ELECRAFT W2 User manual

ELECRAFT
W2 WATTMETER
OWNER’S MANUAL
Revision D, February 10, 2012
Copyright © 2012, Elecraft, Inc.
All Rights Reserved

2
Contents
Introduction...............................................................................................................................................3
Customer Service and Support .................................................................................................................3
Technical Assistance.......................................................................................................................................3
Repair / Alignment Service............................................................................................................................. 3
Specifications............................................................................................................................................4
Display Unit........................................................................................................................................................4
Directional Couplers (Sensors) ........................................................................................................................... 4
Operation ..................................................................................................................................................5
Front Panel..........................................................................................................................................................5
Rear Panel ...........................................................................................................................................................6
Directional Coupler (Sensor) .............................................................................................................................. 7
Computer Interface..............................................................................................................................................7
Firmware Updates...........................................................................................................................................7
SWR Alarm Function...................................................................................................................................... 8
Kit Assembly............................................................................................................................................8
Preventing Electrostatic Discharge Damage.......................................................................................................8
Tools Required....................................................................................................................................................9
Assembly Procedure............................................................................................................................................9
Display Unit Assembly ...................................................................................................................................9
Directional Coupler.......................................................................................................................................16
Appendix A Parts List ............................................................................................................................17
W2 Circuit Boards............................................................................................................................................. 17
Enclosure........................................................................................................................................................... 17
W2 Hardware (E850356)..................................................................................................................................18
Cables................................................................................................................................................................19
Sensors .............................................................................................................................................................. 19
Appendix B – Schematic Diagrams........................................................................................................20
Appendix C – Power On Modification...................................................................................................26
Important Operating Notes for Modified Units................................................................................................. 26
Installing the Jumper.........................................................................................................................................26
iElecraft manuals with color images may be downloaded from
www.elecraft.com.

3
Introduction
The Elecraft W2 is a versatile, auto-ranging RF power and SWR meter that utilizes remote sensing. Up to two
remote sensors can be attached, with various power and frequency ranges available (see Sensors, page 19).
Sensors use standard CAT5 shielded or unshielded cables.
The W2 includes adjustable, high-brightness LED bargraphs for both forward power and SWR. These allow you
to keep track of transmitter or amplifier performance at a glance, even in low lighting or across a large room.
The power bargraph's full scale ranges are 2, 20, 200, and 2000 watts, with either manual or automatic range
selection or peak- hold capability.
A PC-compatible serial interface is included, allowing easy firmware upgrading via the internet, as well as
configuration of the W2's advanced features. Your W2 includes an interface cable for connection to our
computer’s USB port or RS232 port, depending upon which cable was ordered with the W2 (see pg 19).
Software applications can use the serial interface to accurately read forward power, reverse power, and SWR
from both sensors. This is ideal for remote control as well as customized meter displays.
Also provided is a general purpose alarm output (open-drain) and amplifier keying input/output jacks. The latter
can be used to interrupt amplifier keying on power or SWR alarm conditions.
Subsequent sections provide full specifications, operating information, and assembly instructions for building
the no-soldering kit version of the W2.
Customer Service and Support
Technical Assistance
You can send e-mail to [email protected] and we will respond quickly - typically the same day Monday
through Friday. Telephone assistance is available from 9 A.M. to 5 P.M. Pacific time (weekdays only) at
831-763-4211. Please use e-mail rather than calling when possible since this gives us a written record of the
details of your problem and allows us to handle a larger number of requests each day.
Repair / Alignment Service (We want to make sure everyone succeeds!)
If necessary, you may return your Elecraft product to us for repair or alignment. (Note: We offer unlimited email
and phone support to get your kit running, so please try that route first as we can usually help you find the
problem quickly.)
IMPORTANT: You must contact Elecraft before mailing your product to obtain authorization for the
return, what address to ship it to and current information on repair fees and turnaround times. (Frequently we
can determine the cause of your problem and save you the trouble of shipping it back to us.) Our repair location
is different from our factory location in Aptos. We will give you the address to ship your kit to at the time of
repair authorization. Packages shipped to Aptos without authorization will incur an additional shipping charge
for reshipment from Aptos to our repair depot.

