MFJ MFJ-9315 Instructions for use

EF) cub
QRP CW Transceiver
Models: MFJ-9315/17/20/30/40/80
CONSTRUCTION MANUAL
CAUTION: Read All Instructions Before Operating Equipment
MFJ ENTERPRISES, INC.
300 Industrial Park Road
Starkville, MS 39759 USA
Tel: [phone] Fax: [phone]
VERSION 2A COPYRIGHT © 2000 MFJ ENTERPRISES, INC. |

Return Policy on Kits When Not Purchased Directly From MFJ Enterprises, Inc.: Before
continuing any further with your MFJ kit check with your Dealer about their return policy. If
your Dealer allows returns, your kit must be returned before you begin construction.
Return Policy on Kits When Purchased Directly From MFJ Enterprises, Inc.: Your MFJ
kit may be returned to the factory in its pre-assembled condition only. The reason for this
stipulation is, once you begin installing and soldering parts, you essentially take over the role of
the device's manufacturer. From this point on, neither MFJ nor its dealers can reasonably
held accountable for the quality or the outcome of your work. Because of this, MFJ cannot
accept return of any kit-in-progress or completed work as a warranty item for any reason
whatsoever. If you are a new or inexperienced kit builder, we urge you to read the manual
carefully and determine whether or not you're ready to take on the job. If you wish to change
your mind and return your kit, you may--but you must do it before you begin construction, and
within ten (10) working days of the time it arrives.
MF J Enterprises, Inc. Warrants: Your kit contains each item specified in the parts list.
Missing Parts: If you determine, during your pre-construction inventory, that any part is
missing, please contact MFJ and we'll send the missing item to you free of charge. However,
before you contact MFI, please look carefully to confirm you haven't misread the marking on
one of the other items provided with the kit. Also, make certain an alternative part hasn't been
substituted for the item you're missing. Ifa specific part is no longer available, or if Engineering
has determined that an alternative component is more suitable, MFJ reserves the right to make
substitutions at any time. In most cases, these changes will be clearly noted in an addendum to
the manual. |
Defective Parts: Today's electronic parts are physically and electrically resilient, and defective
components are rare. However, if you discover an item during your pre-construction inventory
that's obviously broken or unserviceable, we'll replace it. Just return the part to MFJ at the
address below accompanied with an explanation. Upon receipt, we'll test it. If it's defective and
appears unused, we'll ship you a new one right away at no charge.
Missing or Defective Parts After You Begin Assembly: Parts and materials lost or damaged
after construction begins are not covered under the terms of this warranty. However, most
parts supplied with MFJ kits are relatively inexpensive and MFJ can replace them for a
reasonable charge. Simply contact the factory with a complete description. We'll process your
order quickly and get you back on track.
Factory Repair After You Begin Assembly: Kits-in progress and completed kits are
specifically excluded from coverage by the MFJ warranty. However, as a service to
customers, technicians are available to evaluate and repair malfunctioning kits for a minimum
service fee of $18.00 (4 hour rate) plus $7.00 shipping and handling (prices subject to change).
To qualify for repair service, your kit must be fully completed, unmodified, and the printed
circuit board assembled using rosin-core solder. In the event your repair will require more than
an hour to fix (or $36.00, subject to change), our technicians will contact you in advance by
telephone before performing the work. Defective units should be shipped prepaid to:
MF] Enterprises, Inc.
300 Industrial Park Road
Starkville, MS 39759
When shipping, pack your kit well and include the minimum payment plus shipping and
handling charges ($25.00 total). No work can be performed without pre-payment. Also,
provide a valid UPS return address and a day time phone number where you may be reached.

