Palstar AT4K User manual

Palstar Incorporated
9676 N. Looney Rd.,
Piqua, OH 45356 USA
Customer Service and Sales Telephone:
1-800-773-7931
Fax:
1-937-773-8003
Email:
in [email protected]
VER 1.5 2008_04
© Copyright 2008 Palstar Inc.
Printed in the U.S.A.
AT4K 2500 Watt Antenna Tuner
Owner’s Manual

1-800-773-7931 W WW.PALST AR . CO M
2 Important Safeguards
WARNING: TO PREVENT FIRE OR
ELECTRICAL SHOCK DO NOT
EXPOSE TO RAIN OR MOISTURE
1. Read Instructions All the safety and
operating instructions should be read before
the appliance is operated.
2. Retain Instructions The safety and
operating instructions should be retained for
future reference.
3. Heed Warnings All warnings on the
appliance should be adhered to.
4. Follow Instructions All operating and
use instructions should be followed.
5. Cleaning Unplug this unit from the wall
outlet before cleaning. Do not use liquid clean-
ers or aerosol cleaners. Use a damp cloth for
cleaning.
6. Do Not Use ttachments not recom-
mended by the manufacturer or they may
cause hazards.
7. Water and Moisture Do not use this
product near water for example, near a
bathtub, wash bowl, kitchen sink, laundry tub,
in a wet basement, or near a swimming pool
and the like.
8. ccessories Do not place this product on
an unstable cart, stand, tripod, bracket, or
table. The product may fall, causing serious
injury to a child or adult, and serious damage
to the appliance.
9. Ventilation This product should never be
placed near or over a radiator or heat register.
This product should not be placed in a built-in
installation such as a bookcase or rack unless
proper ventilation is provided or the manufac-
turer’s instructions have been adhered to. Any
slots or openings in the cabinet are provided
for ventilation. To ensure reliable operation of
the product and to protect it from overheating,
these openings must not be blocked or cov-
ered. The openings should never be blocked
by placing the product on a bed, sofa, rug, or
other similar surface.
10. Grounding or Polarization if this prod-
uct is equipped with a 3-wire line cord recep-
tacle, it is intended for use with a 3-wire prop-
erly grounded power socket. Do not defeat the
safety purpose of the supplied line cord and
plug.
11. Power Sources This product should be
operated only from the type of power source
indicated on the marketing label. If you are not
sure of the type of power supplied to your
home, consult your appliance dealer or local
power company.
12. Power-cord Protection Power-supply
cords should be routed so they are not likely
to be walked on or pinched by items placed
upon or against them. Pay particular attention
to cords at plugs, convenience receptacles,
and the point where they exit.
13. Lightning For added protection for this
product during a lightning storm, or when it is
left unattended and unused for long periods of
time, unplug it from the wall outlet.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT
EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE. DO NOT
OPEN THE CABINET WHILE OPERATING. REFER SERVICING TO
QUALIFIED PERSONNEL ONLY.
CAUTION: TO PREVENT ELECTRIC SHOCK, DO NOT USE THE THREE WIRE
CORD WITH AN EXTENSION CORD RECEPTIACLE OR OTHER
OUTLET UNLESS THE BLADES CAN BE FULLY INSERTED TO
PREVENT BLADE EXPOSURE.
An appliance and cart combination should
be moved with care. Quick stops, exces-
sive force and uneven surfaces may cause
the appliance and cart combination to
overturn.
The lightning flash with arrow head
symbol, within an equilateral triangle, is
intended to alert the user to the presence
of uninsulated “dangerous voltage” within
the product’s enclosure that may be of
sufficient magnitude to constitute a risk of
electric shock to persons.
The exclamation point within an equilateral
triangle is intended to alert the user to the
presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the appliance.
Service and Warranty 19
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Limited Warranty
Palstar Inc. warrants products
manu actured by it to be ree rom
de ects in material and workman-
ship under normal use and service
for a period of one ( ) year
from the date of delivery to
the first buyer (the “Warranty
Period”). Palstar Inc’s obligation
under this warranty is limited to
repair or replacement o the prod-
uct; at its option at the Palstar
actory in Piqua, OH.
E ective only when the product is
returned to the actory with all
transportation charges prepaid and
examination o the product dis-
closes in Palstar’s judgment, to
have been de ective during the
Warranty Period.
The Warranty Period shall not
extend beyond its original term
with respect to interim in-warranty
repairs by Palstar. This Warranty
Period shall not apply to any prod-
uct which has been repaired or
altered by anyone other than Pal-
star without prior written authori-
zation. Warranty does not extend
to any products which have been
subject to damage rom improper
installation, application or mainte-
nance in accordance with the oper-
ating speci ication. Palstar neither
assumes nor authorizes any person
to assume or it any obligation or
liability other than herein stated.
Repair Policy
When sending in a product or
service, please include a note
clearly describing the problem,
how you wish the item returned
and how you wish to pay or the
service.
Our service rate is $30 per hour
(1/2 hr. minimum).
Return Policy
All returns must receive prior au-
thorization rom Palstar. Returned
items must be received in origi-
nal—AS SHIPPED– condition in-
cluding the original box, manuals,
accessories, and copy o sales re-
ceipt. Returns must be within 14
days o purchase. Returned items
are subject to a 25% restocking
ee. Shipping is not re undable.
NOTE:
Keep the packing your
AT4K was shipped in
case a return for repair
is necessary.
Due to the high cost of
the custom foam inserts,
if you ship the tuner in
other than the original
packing, you will be
charged $ 5 for replace-
ment packing when we
return it to you.

