Return Policy on Kits When Not Purchased Directly From Vectronics: Before continuing
any further with your VEC 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 Vectronics: Your VEC kit may be
returned to the factory in its pre-assembled condition only. The reason for this stipulation is,
once you begin i nsta lli ng a nd sol deri ng pa rt s, you essenti al ly tak e over the rol e of the devic e's
manufacturer . From this point on, neither Vect ronics nor its dea lers can reas onably be held
accountab le for the qua lity or the outcome of your work. Because of this, Vectronics 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 b uilder, we urge you to read the manual
carefully a nd determine whether or not you're r eady to tak e on the job. If you wish to c hange
your mind and return your ki t, you may--b ut you must do i t before you begin c ons tr uc ti on, a nd
within ten (10) working days of the time it arrives.
Vectronics 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 Vectronics and we'll send the missing item to you free of charge.
However, before you contact Vect ronic s, please look carefully to c onf ir m you haven't misr ea d
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. If a specific part is no longer
available, or if Engineering has determined that an alternative component is more suitable,
Vectronics 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 a re r a re. However, if you disc over a n it em duri ng your pr e- c onst r uct i on
inventory that's obviously broken or unserviceable, we'll replace it. Just return the part to
Vectronics at the address below accompanied with an explanation. Upon receipt, we'll test it.
If it's defec tive and appear s 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 VEC kits are relatively inexpensive and Vectronics 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 trac k.
Factory Repair After You Begin Assembly: Kits-in progress and completed kits are
specifically excluded from coverage by the Vectronics warranty. However, as a service to
customers, tec hnicia ns ar e availa ble t o evaluate a nd repai r malf unctioni ng kits for a minimum
service fee of $18.00 (½ 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 fi x (or $36.00, subject to change), our technicians will contact you in
advance by telephone b efore p erforming t he work. Def ective unit s should b e shipp ed prep aid
to:
Vectronics
1007 HWY 25 South
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 a nd a day time phone number where you may be reac hed.
VEC-422K Owner's Manual SCA Decoder Kit
INTRODUCTION
Hidden in many standard FM broadcast signals is a host of very interesting
programming—and you can listen in for free! You’ll find commercial free
background music that the restaurants and hotels subscribe to, all news
programs, weather reports, stock quotes, digital data, ethnic programs in
different la nguages, rea ding services for the blind , and much, much more. T his
programming is carrie d by hidden sub carrier s on the FM signal , using the VEC422K SCA Decoder allows you to unlock and monitor the subcarrier
programming!
The decoder connects to your FM receiver or tuner using one simple connection!
Many receivers already have SCA output jacks. If not, we’ll give you some
simple directions for hooking up your VEC-422K to almost any FM broadcast
receiver or tuner! The heart of the VEC-422K is a special FSK decoder chip.
No alignment is needed, and construction is quick and simple thanks to the
VECTRONICS professional solder masked and screened PC board. The SCA
decoder features an on-board audio amplifier to drive headphones or a speaker,
or a line-level output to feed your HI-FI system amplifier. The VEC-422K tunes
subcarrier frequencies from 50 to 100kHz. Learn how subcarriers work, and
how they are decoded.
TOOLS AND SUPPLIES
Construction Area:
area where you can easily organize and handle small parts without losing them.
An inexpensive sheet of white poster board makes an excellent construction
surface and provides protection for the underlying table or desk. Well-diffused
overhead lighting is a plus, and a supplemental high-intensity desk lamp is
especially helpful for close-up work. Safety is always important! Be sure to use
a suitable high-temperature stand for your soldering iron, and keep the work area
free of combustible clutter.
Universal Kit-building Tools:
additional items for completion, virtually all construction projects require a work
area outfitted with the following tools and supplies:
!"
30-60 Watt Soldering Iron (temperature-controlled preferred)
!"
High-temperature Iron Holder with Moist Cleaning Sponge.
Kit construction requires a clean, smooth, and well-lighted
Although your particular kit may require
1
VEC-422K Owner's Manual SCA Decoder Kit
!