MFJ cub ORP CW Transceiver Construction Manual
INTRODUCTION
This manual contains the information you need to build your kit. The cub is
unique because it uses both surface-mount (SMD) and conventional electronic
components. From an electrical standpoint, surface-mount circuitry has many
advantages. However, SMD parts are too tiny for most people to handle in a
kit. MFJ solves this problem by pre-installing many of the kit's parts using our
automated SMD assembly equipment. These machines accomplish--in a matter
of minutes--what would take a trained assembler an entire day to complete by
hand. Then, once the SMD work is complete, we hand the project over to you.
You'll begin by inventorying the parts packages to ensure everything you need
is included. Parts are grouped into two categories. Some are generic
components such as switches, jacks, controls, trimmers, and the PA transistor.
The rest are frequency-determining coils, capacitors, and crystals that
determine the band of operation. To complete your cub, you'll need only
conventional bench tools and general knowledge of through-hole pc-
construction methods. To help you along, this manual provides step-by-step —
guidance for each operation. When construction is complete, it walks you
inspection, testing, and tuning. Finally, it shows you how to install the case
and add the finishing touches. In a few short hours, you'll be taking to the
airwaves with your new radio.
BEFORE YOU START BUILDING
Work Area: You'll need a clean, smooth, and well-lighted area--a place where
you can handle small parts without losing them. A sheet of white poster board
makes a good construction surface. Well-diffused overhead lighting and a
supplemental high-intensity desk lamp provide strong lighting for close-up
work. Be sure to keep the work area free of clutter and discarded wire ends.
Tools and Supplies: Here's a checklist of the tools and supplies you'll need:
O Low-wattage soldering iron with a narrow chisel tip or conical tip.
O Soldering iron holder with a moistened cleaning sponge.
CO 60/40 or 63/37 alloy solder .02"-.032" in diameter, rosin or "no-clean"
flux.
Small needle-nose pliers or a surgical hemostat.
Diagonal or "nippy" wire cutters.
Solder sucker or desoldering braid.
Magnifying glass. Ood a

a ee a ee aI RT ee TE
MFJ cub ORP CW Transceiver Construction Manual
These items are needed for testing and tune-up:
CO QRP-type RF power meter or VSWR bridge (or 5mm LED, any color).
[ 50 ohm dummy load (or two 1 watt 100 ohm carbon-film resistors).
O Telegraph key or keyer with 3.5mm plug installed.
O
8-40 ohm headphones or extension speaker with 3.5mm stereo plug
installed.
O 13.8V @ 400 mA regulated DC power source.
[1 Low VSWR antenna cut for your radio's band of operation.
O Low level signal source tuned to the radio's band of operation.
O Kit of insulated tuning tools.
Avoiding Errors: Experience shows there are four common mistakes builders
make. Avoid these, and your kit should work on the first try!
1. Installing Wrong Part: Pre-sort components before you begin and double-
check the numbers stamped on each part before installing.
2. Reversing Polarized or Keyed Parts: ICs, transistors, diodes, and
electrolytic capacitors must be installed only one way. Always double-check
before inserting!
3. Bad Solder Connections: Constantly inspect for cold solder joints or
solder bridges between pads while you work.
4. Omitting a Part: Check off each step in the manual as you complete it.
Soldering Tips: Cleanliness and good heat distribution are the secrets of
professional soldering. Before you install each part, inspect leads for oxidation.
If the surface looks dull, burnish it with a pencil eraser or glass-fiber brush
(available at Radio Shack). When soldering, let the iron tip contact both lead
and pad for about one second before feeding solder. Solder should flow
smoothly into platethrough holes, wetting all exposed surfaces. Apply solder
sparingly and avoid touching solder wire directly to the hot iron tip.
Desoldering Tips: If you make a mistake and need to remove a part, grasp the
component lead with hemostats and heat the pad from the opposite side. Pull
gently--the lead should come out (repeat for the other lead). If solder fills in
behind, reheat the pad and extract it with a solder-sucker or solder wick. Parts
damaged during extraction should be replaced (multilayer capacitors are
especially vulnerable to removal damage).

MEFJ cub QRP CW Transceiver Construction Manual
PARTS INVENTORY
After opening you MFJ cub box, check for the following.
1 - Printed circuit board (surface mount parts installed) | P/N: 40-9300-1SM
1 - 2.1mm power plug with cable P/N: 620-8321
1 - Metal chassis P/N: 800-9300
1 - Metal top P/N: 804-9300
1 - Construction manual P/N: 925-9300-1
1 - Operation manual P/N: 925-9300-2
3 - Parts bag
The parts list (bagged parts) is presented in three parts. First, you'll identify
and inventory generic parts--items common to all cub transceivers. Next,
you'll inventory frequency-determining parts--those items that determine band
coverage. Then, you’ll inventory the parts for installing and putting the final
touches on your enclosure. Identify each part carefully, consulting the manual
for color codes or special markings. When sorting capacitors, look for a value
or number code printed on the body:
Disc Ceramic Polystyrene [——— Multilayer ———
(4.7 pF) (680 pF) Q7pF) (270pF) (.001 uF)
=
Use the following inventory list to arrange parts for rapid identification during
construction. If you discover a missing or damaged item, refer to the warranty
section for replacement instructions. Begin by unpacking the kit's generic
parts.