4
Specifications
Display Unit
Size (H x W x D) 1.8" x 6.1" x 4.5" (4.6 cm x 15.5 cm x 11.4 cm), not including connectors.
5.1” (13 cm) deep including connectors, LEDs, rear panel brightness control.
Weight 11.7 oz. (0.33 kg)
Supply voltage 9-16 VDC maximum (10-15 VDC recommended)
Current drain 50 mA idle, 650 mA max, 300 mA typical
Directional Couplers (Sensors)1
Size (H x W x D) 2.5" x 2.3" x 5.0" (6.4 cm x 5.8 cm x 12.7 cm), not including connectors.
Weight 7.5 oz. (0.21 kg) typical
Power Range: (200W Sensor) 0-2W, 0-20W, 0-200W, Auto
(2 KW sensor) 0-20W, 0-200W, 0-2000W, Auto
Accuracy: +/- 0.5 dB typical
Frequency Range: (HF Sensors) 1.8 - 54 MHz
(VHF Sensors) 144 - 450 MHz
Sensor Cable: 5’6” (168 cm) 8-conductor Ethernet (CAT 5) with RJ45 connectors.
1One Sensor is required. Two may be connected to the display unit at the same time.
Elecraft's 1-Year Limited Warranty
This warranty is effective as of the date of first consumer purchase (or if shipped from factory, date product is shipped
to customer). It covers both our kits and fully assembled products. For kits, before requesting warranty service, you
should fully complete the assembly, carefully following all instructions in the manual.
Who is covered: This warranty covers the original owner of the Elecraft product as disclosed to Elecraft at the time of
order. Elecraft products transferred by the purchaser to a third party, either by sale, gift or other method, who is not
disclosed to Elecraft at the time of original order, are not covered by this warranty. If the Elecraft product is being
bought indirectly for a third party, the third party's name and address must be provided to Elecraft at time of order to
insure warranty coverage.
What is covered: During the first year after date of purchase, Elecraft will replace defective or missing parts free of
charge (post-paid). We will also correct any malfunction to kits or assembled units caused by defective parts and
materials. Purchaser pays inbound shipping to Elecraft for warranty repair, Elecraft will pay shipping to return the
repaired equipment to you by UPS ground service or equivalent to the continental USA and Canada. Alaska, Hawaii
and outside U.S. and Canada actual return shipping cost paid by owner.
What is not covered: This warranty does not cover correction of kit assembly errors. It also does not cover
misalignment; repair of damage caused by misuse, negligence, or builder modifications; or any performance
malfunctions involving non-Elecraft accessory equipment. The use of acid-core solder, water-soluble flux solder, or any
corrosive or conductive flux or solvent will void this warranty in its entirety. Also not covered is reimbursement for loss
of use, inconvenience, customer assembly or alignment time, or cost of unauthorized service.
Limitation of incidental or consequential damages: This warranty does not extend to non-Elecraft equipment or
components used in conjunction with our products. Any such repair or replacement is the responsibility of the customer.
Elecraft will not be liable for any special, indirect, incidental or consequential damages, including but not limited to any
loss of business or profits.