18 Meter Board Adjustments
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Note: These adjustments control the calibration and accuracy of the
AT4K metering. Do not adjust unless you are sure the metering is
inaccurate, and you have accurate test equi ment to check against.
Reverse Reverse Forward Forward
Low High Low High
Peak Peak
Low High
Peak Peak Power On/Off
Hold Range
Note: The adjustment pots on your meter board may differ in
appearance from the photo raph.
1-800-773-7931 W WW.PALST AR . CO M
Important Safeguards cont’d) 3
14. Power Lines An outside antenna sys-
tem should not be located in the vicinity of
overhead power lines, other electric light or
power circuits, where it can fall into such
power lines or circuits. When installing an
outside antenna system, extreme care should
be taken to keep from touching such power
lines or circuits as contact with them may be
fatal.
15. Overloading Do not overload wall out-
lets and extension cords as this can result in a
risk of fire or electric shock.
16. Object and Liquid Entry Never push
objects of any kind into this product through
openings as they may touch dangerous volt-
age points or short-out parts that could result
in a fire or electric shock. Never spill liquid of
any kind on the product.
17. Servicing Do not attempt to service this
product yourself as opening or removing
covers may expose you to dangerous voltage
or other hazards. Refer all servicing to quali-
fied service personnel.
18. Damage Requiring Service Unplug this
product from the wall outlet and refer servicing
to qualified service personnel under the fol-
lowing conditions:
a. When the power-supply cord or plug is
damaged.
b. If liquid has been spilled, or objects have
fallen into the product.
c. If the product has been exposed to rain or
water.
d. If the product does not operate normally by
following the operating instructions. Adjust
only those controls that are covered by the
operating instructions. An improper adjust-
ment may result in damage and will often
require extensive work by a qualified
technician to restore the product to its normal
operation.
e. If the product has been dropped or the
cabinet has been damaged.
f. When the product exhibits a distinct change
in performance this indicates a need for
service.
19. Replacement Parts when replacement
parts are required, be sure the service techni-
cian has used replacement parts specified by
the manufacturer or have the same character-
istics as the original parts. Unauthorized sub-
stitutes may result in fire, electric shock or
other hazards.
20. Safety Checks Upon completion of any
service or repairs to this product, ask the
service technician to perform safety checks to
determine that the product is in proper operat-
ing condition.
21. Outdoor ntenna Grounding Before
attempting to install this product, be sure the
antenna or cable system is grounded so as to
provide some protection against voltage
surges and built-up static charges.
a. Use No.10 AWG copper, No.8AWG alumi-
num, No.17AWB copper-clad steel or bronze
wire or larger, as ground wire.
b. Secure antenna lead-in and ground wires to
house with stand-off insulators spaced from 4
feet to 6 feet apart.
c. Mount antenna discharge unit as close as
possible to where lead-in enters house.
d. A driven rod may be used as the grounding
electrode where other types of electrode
systems do not exist. Refer to the National
Electric Code, ANSI/NFPA 70-1990 for infor-
mation.
e. Use jumper wire not smaller than No.6
AWG copper or equivalent, when a separate
antenna grounding electrode is used.