MFI cub ORP CW Transceiver | Construction Manual
2N5109 transistor
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62-9320
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Next, find the band-determining parts and check contents against the
appropriate parts list:
12 MHz crystal
#22 enamel wire, 24” length

MEFJ cub ORP CW Transceiver Construction Manual
Designation |
3.3} | 1 C13,C46 200-00033-1_
| O | 1 | 10 pF multilayer capacitor 220-0010
}O |] 1 [15 [c44, Cs: 220-0015
ioe ame a yer cal 220-0022
| O | 2 | 56 pF multilayer capacitor C45,C47 220-0056
220-0082
220-0100
220-0150
C53,C55,C56,C57 | 220-0180
220-0270
220-0560
| | 470 pF polystrerene capacitor 240-0470
| 2 | 1.5uHmoldedinductor | L8, 401-3150
402-3401
| O | 2 | T37-6toroidform ‘for L10,L11 403-1437
PO [ 5 [10MHzcrystal sss: 1, Y2,Y3,Y4,Y5 | 405-0065
| O | 1 | #22 enamel wire, 24” length | forL10,L11__—|: 870-3022R
|
io ©
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FJ P/N
00-00033-1
EER i.
ogee. 1 Sa
T37-2 toroid form for L10,L11
10 MHz crystal 1,Y2,Y3,¥4,Y5 | 405-0065

MFJ cub ORP CW Transceiver Construction Manual
| O | 2 [| 82 pF multilayer capacitor
| O | 2 | 100 pF multilayer capacitor
1 12 ilaye I
0 pF multilayer capacitor
| 470 pF multilayer capacitor | C53,C55,C56,C57 | 220-0470 __|
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820 pF multilayer capacitor |C15 | 220-0820
|__| 470 pF polystrerene capacitor 240-0470
L
680 pF 7 e capaci
| 3.3uH molded inductor | L8_ | 401-3330
| 4.7uH molded inductor ss [LO 401-3470
|
403-1037
|
| 870-3024R _|
;

MFJ cub QRP CW Transceiver Construction Manual
eoete
220-1220
|
| 4 ([68uHslug-tunedcol [| L1,L2,L6,L7___— | 402-3406
403-1037 __|
#24 enamel wire, 36” length
654-0500
Self-tapping screw (black 656S-0375B-A
| O | 2 | 4-40x%" hex spacer 716B-0250
4-40 KEP nuts 705-0440-K
%” x %" knob 760-0023
1" x %” knob 760-0035
Panel nut for 16mm pot 705-7075
Panel washer for 16mm pot 710-2550

MFJ cub QRP CW Transceiver Construction Manual
PARTS PLACEMENT DIAGRAM
+
in
= Bagge Mele
Ses
CG BIPEE
C=) [5] [8] cm ;
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P/N: 862-9320 Rev e
STEP-BY-STEP ASSEMBLY
Terminology: When you read the term install, this means to locate, identify,
dress the leads, and insert the part into its mounting holes on the PC board.
Once a component is mounted, bend each lead over and use sharp side-cutters
to clip off the excess. Make sure lead ends don't touch other pads, tracks, or the
groundplane surface (see below).
The term solder means to solder the part's leads in place, inspect for flaws or
solder
bridges,
and
nip
off
any
protruding
lead
or
pin
with
a
sharp
pair
of
side
cutters.
All
solder
connections
will
be
made
on
the
bottom
(groundplane)
side
of the pc board.
8

MFJ cub QRP CW Transceiver Construction Manual
Generic Parts
Begin by finding two (2) 3.5mm stereo phone jacks. When installing, make
sure the plastic body is seated flush with the pc board.
O Install a 3.5mm phone jack at J2 and solder all 5 pins.
1 Install a 3.5mm phone jack at J4 and solder all pins.
O Locate the 2.1mm coaxial power jack. Install at J1 and twist all tabs 45
degrees with pliers to secure in place. Solder all 3 tabs.
O Locate the RCA antenna jack. Seat firmly at J3 and solder all 4 tabs.
O Install the 2P2T mini power switch at SW1 and solder all 6 pins.
This may be a tight fit — work pins in slowly.
Find two potentiometers (volume and tune), and use the detail below when
installing:
set aside for later
installation (if required)
Remove hardware and
BS
Install in front set of holes
O Identify the 500 ohm pot (B500). Install at R14 and solder all 3 tabs.
O Identify the 10K pot (B10K). Install at R4 and solder all 3 tabs.
Find two (2) 60 pF MuRata trimcaps (orange plastic body).
CO Install a 60 pF trimcap at C27 (flat side either way) and solder.
O Install a 60 pF trimcap at C40 (flat side either way) and solder.