5
Operation
Typically the W2 is inserted between the transmitter and an antenna tuner, if one is used. The W2 then displays
the SWR presented to the transmitter. If the W2 is inserted between the antenna tuner and antenna, it will show
the antenna's unmatched SWR. The power reading may be less accurate when the unmatched SWR is high.
The purpose and operation of each control and indicator on the front panel is described below. On the next page
the rear panel is shown with descriptions of the cable connections and functions of each connector and control.
Front Panel
IMPORTANT NOTES:
1. An automated power-on test cycles all of the front panel LEDs on and off when the POWER button is
pressed. Also, the PTT RY (see Note 3 on the next page) cycles; you can hear it click in a quiet
environment.
2. If the Alarm function is set, all the front panel LEDs will flash if the SWR exceeds 3:1 until you reset the
W2 by pressing either the SENSOR or the RANGE button. See SWR Alarm Function on page 8.
3. The SENSOR, RANGE and PK HOLD settings you select are automatically reinstated after the power
has been turned off.
4. The power display is not affected by the SWR.
5. If two sensors are connected, the W2 can be made to search for the sensor receiving RF. Hold the
SENSOR switch until the S1 and S2 LEDs alternately flash, indicating the W2 is searching. When RF is
applied the active sensor LED will light steady. When RF is removed, the search operation will resume.

6
Rear Panel
REAR PANEL CONNECTOR NOTES:
1. A power cable is provided with your W2 with a mating connector for the W2 at one end
and tinned leads for connecting to a power supply at the other end. An RCA plug is also
supplied that you may connect to use the 12VDC accessory output on the back panel of
the K3. Normally you must push the power ON/OFF button to start the W2 after 12VDC is
applied. If you’d like the W2 to run on automatically when power is applied, a simple mod
is required to add a jumper inside the unit. This modification is described in Appendix C of
this manual.
2. Remote Signaling Connector: Provides an alarm output, dropping from +5V to ground
when the SWR exceeds 3:1 (see note 3 below) on the connector ring. Connector tip is a
logic (0-5V) input provided for possible future use.
3. Remote PTT Control: Relay switched loop-through provided to disable a transmitter or
exciter for high SWR protection if the SWR Alarm is set (see SWR Alarm Function on
page 8.
4. PC Data (Optional): Provides an RS232 data interface that may be used to connect the
W2 to a personal computer. See Computer Interface on page 7 and Appendix B for
details.
5. Sensor 1 and 2: A suitable cable is provided with each Sensor unit to connect it to the
display.

7
Directional Coupler (Sensor)
A directional coupler is used to measure RF power and standing wave ratio (SWR). A typical directional coupler
is shown below. At least one sensor must be connected to the W2.
Computer Interface
The computer interface provides access to advanced functions controlled through your personal computer (PC).
A suitable interface cable is included to connect your W2 to your computer through a USB or RS232 port,
depending upon the cable you chose when ordering your W2. The W2 Utility program for your computer may
be downloaded free from www.elecraft.com.
Firmware Updates
From time to time, updated and improved firmware may become available for the W2. The latest firmware may
be downloaded from Elecraft and installed using the optional PC interface and the W2 Utility program. Updated
program files may be obtained in two ways. You can check the box in the W2 Utility that says “Copy new files
from Elecraft into local folder”. This will download the latest production released firmware. Optionally, you can
download the new file from the Elecraft web site manually and place it in a local folder, then browse for it
within the W2 utility. This is the way to access the latest Beta firmware available from Elecraft.
A new firmware load is initiated by turning the W2 off, then holding the SENSOR button depressed while
pressing POWER to turn the W2 on. The green 1LED on the power bar graph will blink indicating the W2 is
ready for new firmware.
When you start loading new firmware, the green 1LED on the power bar graph will turn off and the yellow 2W
LED will start flashing as new data is received. If the 2W LED stays on but doesn’t flash, data is not being
received by the W2.

