tin. A
height of 0.1 is ideal. You can add an adhesive to hold them in place. A few layers
of electrical tape on the bottom will help insulate the components, as shown in Figure
6. Figure 7 shows the completed assembly.
9
Figure 4. Prepared Altoids Tin Ready For Board Installation
10
7. Circuit Description
The S9 is powered by a 9V battery which should provide long service life because
less than 2 mA are required during operation. R1 drops the battery voltage and
supplies current to LED1, which serves as a voltage regulator and power-on indicator.
The voltage across LED1 is 1.88V +/- 10mV. D1 also serves a dual purpose: it
provides a further voltage drop and provides reverse polarity protection for the rest of
the circuit. The voltage between the cathode and ground is about 1.4V, since the drop
across D1 is about 0.5V due to the low oscillator current. C2 decouples the power
supply.
Q1, R2, R3, R6, C4, C5 and one of the switch-selected crystals form a low power
Colpitts oscillator. The oscillator output is taken from the collector through C3 and
supplied to an attenuator composed of R4 and R5. The attenuator output is nominally
50uV into a 50 load. SW3 selects between the S9 and S1 output levels. A 34dB
attenuator comprised of R7 through R12 provides the 1uV signal output. Two
separate pi networks were used to provide accuracy.
The oscillator output contains harmonics of the fundamental frequency. This is useful
for checking higher bands, but the signal level will be less than the fundamental. You
can install other crystals in Y1 through Y4 at frequencies up to 21 MHz.
11
APPENDIX A. S9 Component Layout Top
12
APPENDIX B. S9 Component Layout Bottom
13
APPENDIX C. S9 Schematic
14
APPENDIX D. Parts List
15