Pacific Antenna Easy Receiver kit User manual

Pacific Antenna 40M Easy Receiver Kit
Description
The Easy Receiver kit from Pacific Antenna is designed to be easy to build and use. It covers approximately 7 kHz
of the 40M band and can be assembled in about 1-2 hours.
It has no toroids to wind and only one adjustment (trimcap) to set the frequency.
It is a direct conversion design employing a front end bandpass filter, NE602 mixer and LM386 audio amplifier.
Our Easy Receiver is designed to work with our Easy Transmitter, Easy Audio Filter, Easy Tuner and Easy Keyer and
Easy TR switch to make a complete QRP station.
These boards are designed so that, if desired, they can be stacked together to produce a compact assembly.
Support
PACIFIC ANTENNA
Web:www.qrpkits.com
Email: [email protected]
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ools Needed
□ Soldering Station or 1 -3 watt soldering iron with small tip.
□ Solder 60/40 or 63/37 Tin-Lead
□ Small Diagonal Cutters
□ Small Needle Nose Pliers
□ Pencil, Pen, and/or Highlighter
□ BRIGHT work light
Optional
□ Magnifying headpiece or lighted magnifying glass.
□ Multi-meter
□ Solder Sucker and/or Solder Wick
□ Small multi-blade Screw Driver
□ Knife or Wire Stripper
□ Small Ruler
□ Cookie Sheet to build in and keep parts from jumping onto the floor.
Construction echniques
□ There is no need to print out the whole assembly manual unless you want a copy. Print the Parts List and
Schematic then view the rest of the manual on a computer, laptop, or tablet.
□ The Parts List has columns for inventory and construction.
□ Please take time to inventory the parts before starting. Report any shortages to QRPKITS.com (In many
cases it may be faster and cheaper to pull a replacement from your parts supply, but please let us know if
we missed something.)
□ Use the first column to check the parts as you inventory them.
□ Use the second column to check the parts as you install them.
□ Pre-sorting the resistors and capacitors can speed up the assembly and reduce mistakes.
□ You can insert several parts at a time onto the board. When you insert a part bend the leads over slightly
to hold the part in place, then solder all at the same time. Clip the leads flush.
□ Most parts should be mounted as close to the board as possible. Transistors should be mounted about
1/8” above the board. Solder one lead on ICs or IC sockets and then check to make sure the component is
flush before soldering the remaining leads.
□ If you are a beginner, new to soldering, there are a number of resources on the web to help you get on the
right track soldering like a pro. Google Soldering Techniques.
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Parts Identification:
Note: Parts included in the kit may vary slightly from those shown in photograph. This is due to changes in
manufacturers or suppliers and does not affect the kit performance.
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Inventory and Parts List
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Inventory Inst. Qty Parts Value Identification Description
1R9 10 Ohm brn blk blk gold RESISTOR, 1/4W , 5%
1R7 150 Ohm brn grn brn gold RESISTOR, 1/4W , 5%
1R8 10K Ohm brn blk org gold RESISTOR, 1/4W , 5%
1R6 47K Ohm yel vio org gold RESISTOR, 1/4W , 5%
1R4 100 K Ohm brn blk yel gold RESISTOR, 1/4W , 5%
1R10 33 K Ohm Org org org gold RESISTOR, 1/4W , 5%
1R1 4.75K 1% yel vio grn brn brn RESISTOR, 1/4W, 1%
1R3 432 1% yel org red blk brn RESISTOR, 1/4W, 1%
1C4 4.7pF 4.7 CAPACITOR, disk ceramic
1C5 27pF 27 CAPACITOR, disk ceramic
1C7 150pF 151 CAPACITOR, monolythic
1C22 180pF 181 CAPACITOR, monolythic
1C9 220pF 221 CAPACITOR, monolythic
2C11, C12 470pF 471 CAPACITOR, monolythic
3C2, C10, C16 1000pF 102 CAPACITOR, monolythic
60.1uF 104 CAPACITOR, monolythic
3C15, C18, C19 10uF 10 uf ELEC. CAPACITOR 25V+
2C17, C21 100uF 100uf ELEC. CAPACITOR 25V+
3L1, L2, L3 3.3uH org org gold silver INDUCTOR, molded
1D2 1N5234 234B (glass body) DIODE, Glass
1D1 1N5401 1N5401 DIODE, Large Black Plastic
1D3 1N5817 B 1N5817 DIODE, Small Black Plastic
2SC Sockets IC Sockets, 8 pin
1IC2 LM386N 4 LM386N Audio Power Amplifier, 8 pin Ic
1IC1 NE602 NE602A NE602 or SA612, 8 pin IC
1C6 50pF brn Trimmer capacitor, brown
1R5 10K A A10K Green Potentiometer, Volume
1R2 10K B B10K Green Potentiometer, Tuning
1BNC BNC BNC Antenna Connector
1Phone Jack Audio 3.5mm Mono Audio Jack
1Battery Conn. 9V 9V Battery Connector
12” Wire Wire 2 12 inch sections Hookup wire, 2 colors
2Knob Knobs .55” knobs
Small Knobs for Potentiometers
1PCB PCB Rev 1A or B Easy RX Circuit Board
C1, C3, C8,
C13, C14, C20

Inserting the Parts
First, install the two IC sockets, making sure to match the end with the notch to the board outline.