8
SWR Alarm Function
If set, the SWR Alarm will cause all the LEDs to flash in unison if the SWR exceeds 3:1 and triggers the relay
that opens the circuit between the center pins of the PTT RY phono connectors. The SWR Alarm function must
be enabled each time the W2 power is turned on.
Send an ASCII character a to the W2 to toggle the alarm on or off. This may be done using the W2 Utility
program Command Tester screen. The W2 will respond with a1; indicating the alarm is set or a0; indicating the
alarm is disabled. If an alarm occurs, reset the W2 by pressing either the SENSOR or RANGE buttons.
Kit Assembly
Preventing Electrostatic Discharge Damage
Sensitive components in your W2 are may be damaged by Electrostatic Discharge (ESD) in any location or
climate unless you take specific steps to prevent such damage. Many components can be damaged by static
discharges of only a few volts: far too little for you to notice.
ESD damage may not be apparent at first. The damaged components may not fail completely. Instead, the
damage may result in below-normal performance for an extended period of time before you experience a total
failure.
We strongly recommend you take the following anti-static precautions (listed in order of importance) to ensure
there is no voltage difference between the components and any object that touches them:
Leave ESD-sensitive parts in their anti-static packaging until you install them. The packaging may be a
special plastic bag that allow static charges to flow harmlessly over their surface, or the component’s
leads may be inserted in conductive foam that keep them at the same potential. Parts which are
especially ESD-sensitive are identified in the parts list and in the assembly procedures.
Wear a conductive wrist strap with a series 1-megohm resistor that will constantly drain off any static
charge that accumulates on your body. If you do not have a wrist strap, touch a ground briefly before
touching any sensitive parts to discharge your body. Do this frequently while you are working. You can
collect a destructive static charge on your body just sitting at the work bench.
WARNING
DO NOT attach a ground directly to yourself without a current-limiting resistor as this poses a
serious shock hazard. A wrist strap must include a 1-megohm resistor to limit the current flow. If
you choose to touch an unpainted, metal ground to discharge yourself, do it only when you are
not touching any live circuits with any part of your body.
Use a grounded anti-static mat on your work bench.
If you choose to use a soldering iron to work on your W2 for any reason, be sure your iron has an ESD-
safe grounded tip tied to the same common ground used by your mat or wrist strap.

9
Tools Required
1. #0 and #1 size Phillips screwdrivers. Use the screwdriver that best fits the screw in each step. To avoid
damaging screws and nuts, a power screwdriver is not recommended.
2. Needle-nose pliers.
The following tools are strongly recommended:
1. ESD wrist strap.
2. Static dissipating work pad.
Assembly Procedure
Before starting construction, do a complete inventory, comparing the parts in your kit with the parts list in
Appendix A, to familiarize yourself with all of the parts and to ensure the kit is complete.. If any parts are
missing contact Elecraft for a replacement (see Customer Service and Support, page 3).
Display Unit Assembly
Mount two standoffs and two 2D fasteners on the bottom of the main board as shown in Figure 1.
Figure 1. Installing Hardware on Main Board.

10
Place the 1/8” (2.9 mm) spacer under regulator U3 and temporarily secure it as shown in Figure 2. It is
important that the spacer stay in place so it won’t fall out later when you remove the screw to mount the bottom
cover.
Figure 2. Installing U3 Spacer.
Locate the display board assembly. Handle the assembly carefully to avoid misaligning the LED’s Check
the front panel board for a nylon screw at the two corners with its head toward the rear (side opposite the LEDs)
as shown in Figure 3. If necessary install a 2-56 5/32” (4.0 mm) nylon screw at each location. These screws are
inserted until the heads just touch the PC board. They don’t hold anything. When the W2 is fully assembled, the
heads of these screws serve as “bumpers” that press against 2D fasteners in t he case to keep the front panel
board from flexing when buttons are pressed.
Figure 3. Nylon "Bumper" Screws in Front Panel Board.
Press one gray keycap onto each of the three pushbuttons on the front panel boar d (see Figure 4)
Figure 4. Installing Pushbutton Key Caps.

11
Mate plug P1 on the bottom of the main board with jack J1 on the front panel board as shown in Figure 5.
Note that one pin on P1 has been removed and a plug is placed in the corresponding hole in J1. This is to help
avoid misaligning the connectors. Be sure the connectors are aligned and fully mated as shown.
Figure 5. Mating the Front Panel and Main PC Boards.
Locate the bottom cover and remove the paint from the inside around the corner screw holes as shown in
Figure 6so the cover will form good electrical contact with the standoffs and 2D fasteners when it is mounted.
Figure 6. Preparing the Bottom Cover for Mounting.