4 Table of Contents
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Important safeguards 2
Table of Contents 4
General Description 5
Installation 6
Unpacking 6
Location 6
Installation Procedures 6
Rear Panel Connections 7
Front Panel Description 8
T4K Schematic 10
Operating Your T4K 12
Before Operating 12
Tuning 12
Pre-tune Settings 12
Power Specifications 16
Troubleshooting 16
Specifications 17
Meter Board djustments 18
Service and Warranty 19
Thank you for purchasing a Palstar AT4K Antenna Tuner. This
antenna tuner has been designed and manufactured to high qual-
ity standards, and will provide reliable operation for many years.
Please carefully read the Owner’s Manual in order to take advan-
tage of the many interesting features that will provide years of en-
joyable amateur
Specifications 17
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Front Panel Indicators and Controls
Metering Dual movement cross needle power and frequency
compensated coupler
Controls
Input Tuning 480 pF variable capacitor (6kV Peak)
Output Tuning 480 pF variable capacitor (6kV Peak)
Inductance 28 µH roller ceramic body roller inductor wound
with 10 gauge wire
Antenna Selector Switch 6 position:
Coax 1 tuned and tuner bypass
Coax 2 tuned and tuner bypass
Bypass and balanced antenna
Wafer switches are ceramic (7kV/10A)
Power Range Switch 2 position 300 Watts-LO /3000 Watts-HI
Rear Panel Connectors
Coax connectors SO239 connector (silver/gold/TFE)
Balanced Line Dual, High Voltage Nylon66TM terminal posts
Other
Frequency Coverage 1.8 29.5 MHz
Power 2500 W single tone continuous, 4 kW PEP
Impedance Range See chart of power/complex Z on page 16 for
per band ratings
Balanced Output 1:1 current type Balun at input-Ferrite
Dimensions 6.5”H x 15”W x 16”D (incl. terminals)
Weight 22 lbs.
Materials Chassis parts, brackets and top cover are gold
chem-film coated aluminum (.090” thick). Powder
coating on painted parts.

16 Operating Your AT4K
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Troubleshooting
If you hear a spitting sound while
tuning your AT4K at high power,
you are probably tuning into an imp-
edance that is on the low side (20Ω –
40Ω).
In this event, either reduce transmit-
ter/ampli ier power to a lower setting,
or change to a higher antenna im-
pedance by using a di erent antenna or
modi ying the existing antenna.
As seen in the chart to the right, an
antenna capacitance setting that is too
low under these conditions will result
in excessivly high voltages, high losses,
and poor e iciency.
In the irst instance the tuner will arc
and su er almost 16% loss, o which
80% will be dissipated in the roller
inductor.
1500 Watts into a 25 Ω load @3.5Mhz
8 Ω − 15 Ω 500 watts (all bands)
15Ω − 25Ω 1000 watts (all bands)
25Ω − 50Ω 1500 watts (all bands)
50Ω − 2000Ω 160M — 2000 watts
80M - 15M — 2500 watts
10M — 1000 watts (29.5 MHz
max)
Power Specifications (assuming single tone key down)
Antenna Impedance Max Power Rating
IF IN ANY DOUBT ABOUT YOUR ANTENNA
IMPEDANCE PLEASE MEASURE IT WITH A
PALSTAR ZM30 ANTENNA ANALYZER BEFORE
ATTEMPTING HIGH POWER OPERATION.
Ant Cap Inductor Voltage Loss
100 pF 11.7 µH 4550 16%
200 pF 6 µH 2400 8%
300 pF 4 µH 1600 6%
General Description 5
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The Palstar AT4K Antenna
Tuner is an American made im-
pedance matching network that
can provide unbalanced or bal-
anced output.
The AT4K T-matching network
utilizes a 1:1 unbalanced-to-
balanced transformer in the in-
put of the network. When the
network is properly tuned, a 50
Ohm impedance will be pre-
sented to both the input and
output of the balun allowing it to
operate at maximum efficiency.
The AT4K optimizes the per-
formance of your antenna and
transmitter by providing adjust-
able impedance matching using
a T type circuit configuration.
The AT4K also measures the
power and Voltage Standing
Wave Ratio (VSWR) which al-
lows you to tune the SWR to the
lowest ratio for the selected
transmit frequency.
Integrated into the AT4K is a
frequency compensated, lighted
dial, dual-movement SWR me-
ter. The meter features the abil-
ity to read True Active Peak and
Peak Hold.
Designed to handle both Bal-
anced line feeds and coax
feeds, the AT4K features a
front panel mounted switch to
select between feeds.
Tuning is achieved with the front
panel mounted controls. The
dual Vernier dials allow for tun-
ing with precision and accuracy,
while the Inductor crank handle
facilitates coarse adjustments.