□ 2 SC Sockets IC Sockets, 8 pin
Resistors
Sort the resistors by value insert and solder them smallest value first, largest value last. Be sure to check the color
code for each resistor as you install. [Measuring with an Ohm meter is also a good idea.]
□ R9 10 Ohm brn-blk-blk-gold
□ R7 1 0 Ohm brn-grn-brn-gold
□ R8 10K Ohm brn-blk-org-gold
□ R10 33K Ohm org-org-org-gold
□ R6 47K Ohm yel-vio-org-gold
□ R4 100 K Ohm brn-blk-yel-gold
□ R1 .7 K 1% yel-vio-grn-brn-brn
□ R3 432 1% yel-org-red-blk-brn
Ceramic and Molded Capacitors
First insert and solder the molded capacitors.
□ C4 4.7pF 4.7 CAPACITOR, disk ceramic
□ C 27pF 27 CAPACITOR, disk ceramic
□ C7 1 0pF 1 1 CAPACITOR, monolithic
□ C22 180pF 181 CAPACITOR, monolithic
□ C9 220pF 221 CAPACITOR, monolithic
□ C11 470pF 471 CAPACITOR, monolithic
o C12 470pF 471 CAPACITOR, monolithic
□ C2, 1000pF 102 CAPACITOR, monolithic
o C10 1000pF 102 CAPACITOR, monolithic
o C16 1000pF 102 CAPACITOR, monolithic
□ C1 0.1uF 104 CAPACITOR, monolithic
o C3 0.1uF 104 CAPACITOR, monolithic
o C8 0.1uF 104 CAPACITOR, monolithic
o C13 0.1uF 104 CAPACITOR, monolithic
o C14 0.1uF 104 CAPACITOR, monolithic
o C20 0.1uF 104 CAPACITOR, monolithic
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Electrolytic Capacitors
Now insert and solder the electrolytic capacitors. These capacitors are polarized. The positive hole is marked on
the circuit board with a + symbol. The negative lead of the capacitor is also marked with a black bar on the side of
the capacitor. This lead should go in the pad away from the + marking.
□ C1 10uF 10uF ELECTROLYTIC CAPACITOR 2 V+
□ C18 10uF 10uF ELECTROLYTIC CAPACITOR 2 V+
□ C19 10uF 10uF ELECTROLYTIC CAPACITOR 2 V+
□ C17 100uF 100uF ELECTROLYTIC CAPACITOR 2 V+
o C21 100uF 100uF ELECTROLYTIC CAPACITOR 2 V+
Remaining Parts
□ L1 3.3uH org-org-gold-silver INDUCTOR, molded
□ L2 3.3uH org-org-gold-silver INDUCTOR, molded
□ L3 3.3uH org-org-gold-silver INDUCTOR, molded
□ D2 1N 234 234B (glass body) DIODE
□ D1 1N 401 1N 401 (Large Black) DIODE
□ D3 1N 817 1N 817 DIODE
□ IC2 LM386N Audio Power Amplifier, 8 pin Ic"
□ IC1 NE602A NE602, 8 pin IC
□ C6 0pF brown trimmer capacitor,
Note: C6 has a flat and round side. It should be installed so that the flat side is oriented toward C
The last parts to install are the potentiometers. The A10K and B10K identification marks are on the back of
the pots and are a bit difficult to read. Use lots of light. The pot marked A10K is the 10K Audio Pot. The
pot marked B10K is the Linear Pot.
□ R A10K Green Potentiometer, Horizontal, Audio
□ R2 B10K Green Potentiometer, Horizontal, Linear
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Board Layout
Final Assembly and Packaging
Your easy receiver kit is now completed. Packaging is left up to the builder. However, for testing, you will find included in
the package, an audio connector, 9V battery connector and a BNC along with hookup wire. For initial testing, you can just
temporarily connect short wires to the board pads and use alligator leads for connection of antenna and audio out.
Connections are shown by the diagram below
To power your receiver, you will need to supply a source of clean dc power in the range of 9-12V to JP2. This can be from a
battery source or a well filtered dc supply. An inline fuse of 1A or less is recommended if a DC supply or 12V battery is used.
An inline fuse along with diode D3 serves to protect against reverse polarity damage to the receiver components.
For REV1B and later boards, the connections for power audio and antenna input along with ground are labeled on the board.
For earlier board versions, verify by looking at the back of the board to determine which pin is ground as it differs from the
REV1B layout shown above.
A speaker or headphone jack should be connected to JP3as shown by board labels. The supplied audio jack is for 3 pin
stereo headphones or amplified speakers so the ring and tip should be connected together at the jack for both channels to
be fed audio from the single output of the receiver.