12
Remove the screw holding the spacer between U3 and the pc board and mount the bottom cover as shown
in Figure 7. Be careful not to dislodge the spacer. If it falls out, you must remove the cover and replace it as
shown in Figure 2.
Figure 7. Mounting Bottom Cover.
CAUTION
Do not put stress on the pc boards when installing the screws in the following step.
Secure the bottom cover with four 3/16” (4.0 mm) black pan head screws. No lock washers are used. Note:
It is best not to tighten the screws until the enclosure is fully assembled so the panels can move slightly as
needed for best alignment. This is a good practice to follow when installing all of the outer case
components.

13
Install a 1/4” (6.4 mm) black pan head screw into the mounting hole for the PTT RY connector as shown in
Figure 10. Do not tighten this screw! It only threads into plastic. Stop turning when the head reaches the back
panel. Even though you don’t tighten the screw, it provides critical support to keep the connector from flexing
when connectors are inserted.
Figure 8. Installing PTT RY Connector Screw.
Locate the front panel cover and remove the paint from around the screw holes on the inside surface to it
will make good contact with the other case parts (see Figure 9).
Figure 9. Preparing Front Panel Cover for Mounting
Fit the front panel cover over the LEDs so the holes on the bottom line up with the remaining open holes in
the bottom 2D fasteners. Check the adjacent LEDs carefully to ensure they are all aligned in even rows. If
needed, gently adjust their position for best alignment. This is best done with the cover off.
Secure front panel cover to the 2D fasteners with two 3/16” (4.0 mm) black pan head screws.

14
Mount 2D fasteners with 3/16” (4.0 mm) black pan head screws at each end of the rear panel cover as
shown in Figure 10 (A). Install one fastener at each end of the panel. Do not use lock washers.
Mount 2D fasteners with 3/16” (4.0 mm) black flat head screws at each end of the front panel cover as
shown in Figure 10 (B). Install one fastener at each end of the panel. Do not use lock washers.
Figure 10. Mounting Front and Rear Panel 2D Fasteners.
Clean the paint from around the holes on the inside (flat) side of the side panels as needed to ensure good
electrical contact with the 2D fasteners when they are mounted. Note that there is a left and a right side panel.
They are not interchangeable because of the beveled holes for flat-head mounting screws. Be sure to scrape the
paint only from the flat, inside surfaces as shown in Figure 11.
Figure 11. Preparing the Side Panels for Mounting.

15
Mount both side panels on the W2 display unit using three 3/16” (4.0 mm) black flat head screws in each
panel. Do not use lock washers. Start all the screws in each side panel before tightening them to make fitting the
panels easier.
Make a final check of the screw securing U3 on the main pc board with the screw that runs through the
bottom cover. Be sure the nut is tight against the board.
NOTE
The RJ45 connector, J3, on the main pc board inside the W2 is used only for initial
programming of the board at the factory. That’s why it’s hidden inside the W2.
Clean the paint from around the four holes on the inside surface of the top cover just as you did for the
other covers.
Mount the top cover, sliding it on from the rear so the REM connector fits through the hole in the back.
Secure the cover with two 3/16” (4.0 mm) black flat head screws on the top and two 3/16” (4.0 mm) black pan
head screws at the back. Do not use lock washers.
Mount the four self-stick feet on the bottom cover as shown in Figure 12. Take care not to bridge the seam
between the bottom and front panel.
Figure 12. Mounting the Feet on the Bottom Cover.
Make a final check of all the external case screws to ensure they are tight, except for the screw at the rear
panel PTT RY connectors shown in Figure 8 on page 13.
That completes the assembly of your W2 Display Unit.

