Vectronics VEC-1402K User Manual

IMPORTANT WARRANTY INFORMATION! PLEASE READ

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.

TABLE OF CONTENTS

Introduction.....................................................................................................2

Tools and Supplies..........................................................................................2

Before You Start Building...............................................................................3

Soldering Tips:.......................................................................................3

Desoldering Tips:...................................................................................3

Work Habits:..........................................................................................4

Sorting and Reading Resistors:...............................................................4

Reading Capacitors:................................................................................5

Diodes: ...................................................................................................5

Transistors:.............................................................................................6

Integrated Circuits:.................................................................................6

Parts List..........................................................................................................7

Parts Placement Diagram ................................................................................7

Step-By-Step Assembly...................................................................................8

PC Board Inspection:.............................................................................. 11

Testing and Alignment ....................................................................................12

Generator Method: .................................................................................12

Off-air Method: ......................................................................................13

Operating Instructions.....................................................................................13

In Case of Difficulty........................................................................................15

Preamp Stops Amplifying:......................................................................15

Cannot Align or Test Preamp:................................................................15

Voltmeter Checks:..................................................................................15

Theory of Operation and Specifications..........................................................16

Operation:...............................................................................................16

Specifications:........................................................................................16

Schematic........................................................................................................17

VEC-1402K Instruction Manual 2 Meter Pre-Amp Kit

INTRODUCTION

Now you can soup-up your 2-meter receiver or scanner with a 16-dB boost. The VEC-1402K breathes new life into "deaf" receivers and marginal antenna systems. Unlike low-cost GaAsFET preamps, this kit uses a high-quality microwave-type bipolar transistor that features exceptional low-noise performance and good immunity from damaging electrostatic discharge. A high-Q LC-tuned input filter fights overload from out-of-band signals, and careful output matching ensures efficient energy transfer into your 50-ohm feedline. In addition to covering 2-meters, the VEC-1402K can boost other frequencies in the 135-165 MHz commercial 2-way FM and WeFAX radio spectrum with only minor r etuning. Although big in pe rformance, the pre amps are small in size (1" x 1-1/2"), and you can power them locally or remotely at the antenna with 9-14 volts dc.

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, while providing protection for the underlying table or desk. Welldiffused overhead lighting is a plus, and a supplemental high-intensity desk lamp will prove especially helpful for close-up work. Safety is an important consideration. 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 to complete, virtually all construction projects require a work area outfitted with the following tools and supplies:

30 to 60 Watt Soldering Iron

High-temperature Iron Holder with Moist Cleaning Sponge

Rosin-core Solder (thin wire-size preferred)

Needle Nose Pliers or Surgical Hemostats

Diagonal Cutters or "Nippy Cutters"

Solder Sucker, Vacuum Pump, or Desoldering Braid

Bright Desk Lamp

Magnifying Glass

Special tool for this kit:

Kit construction requires a clean, smooth, and well-lighted

Although your particular kit may require

Hex-head insulated tuning tool.

BEFORE YOU START BUILDING

VEC-1402K Instruction Manual 2 Meter Pre-Amp Kit

Experience shows there are four common mistakes builders make. Avoid these, and your kit will probably work on the first try! Here's what they are:

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 Soldering Tips below).

4. Omitting or Misreading a Part:

Always double-check to make sure you completed each step in an assembly sequence.

Soldering Tips:

Cleanliness and good heat distribution are the two secrets of 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 feeding 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. Apply solder sparingly, and do not touch solder directly to the hot iron tip to promote rapid melting.

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!

Desoldering Tips:

VEC-1402K Instruction Manual 2 Meter Pre-Amp Kit

If you make a mistake and need to remove a part, follow these instructions carefully! First, grasp the component with a pair of hemostats or 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 double-sided board with plate-through ho les. Should this happen, try heating the p ad 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 multi-pin parts, use desoldering braid to remove excess solder before attempting to extract the part. Alternatively, a low-cost vacuum-bulb or springloaded solder sucker may be used. Parts damaged or severely overheated during extraction should be replaced rather than reinstalled.

Work Habits:

Kit construction requires the ability to follow detailed 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:

The electrical value of resistors is indicated by 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:

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 sort and 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

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%

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