W RNING: Balanced antennas will produce high
RF voltages at the output post connectors. RF
burns may result if touched during transmission.
6 Installation
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Un acking
Carefully remove the AT4K from
the shipping carton and inspect
it for signs of damage. If any
damage is apparent, notify the
transportation carrier or dealer
immediately. We recommend
keeping the packing carton
for moving, storing or reship-
ping the tuner to us for repair
if required.
Location
Select a location for the AT4K
that allows the connectors to be
free from any possible contact
with people, pets or objects dur-
ing operation and with unre-
stricted air flow for cooling.
Installation Procedures
Connect a coax cable from your
transmitter to the RF INPUT
connector on the rear panel.
Keep the cable as short as pos-
sible. If you use a linear ampli-
fier, connect your transmitter to
the linear amplifier input and the
linear amplifier output to the
AT4K. Connect coax cable from
your antenna to the COAX 1 or
COAX 2 connector on the rear
panel. These connectors are
either direct from the transmitter
or through the tuned circuit de-
pending on the setting of the
OUTPUT SELECTOR switch on
the front panel.
For coax feed (unbalanced)
select the CO X (OUT) switch
position. This done by switch-
ing the red TUNED OUTPUT
button on the lower front
panel between the Output
knob and the Inductor knob to
the CO X (OUT) position.
For a balanced feed antenna,
connect a balanced feedline to
the white BALANCED OUTPUT
posts on the back panel and
make sure that the red TUNED
OUTPUT button on the lower
front panel is in the BALANCED
(IN) position.
Connect a dummy load to the
BYPASS connector using a
coax cable. This lets you select
the dummy load from the OUT-
PUT SELECTOR switch. Any
antenna that does not require
the use of an antenna tuner may
be connected to the BYPASS
connector if desired.
Connect supplied 12VDC @
500ma wall adapter to rear
panel Power Jack. Power is
necessary for metering, relay
and meter lamp to work.
Operating Your AT4K 15
1-800-773-7931 W WW.PALST AR . CO M
- i you hear a spitting sound while tuning at high power you
are probably tuning into an impedance that is on the low
side (20Ω - 40Ω). (Please see page 16 or more detailed
instructions.)
4. Any time a new or di erent antenna is connected, it is
necessary to repeat the tuning procedure or the new an-
tenna. Be sure to write down the new settings or uture
use with that antenna
5. Once every 4-6 months clean the roller coil with 70%
isopropyl alcohol and a clean cotton cloth. Do not remove
the conducting grease on the rod that guides the roller
wheel. Do not transfer any of the conducting grease
from the rod to the roller coil body, as this will contami-
nate the windings .

14 Operating Your AT4K
1-800-773-7931 W WW.PALST AR . CO M
Operating Notes:
1. An SWR o 1:1 is best, but an SWR as high as 2:1 may be
acceptable. Check your transmitter/ampli ier manual or de-
tails.
2. I you cannot get an acceptable SWR, lengthen or shorten
your antenna and/or eedlines and retune.
VERY HIGH OR VERY LOW IMPEDANCE LOADS ARE TO
BE APPROACHED WITH EXTRA CAUTION, ESPECIALLY
WHEN YOU ARE GOING TO USE HIGH POWER. THE
USE OF AN RF ANALYZER E.G. A PALSTAR ZM-30 AN-
TENNA ANALYZER) WOULD BE ADVISABLE TO MEAS-
URE AND UNDERSTAND THE KIND OF LOAD YOU ARE
ATTEMPTING TO USE.
3. I you get low SWR readings at more than one setting,
use the setting that gives:
• highest FORWARD power reading
• lowest REFLECTED power reading
• uses the largest capacitance (highest number) on the
ANTENNA control
It is important to remember that consistent with low SWR
indicated on the tuner meter you must have, and adjust or:
- the largest capacitance (highest number) on the output
control to keep the losses low, and the voltage that would
appear on the antenna capacitor within the 5KV rating
Installation 7
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12 VDC INPUT (2.1 mm
plug) or supplied
12VDC @ 500mA wall
adapter to power the
metering unctions, me-
ter lamp, and relay.
RF INPUT coaxial
connector or input
rom transmitter or
ampli ier.
GROUND post/wing nut
ground connector.
BALANCED OUTPUT two
nylon High Voltage post
connectors or output to RF
balanced twin-lead antennas.
Relay switched.
COAX 2 coaxial connector or
output to Antenna Two.
COAX 1 coaxial connector or
output to Antenna One.
BYPASS coaxial connector
or output to dummy load
or third coax output. By-
passes tuner, but meter
circuits are on i 12VDC
is connected to rear panel
jack.
FIGURE 1 REAR PANEL CONNECTORS