16
Directional Coupler
The directional coupler sensor used to provide RF Power and SWR a measurement is furnished completely
assembled and tested to ensure the greatest measurement accuracy. We recommend you do not open the unit.
The interior of a typical directional coupler is shown in Figure 13.
Figure 13. Typical Directional Coupler Sensor Interior View.

17
Appendix A Parts List
W2 Circuit Boards
ILLUSTRATION DESCRIPTION QTY.
ELECRAFT
PART NO.
W2 Main PCB Assembly 1 E850353
W2 Front Panel (FP) PCB Assembly 1 E850354
Enclosure
ILLUSTRATION DESCRIPTION QTY.
ELECRAFT
PART NO.
Front Panel 1 E100340
Bottom Cover 1 E100342
Right Side Panel 1 E100344
Left Side Panel 1 E100343
Top Cover 1 E100341

18
W2 Hardware (E850356)
ILLUSTRATION DESCRIPTION QTY.
ELECRAFT
PART NO.
2-D Fastener 6 E100078
4-40, Lock washer, #4, Split Z 7 E700004
Black Pan Head
(Typical)
4-40, Screw, 1/4” (6.4 mm), Black, Pan Head 1 E700009
4-40, Screw, 3/16” (4.0 mm), Black, Pan Head 16 E700015
4-40, Screw, 1/2” (13 mm), Black, Pan Head 1 E700030
4-40, Screw, 3/16” (4.0 mm), Black, Flat Head 10 E700025
4-40, Nut, Hex, Zinc 1 E700011
2-56,Screw,1/4” (6.4 mm) ,Pan Head ,Nylon, 2 E700147
4-40, Standoff, Round 1/4” (6.4 mm) 2 E700026
#4,Spacer, Round, 1/8” (3.2 mm) 1 E700140
1/2 X 1/2 (13 mm X 13 mm),Rubber Foot,
Self-Adhesive 4 E700024
Keycap Gray 3 E980027

19
Cables
These cables are provided with both the factory-assembled and kit versions of the W2.
ILLUSTRATION DESCRIPTION QTY.
ELECRAFT
PART NO.
Power Cable (An RCA connector is
included for use with rigs such as
the K3 that have a female RCA
power jack for accessories)
1 E850361
Sensor Cable (this cable may be
packaged with each sensor) 1 per Sensor E850368
Serial Cable Assembly, either RS232 or
USB (chosen when ordering the W2).
RS232 cable shown. 1
E850369
(RS232)
E980192
(USB)
Sensors
ILLUSTRATION DESCRIPTION QTY.
ELECRAFT
PART NO.
Directional Coupler 1.8-54 MHz
200 W
See note
E850364
Directional Coupler 1.8-54 MHz
2KW E850365
Directional Coupler 144-450 MHz
200 W E850370
Note: Up to two sensors may be connected to one display unit.