MFJ cub QRP CW Transceiver Construction Manual
Locate the 10K 6mm trimpot (marked 102). Install at R19 and solder all 3
tabs.
O Locate the red LED. Following the detail provided below, mount at CR1.
Note that CR1 is a polarized part. Orient so the shorter of the two leads
(cathode) is toward the corner of the board (ground). When positioned as
shown, solder.
E
Shorter lead
(ground) &£
Press leads flat to pc board
en
oe
Th
LED base butted against edge of pc board
O Locate the MV2104 varactor diode (looks like a plastic transistor with two
leads). Install at D2 with the flat side toward the front of the pc board.
Solder.
Locate the 3.5 uH shielded slug-tuned VFO coil. Inspect to make sure all
pins and tabs are straight. Install at L3 and solder all pins and tabs.
Locate the 2N5109 PA transistor. The cub normally delivers 1.5 - 2.0 watts RF
output from a 13.8V power source using this device (1 watt on 15 meters). If
you wish to substitute a more powerful PA transistor, check the supplemental
instructions following this step. If not, inspect the 2N5109 and straighten any
bent leads.
10

MFJ cub QORP CW Transceiver Construction Manual
C1) Install Q7 so its flange is elevated about .1" above the pc board, as shown.
Solder in place. The clip-on heatsink will be installed later, after the
remaining parts are mounted.
2N5109
ecers: 2.9.6 9 2.6.9 0% 9.6.0 0. # 9.
AYU RAREX DOS CMTS RET E ES oY O REE BOL eee,
ee SAC CI ITO Te
RNa aaa ewe wie
Alternative PA Transistors: A 2N3553 (not supplied) may be substituted
directly for the 2N5109. This device typically delivers up to 50% more output.
A second substitute, the Motorola MRF-237, may deliver even more output--up
to 4 watts on 20 meters. The MRF-237 is not a direct replacement. When
installing, the case must be rotated 180-degrees and its base lead brought across
to the base-connection pad (see below). Note that MFJ cannot accept
responsibility for the outcome of any customer modification.
2N5109 B
2N3866 _-/ ‘ 3
2N4427 MRF-237 E(o i
2N3553. BR
This concludes installation of the generic parts provided in your kit. Take a
break and double-check your work before beginning installation of the
frequency-determining parts.
MFJ-9315 15 Meter Transceiver
Locate two (2) 3.3 pF disc ceramic capacitors marked 339 or 3.3.
O Install a 3.3 pF capacitor at C13 and solder.
C} Install a 3.3 pF capacitor at C46 and solder.
The next group of capacitors you'll install are multilayer. Forcing or
overheating the leads of multilayer caps may damage them, so use care during
i]

MFJ cub ORP CW T. ransceiver Construction Manual
installation or removal. If necessary, pre-shape leads to the correct spacing
before inserting.
Incorrect
_[Incorrect
Correct
Find two (2) 10 pF multilayer caps (marked 10 or 100).
C Install 10 pF at C9 and solder.
MO Install 10 pF at C44 and solder.
C) Locate a 18 pF multilayer cap (marked 18 or 180). Install at C48 and
solder.
Find two (2) 47 pF multilayer caps (47 or 470).
O Install 47 pF at C45 and solder.
O Install 47 pF at C47 and solder.
O Locate a 68 pF multilayer cap (68 or 680). Install at C14 and solder.
O Locate a 82 pF multilayer cap (82 or 820). Install at C52 and solder.
Find two (2) 100 pF multilayer caps (101).
O Install 100 pF at C11 and solder.
[C) Install 100 pF at C12 and solder.
Find five (5) 150 pF multilayer caps (151).
Install 150 pF at C6 and solder.
Install 150 pF at C53 and solder.
Install 150 pF at C55 and solder.
Install 150 pF at C56 and solder.
Install 150 pF at C57 and solder.
Locate a 470 pF multilayer cap. Install at C15 and solder.
OoOd dad Oo
[1 Locate a 330 pF polystyrene capacitor (silver in color, 330J stamped on the
body). Install at C7 and solder in place.
This completes capacitor installation (C62 is not used with the 15 meter kit).
12