Solder Sucker (squeeze bulb or vacuum pump type), or Desoldering Braid
!
Bright Desk Lamp
!
Magnifying Glass
BEFORE YOU START BUILDING
Experience shows there are four common mistakes builders commonly make.
Avoid these, and your kit will probably work on the first try!
1. Installing the Wrong Part:
and a 10K resistor may look almost the same, but they may act very
differently in an electronic circuit! Same for capacitors--a device marked
102 (or .001 uF) may have very different operating characteristics from one
marked 103 (or .01uF).
2. Installing Parts Backwards:
capacitors to make sure the positive (+) lead goes in the (+) hole on the
circuit board. Transistors have a flat side or emitter tab to help you identify
the correct mounting position. ICs have a notch or dot at one end indicating
the correct direction of insertion. Diodes have a banded end indicating
correct polarity. Always double-check--especially before applying power to
the circuit!
3. Faulty Solder Connections:
bridges. Cold solder joints happen when you don't fully heat the connection-or when metallic corrosion and oxide contaminate a component lead or pad.
Solder bridges form when a trail of excess solder shorts pads or tracks
together (see Solder Tips below).
4. Omitting or Misreading a Part:
Always double-check to make sure you completed each step in an assembly
sequence.
Soldering Tips:
professional soldering. Before you install and solder each part, inspect leads or
pins for oxidation. If the metal surface is dull, sand with fine emery paper until
shiny. Also, clean the oxidation and excess solder from the soldering iron tip to
ensure maximum heat transfer. Allow the tip of your iron to contact both the
lead and pad for about one second (count "one-thousand-one") before
solder to the connection. Surfaces must become hot enough for solder to flow smoothly. Feed solder to the opposite side of the lead from your iron tip--solder
will wick around the lead toward the tip, wetting all exposed surfaces.
Cleanliness and good heat distribution are the two secrets of
It always pays to double-check each step. A 1K
Always check the polarity of electrolytic
Inspect for cold-solder joints and solder
This is easier to do than you might think!
feeding
Desoldering Tips:
these instructions carefully! First, grasp the component with hemostats or
2
If you make a mistake and need to remove a part, follow
VEC-422K Owner's Manual SCA Decoder Kit
needle-nose pliers. Heat the pad beneath the lead you intend to extract, and pull
gently. The lead should come out. Repeat for the other lead. Solder may fill in
behind the lead as you extract it—especially if you are working on a doublesided bo ard with plate-through hole s. Should this happen, try heating the pad
again and inserting a common pin into the hole. Solder won’t stick to the pin’s
chromium plating. When the pad cools, remove the pin and insert the correct
component. For ICs or multiple-pin parts, use desoldering braid to remove
excess solder before attempting to extract the part. Alternatively, a low-cost
vacuum-bulb or spring-loaded solder sucker may be used. Parts damaged or
severely overheated during extraction should be replaced rather than reinstalled.
Work Habits:
instructions and, in many cases, to perform new and unfamiliar tasks. To avoid
making needless mistakes, work for short periods when you’re fresh and alert.
Recreational construction projects are more informative and more fun when you
take your time. Enjoy!
Sorting and Reading Resistors:
a color code (shown below). You don’t have to memorize this code to work with
resistors, but you do need to understand how it works:
Kit construction requires the ability to follow detailed
The electrical value of resistors is indicated by
Resistor Color Code
Black = 0 (tens)
1st Digit
2nd Digit
Multiplier
Tolerence
(gold or silver)
When you look at a resistor, check its multiplier code first. Any resistor with a
black multiplier band falls between 10 and 99 ohms in value. Brown designates
a value between 100 and 999 ohms. Red indicates a value from 1000 to 9999
ohms, which is also expressed as 1.0K to 9.9K. An orange multiplier band
designates 10K to 99K, etc. To inventory resistors, first separate them into
groups by multiplier band (make a pile of 10s, 100s, Ks, 10Ks, etc.). Next, sort
each group by specific value (1K, 2.2K, 4.7K, etc.). This procedure makes the
inventory easier, and also makes locating specific parts more convenient later on
during construction. Some builders find it especially helpful to arrange resistors
in ascending order along a strip of double-sided tape.