20
Appendix B – Schematic Diagrams
5 5
4 4
3 3
2 2
1 1
D D C C B B A A
Rt Angle at Rear Panel
Pin 4 is keyed
Mount on Bottom Cover
2009030901 A W2 Power Meter
B
11Saturday, August 22, 2009
Title Size Document Number Rev Date: Sheet of
PWRHOLD SENSOR MUXB PWM RXD
RCK SER MCLR MUXA MUXB
SRCK SER RANGE SENSOR
PGD PGC MCLR
VSCL2
VREF1 VSCL1 VSCL1 SCALE1 VSCL2 SCALE2 VFWD1 VFWD2 SENSE2
VREF1
VREV1 VFWD1
VFWD2
VREF2
VREV2 VREF2
VREV2
TXD TXD MUXA MUX0
MUX0
SCALE2 SCALE1
POWER PWRHOLD
SWSENSE
RXD
SENSE1
MUX1
SENSE1
PGC PGD
SWSENSE
SRCK
RCK POWER
RANGE SENSE2
ALARM
PWM
MUX1
SELECT
VREV1
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V +5V
+5V
+5V
12VUNSW
+5V
+5V +5V
+5V
12VUNSW
VLED
VLED
12V
12V
+5V
VLED
C24 0.01 uF
R22 120R
J1 SENSOR 2
1 2 3 4 5 6 7 8 9 10
K1 G6E-134P
7
10 12
1 6
R11 1K
C1 0.01 uF
TP1 GND
1
J6 2.1mm
1 2 3
C26 0.01 uF
R16 10K
R27
100K
R15 1K
J5A SJD-3512-33
1U 4U 5U
C3 0.01 uF
R18 47K
R5 1K
MTG6 GND
1
U1
PIC18F2520
1
2 3 4 5 6
7 8 9
10
11 12 13
14 15 16
17 18
19 20
21 22 23 24 25 26
27 28
MCLR
RA0/AN0 RA1/AN1 RA2/AN2 RA3/AN3
RA4
SS/RA5 VSS OSC1 OSC2
RC0 RC1 RC2
SCK/RC3 SDI/RC4 SDO/RC5
RC6 RC7
VSS VDD
RB0 RB1 RB2 RB3 RB4 RB5
PGC PGD
R36 1M
R29 1K
13
2
C5 0.1 uF
R32 30K
Q6 2N7002K
1
32
C20 0.01 uF
R24 10K
Q1 2N7002K
1
32
J3 ICD-2
1 2 3 4 5 6
TP5 GND
1
FB2
BEAD
FB1 BEAD
R2 1K
R19 120R
C11 0.01 uF
R17 10K
Y1
16.0 MHz
C6 22 pF
D4 S1M
C15 0.01 uF
R33
10K
D1 BAT54
1 3
TP4 +5V
1
R9 10K
C34 0.1 uF
C13 0.01 uF
MTG3 GND
1
J5B SJD-3512-33
1L 4L 5L
Q4 2N7002K
1
32
Q2
2N7002K
1
32
R41 1M
TP3 SPARE
1
P1 FP
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16
C9 0.01 uF
C25 0.01 uF
R38 1M
R20 120R
+
C31
10 uF/25V
R14 1K
U3
NJM317F
1
2 4
3
ADJ
OUT
TAB
IN
C18 0.01 uF
C19 0.01 uF
R6 1K
R7 10K
Q7 2N7002K
1
32
C30 0.1 uF
D2
MMBD914
2 3
R8 1K
MTG5 GND
1
R23 10K
R3 1K
C37 0.1 uF
TP2 SPARE
1
U2
CD74HC4052M
1 2
3
4 5 6
7 8
9
10 11 12 13 14 15
16
Y0 Y2
Y
Y3 Y1 INH
VEE VSS
A1 A0 X3 X0 X X1 X2
VCC
J2 SENSOR 1
1 2 3 4 5 6 7 8 9 10
J4A RCJ-22XX
3
1
R28 240R
R25 1K
C14 0.01 uF
R42 1M
FB3 BEAD
C2 0.01 uF
C28 0.01 uF
Q5 ZXTP2029FTA
1
2 3
R37 1M
R21 120R
R12 1K R1 1K
C33 0.1 uF
+
C35
10 uF/25V
C22 0.1 uF
U4
UA78M05
1 2 4
3
+VIN GND TAB
OUT
C27 0.01 uF
R4 10K
MTG2 GND
1
MTG1 GND
1
C7 22 pF
R13 1K
R26 22K
C12 0.1 uF
R31 10K
C16 0.1 uF
C4 0.01 uF
J4B RCJ-22XX
2
1
R40 1M
R30 240R
R39 1M
D3
MMBD914
2 3
C23 0.01 uF
C36 0.1 uF
R34 1K
C29 0.1 uF
C21 0.01 uF C10 0.01 uF
R35 1M
C17 0.01 uF
+
C32
10 uF/25V
R10 1K
Q3
MMBT3904
1
2 3
MTG4 GND
1
C8 0.01 uF