MFJ cub ORP C W Transceiver Construction Manual
Find four (4) shielded slug-tuned coils (1.2 uH). Inspect each coil and
straighten bent soldering tabs or pins.
90 POOR?
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Install a shielded coil at L1. Soldering all five (5) pins and both tabs.
Install a shielded coil at L2 and solder.
Install a shielded coil at L6 and solder.
Install a shielded coil at L7 and solder.
Find two (2) 1.5 uH molded chokes (brown-green-gold-silver).
CO Install a 1.5 uH choke at L8.
C Install a 1.5 uH choke at L9.
Find two (2) T37-6 toroid forms (doughnut-shaped, .37" in diameter, black
with yellow-paint color coding). Also, find the length of #22 enameled wire
and cut into two equal lengths. L10 and L11 are hand-wound on toroid forms
prior to installation. When winding toroids, remember the number of turns are
counted inside the form. Pull each turn up tight before starting the next. If the
coil is wound loosely, inductance may be too high, compromising transmitter
performance. After winding, scrape both leads with a hobby knife to remove
insulation and tin with solder.
ODod a
Count turns on inside of form.
Pull each turn tight before winding the next.
eee
Ly
Tin
leads
with
solder
before
installing.
[1 Wind 10 turns of #22 enameled wire onto a T37-6 toroid form and prep
leads.
C) Install at L10 and solder.
Wind 10 turns of #22 on the second T37-6 toroid form and prep.
13

MFJ cub QRP CW Transceiver Construction Manual
Install at L11 and solder.
Next, find the five (5) 12 MHz crystals (12.000). When installing, do not press
the can tightly against the pc board--this could short mounting pads to the
metal case. Leave a small air-gap between the base and pc board.
%
aatetere:
aarerarss
Correct == Incorrect
revecete’
‘aiererets
etatets 5
RRAAQAN nN
Install a 12 MHz crystal at Y1.
Install a 12 MHz crystal at Y2.
Install a 12 MHz crystal at Y3.
Install a 12 MHz crystal at Y4.
Install a 12 MHz crystal at Y5.
OoOd da Oo
This concludes assembly of the MFJ-9315 board. Proceed to the Testing and
Alignment section.
MFJ-9317 17 Meter Transceiver
Locate two (2) 3.3 pF disc ceramic capacitors marked 339 or 3.3.
O Install a 3.3 pF capacitor at C13 and solder.
1) Install a 3.3 pF capacitor at C46 and solder.
The next group of capacitors you'll install are multilayer. Forcing or
overheating the leads of multilayer caps may damage them, so use care during
installation or removal. If necessary, pre-shape leads to the correct spacing
before inserting.
Incorrect
Incorrect
Correct
[ Locate a 10 pF multilayer cap (marked 10 or 100). Install at C9 and
solder.
[ Locate a 15 pF multilayer cap (marked 15 or 150). Install at C44 and
solder.
14

MFI cub ORP CW Transceiver. —~=~=~—~S«Sonstruction Maar’
O Locate a 22 pF multilayer cap (marked 22 or 220). Install at C48 and
solder.
Find two (2) 56 pF multilayer caps (56 or 560).
O Install 56 pF at C45 and solder.
C) Install 56 pF at C47 and solder.
O Locate a 82 pF multilayer cap (82 or 820). Install at C14 and solder.
Find two (2) 100 pF multilayer caps (101).
[) Install 100 pF at C11 and solder.
O Install 100 pF at C12 and solder.
[ Locate a 150 pF multilayer cap (151). Install at C6 and solder.
Find five (4) 180 pF multilayer caps (181).
Install 180 pF at C53 and solder.
Install 180 pF at C55 and solder.
Install 180 pF at C56 and solder.
Install 180 pF at C57 and solder.
Locate a 270 pF multilayer cap (271). Install at C52 and solder.
Locate a 560 pF multilayer cap (561). Install at C15 and solder.
ODoOdacdnca og
Locate a 470 pF polystyrene capacitor (silver in color, 470J stamped on the
body). Install at C7 and solder in place.
This completes capacitor installation (C62 is not used with the 17 meter kit).
Find four (4) shielded slug-tuned coils (1.2 uH). Examine each coil and
straighten soldering tabs or bent pins.
[1 Install a 1.2 uH shielded coil at L1. Solder all five (5) pins and both tabs.
Install a 1.2 uH shielded coil at L2 and solder.
C) Install a 1.2 uH shielded coil at L6 and solder.
15