Brown = 1 (hundreds)
Red = 2 (K)
Orange = 3 (10K)
Yellow = 4 (100K)
Green = 5 (1Meg)
Blue = 6
Violet = 7
Gray = 8
White = 9
Silver = 10%
Gold = 5%
This VEC kit contains molded chokes which appear, at first glance, similar to
resistors in both shape and band marking. However, a closer look will enable
you to differentiate between the two—chokes are generally larger in diameter
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VEC-422K Owner's Manual SCA Decoder Kit
and fatter at the ends than resistors. When doing your inventory, separate out
any chokes and consult the parts list for specific color-code information.
Reading Capacitors:
value identification. Instead, the value, or a 3-number code, is printed on the
body.
Value Code
10 pF = 100
100 pF = 101
1000 pF = 102
.001 uF = 102*
.01 uF = 103
.1 uF = 104
As with resistors, it’s helpful to sort capacitors by type, and then to arrange them
in ascending order of value. Small-value capacitors are characterized in pF (or
pico-Farads), while larger values are labeled in uF (or micro-Farads). The
transition from pF to uF occurs at 1000 pF (or .001 uF)*. Today, while most
monolithic (multilayer) and disc-ceramic capacitors are marked with a threenumber code, you may still find a .1 uF capacitor marked either “104” or “.1”.
For three digit codes, the first two digits indicate a numerical value, while the
last digit indicates a multiplier (same as resistors). The value is in pF; thus a
capacitor marked “104” is 100,000 pF, or .1 uF.
Electrolytic capacitors are always marked in uF. Electrolytic capacitors are
polarized devices and must be oriented correctly during installation. If you
become confused by markings on the case, remember the uncut negative lead is
slightly shorter than the positive lead.
Unlike resistors, capacitors no longer use a color code for
Electrolytic
1 uF
1uF
|
35V
|
+
-
Multilayer
(270 pF)
271
Ceramic Discs
(.001 uF) (.1 uF)
102
104
Diodes:
Always look for the banded or cathode end when installing, and follow
instructions carefully.
Transistors:
power is applied. Transistors in metal cases have a small tab near the emitter
lead to identify correct positioning. Semiconductors housed in small plastic
cases (TO-92) have an easily-identified flat side to identify mounting orientation.
Many specialized diodes and low-current voltage regulators also use this type
4
Diodes are also polarized devices that must be installed correctly.
Cathode
(shorter Lead)
Diode
If transistors are installed incorrectly, damage may result when
LED
VEC-422K Owner's Manual SCA Decoder Kit
packaging. Larger plastic transistors and voltage regulators use a case backed
with a prominent metal tab to dissipate heat (T-220). Here orientation is
indicated by the positioning of the cooling tab.
Metal Can DevicePlastic DeviceTab-cooled Device
Emitter
Flat Side
Integrated Circuits:
marking located on one end of the device. A corresponding mark is silkscreened on the PC board and printed on the kit’s parts-placement diagram. To
identify specific IC pin numbers for testing purposes, see the diagram below.
Pin numbers always start at the keyed end of the case and progress
counterclockwise around the device, as shown:
Installation
Key
Proper IC positioning is indicated by a dot or square
8 7 6 5
Installation
1 2 3 4
Pin Numbers
Metal Tab
Key
5
VEC-422K Owner's Manual SCA Decoder Kit
PARTS LIST
Your kit should contain all of the parts listed below. Please identify and
inventory each item on the checklist before you start building. If any parts are
missing or damaged, refer to the manual’s warranty section for replacement
instructions. If you can’t positively identify an unfamiliar item on the basis of
the information given, set it aside until all other items are checked off. You may
then be able to identify it by process of elimination. Finally, your kit will go
together more smoothly if parts are organized by type and arranged by value
ahead of time. Use this inventory as an opportunity to sort and arrange parts so
you can identify and find them quickly.
Resistors:
Note: The fourth color band (gold) denotes tolerance, only the three bands
determining resistance value are listed.