Antenna input is through JP1. The BNC connector that is supplied can be used for connecting an external antenna or
alternatively, a section of wire at least 8-10ft long can just be connected to JP1 as a temporary antenna.
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Connections to Board
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Setup and esting
The Easy Rx has a tuning range of approximately 0-7 kHz. This will cover the low end of 40M for example where
most of the CW activity is found including QRP frequencies such as 7.030 and 7.040.
First verify that when you power up the Easy Rx, and connect an antenna or section of wire, you should hear static
and maybe some signals in the headphones. Turning R2 ( the left side potentiometer) will change the received
frequency and R (the right side potentiometer) will adjust the volume of the background static and any signals
received.
To setup the receiver for the desired frequency range, only one adjustment is required. This is to set the trim
capacitor C6. This step will be aided if you have a receiver that covers the same band and has capability for
receiving CW signals.
As the Easy receiver is a direct conversion design, its oscillator runs continuously and can be heard on any nearby
receiver. In this case, an antenna lead connected to the nearby receiver can be placed near the Easy Rx board and
you will hear a tone on the receiver corresponding to the local oscillator frequency of the Easy Rx.
To adjust C6, ideally you should use a plastic tool. However, if the trim-cap is installed correctly, (with the flat side
toward C ) the part you are touching is grounded and therefore, a small metallic screwdriver will be OK to use.
If using a receiver, tune it to a frequency such as 7.02 or other frequency on which you want the Easy Rx
reception range to be centered. Place R2 (the tuning knob on the left) to the middle of its range and then turn C6
slowly. You should hear a tone as the local oscillator of the Easy Rx moves across your other receiver. You will
need to turn very slowly and listen carefully as it may move quickly across the desired frequency.
Once you hear a tone on your receiver, stop adjusting C6 and you should hear a steady tone in your other receiver.
You can now connect an external antenna to the Easy Rx and use R2 to tune around. If the band is active, you
should hear some CW signals.
To set the lower range to a desired frequency, rotate the tuning control (R2) fully counterclockwise. This will place
it at the lowest frequency. Then using your external receiver set to the lowest frequency you want to use (such as
7.00 MHz for 40 meters) adjust C6 until you hear the Easy Receiver oscillator as a tone in your receiver. Turning
R2 clockwise will move up in frequency and you should be able to tune up to approximately 7.07 MHz with R2
fully clockwise.
A crystal controlled transmitter can also be used as a signal source for setting the frequency of the Easy Rx. To do
this, you would simply activate the transmitter, preferably into a dummy load so not to cause interference to
others. With a short wire or antenna connected to the Easy RX, set R 2 to the middle of its range and tune C6
while listening for the transmitter tone.
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roubleshooting
The easy RX is designed to be a simple kit to build and to use. However, occasionally, problems may happen. In
our experience, these are often soldering issues (shorts or cold solder joints) or component misplacement Here
are a few things to check if the kit does not function as it should.
1. Verify component placement, including resistors and capacitors
2. Inspect all solder joints with a magnifying glass, looking particularly for any that may have small whisker shorts
or which look dull and blotchy indicating a cold solder joint.
2. Verify orientation of the two ICs in their sockets. One end of the sockets will have a notch and that should be on
the same end as the notch in the IC package as well as a dot or other marking for pin 1 of the IC. See the photo on
page 3 and diagram on page 7 for examples of proper orientation.
3. Check for correct DC voltages to ground at the following points in the circuit:
-Right side of JP2- should be equal to power supply voltages
-Band end of D3- should be equal to power supply minus approximately 0.7V
-Pins 8 of IC1- should be approximately 6.2V
Pin 6 of IC2 -should be equal to power supply minus approximately 0.7V
If the Easy RX only makes a low level HISS in the speaker or headphones, check the local oscillator operation by
placing it near another receiver and listening for the Easy RX local Oscillator. Tune C6 if needed to locate the
oscillator in the second Receivers pass band. If there is no oscillator signal then carefully check the circuit around
the IC1, NE602/612, to be sure the parts are correct and properly soldered.
If during tune up the local oscillator could be heard in the second RX but the Easy RX has no output from the
speaker/headphones then first touch the junction of R6/C16 the speaker should make a 60 HZ humming sound. If
this happens then check the parts and soldering around the volume control. If there is no HUM then check the
parts and soldering around IC2, LM386.
If the receiver is functioning and connected to a good antenna, you should be able to hear CW signals when tuning
across the band. You will note that each signal will appear twice as you tune. This is expected for a direct
conversion receiver as it will hear the signal on both sides of the center frequency.
As you tune up in frequency and hear a signal, you will hear the signal decrease in frequency, go through zero and
then increase in frequency again. Again, this is as expected for a DC receiver.
We hope you enjoy your Easy RX kit!
If you have any questions, or experience problems with your kit, please contact us at [email protected] and
we will be happy to assist you.
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Schematic
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