MFJ cub QRP CW Transceiver Construction Manual
O Install a 1.2 uH shielded coil at L7 and solder.
Find two (2) 1.5 wH molded chokes (brown-green-gold-silver).
C Install a 1.5 uH choke at L8.
Install a 1.5 uH choke at L9.
Find two (2) T37-6 toroid forms (doughnut-shaped, .37" in diameter, black
with yellow-paint color coding). Also, find the length of #22 enameled wire
and cut into two equal lengths. L10 and L11 are hand-wound on toroid forms
prior to installation. When winding toroids, remember the number of turns are
counted inside the form. Pull each turn up tight before starting the next. If the
coil is wound loosely, inductance may be too high, compromising transmitter
performance. After winding, scrape both leads with a hobby knife to remove
insulation and tin with solder. Following these instructions:
Count turns on inside of form.
Pull each turn tight before winding the next.
~ Tin leads with solder before installing.
O Wind 11 turns of #22 enameled wire onto a T37-6 toroid form and prep
leads.
C Install at L10 and solder.
C Wind 11 turns of #22 on the second T37-6 toroid form and prep leads.
C Install at L11 and solder.
Next, find the five (5) 10 MHz crystals (10.000). When installing crystals, do
not press the can tightly against the pc board--this could short mounting pads to
the metal case. Leave a small air-gap between the base and pc board.
aces,
se ceceges
oe tatete’
Correct <4 Incorrect
SO e__°__ _T__P__lJo
C1 Install a 10-MHz crystal at Y1.
Install a 10-MHz crystal at Y2.
C) Install a 10-MHz crystal at Y3.
16

MFJ cub QRP CW Transceiver Construction Manual
O Install a 10-MHz crystal at Y4.
O Install a 10-MHz crystal at Y5.
This concludes assembly of the MFJ-9317 board. Proceed to the Testing and
Alignment section.
MFJ-9320 20 Meter Transceiver
Locate two (2) 3.3 pF disc ceramic capacitors marked 339 or 3.3.
C Install a 3.3 pF capacitor at C13 and solder.
O Install a 3.3 pF capacitor at C46 and solder.
The next group of capacitors you'll install are multilayer. Forcing or
overheating the leads of multilayer caps may damage them, so use care during
installation or removal. If necessary, pre-shape leads to the correct spacing
before inserting.
Incorrect
Incorrect
Correct
Find two (2) 15 pF multilayer caps (marked 15 or 150).
C) Install 15 pF at C44 and solder.
Install 15 pF at C48 and solder.
Find two (2) 68 pF multilayer caps (marked 68 or 680).
O Install 68 pF at C45 and solder.
Install 68 pF at C47 and solder.
1 Locate a 100 pF multilayer cap (marked 101). Install at C14 and solder.
Find two (2) 150 pF multilayer caps (marked 151).
Install 150 pF at C11 and solder.
C) Install 150 pF at C12 and solder.
Find four (4) 220 pF multilayer caps (marked 221).
C) Install 220 pF at C53 and solder.
O Install 220 pF at C55 and solder.
17

MEFJ cub QORP CW Transceiver Construction Manual
C) Install 220 pF at C56 and solder.
C1) Install 220 pF at C57 and solder.
Find two (2) 330 pF multilayer caps (marked 331).
Install 330 pF at C9 and solder).
O Install 330 pF at C52 and solder).
[C1 Locate a 680 pF multilayer cap (marked 681). Install at C15 and solder.
Find two 680 pF polystyrene type capacitor (silver in color, coated with clear
plastic, 680J stamped on the body).
1 Install 680 pF (polystyrene) at C7 and solder in place.
C Install 680 pF (polystyrene) at C6, standing on end--as illustrated below:
.
C6
Ca
This completes capacitor installation (C62 is not used with the 20 meter kit).
Find four (4) 1.5 uH shielded slug-tuned coils. Inspect each and straighten any
bent tabs or pins.
Install a shielded coil at L1, soldering both tabs and all 5 pins.
Install a shielded coil at L2, and solder.
Install a shielded coil at L6 and solder.
Install a shielded coil at L7 and solder.
Find two (2) 1.8 uH molded chokes (brown-gray-gold-silver).
1) Install a 1.8 uH choke at L8 and solder.
1 Install a 1.8 uH choke at L9 and solder.
Find two (2) T37-2 toroid forms (doughnut-shaped, .37" in diameter, black
with red paint color coding). Also, find the length of #22 enameled wire and
OOO dQ
18