8 Front Panel Description
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. POWER/SWR METER Dual needle meter displays FOR-
WARD and REFLECTED power in watts. SWR is measured
where the two needles intersect on the red scale.
2. DIRECT/TUNED MODE SWITCH Six-position rotary
switch selects an output coaxial connector with DIRECT mode
which bypasses the tuner, and TUNED mode which passes the
signal through the tuner components.
a. BYPASS Selects BYPASS COAX connector, bypassing the
tuner matching circuit but providing SWR, FORWARD & RE-
FLECTED power meter readings. Many operators connect a
dummy load to the Bypass connector so it can be selected by
switch.
b. DIRECT COAX Selects COAX 1 connector bypassing
the tuner matching circuit but providing SWR, FORWARD and
REFLECTED meter readings.
c. DIRECT COAX 2 Selects COAX 2 connector bypassing
the tuner matching circuit but providing SWR, FORWARD and
REFLECTED meter readings.
1 2 3 4 5 6
7
8 9 10
Operating Your AT4K 13
1-800-773-7931 W WW.PALST AR . CO M
4. Set POWER RANGE switch to 300 W (Power Range Me-
ter Switch button OUT).
5. Set OUPUT SELECTOR switch to the position matching
your antenna connection. To tune your antenna, the switch
selection must be set to: COAX 1 TUNED, COAX 2
TUNED or WIRE (BALANCED ANTENNA). Selecting
COAX 1 DIRECT, COAX 2 DIRECT or BYPASS bypasses
the tuning section. Also, the tuned output switch (#8 on pg.
8) must be set to the correct position: IN or balanced,
OUT or coax.
6. Key your transmitter and adjust the power level or a
reading o 100-150 watts on the FORWARD scale. Adjust
the INPUT, OUTPUT and INDUCTOR controls or a mini-
mum REFLECTED reading control.
7. Read the SWR on the red scale at the point where the
two needles intersect. Repeat TUNING the input and an-
tenna controls until the lowest SWR reading is obtained.
This procedure takes patience the first time. The input
and antenna controls vary the capacitors and provide
fine adjustments. The roller inductor crank control pro-
vides coarse adjustment.
8. When you have tuned your antenna to the best SWR,
record the settings o the INPUT, ANTENNA and INDUC-
TANCE controls on the chart above or uture re erence.
When you retune, use these settings as your starting point.
CAUTION: When approaching the end stops (readings
of 0 and 228 on the turns counter) of the roller inductor,
SLOW DOWN. Slamming the roller wheel into the
mechanical end stops on either end of the roller induc-
tor can damage it.

12 Operating Your AT4K
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CAUTION — Before Operating
1. To avoid possible damage to the AT4K set INPUT, OUT-
PUT, and INDUCTOR controls as outlined in the chart be-
ore applying transmitter power.
2. Begin tuning with your transmitter/amp into the tuner set
at a low output power setting (100-150 Watts).
Tuning
1. Select the band and requency o desired operation.
2. Set INPUT, OUTPUT, and INDUCTOR controls to the
suggested settings be ore applying transmitter power (see
chart below). Actual settings will vary rom antenna to an-
tenna.
3. Set your transmitter/ampli ier to a low power output
(100-150 watts). I your transmitter/ampli ier combination
has a LOW POWER position, select that position to obtain
the 100-150 watts or the initial tune-up.
WARNING: DO NOT OPERATE THE AT4K
WITH THE COVER OFF.
INPUT C P OUPUT C P INDUC TOR
B ND Sug-
gested
ctual Sug-
gested
ctual Sug-
gested
ctual
160 M 59 64 81
80 M 57 66 169
40 M 53 77 206
20 M 44 43 210
15 M 21 19 222
10M 21 12 229
d. TUNED COAX Selects COAX 1 connector through the
impedance matching T circuit.
e. TUNED COAX 2 Selects COAX 2 connector through the
tuner matching T circuit.
f. BALANCED OUT Selects the balanced output connectors
located a ter the impedance matching circuit.
3. PEAK HOLD Select (IN) to hold Peak readings or approxi-
mately 2 sec. on the SWR meter.
4. PEAK Select PEAK (IN) or AVGERAGE (OUT) power read-
ings.
5. RANGE Select metering range: 3000 Watts (IN) or 300
Watts (OUT).
6. POWER Select (IN) to turn on Peak/Hold metering with
backlight.
7. INDUCTOR 24 µH, continuously variable, steatite ceramic
core roller inductor driven by a crank handle. Maximum induc-
tance is a turns counter reading o zero, minimum inductance is
228.
8. TUNED OUTPUT BALANCED (IN) li ts ground o roller
inductor or balanced line eed. Direct/Tuned switch must be in
the TUNED BALANCED LINE position. COAX (OUT) puts di-
rect ground on roller inductor or coax eed. Direct/Tuned
switch must be set to TUNED Coax 1 or Coax 2.
9. OUTPUT Continuously adjustable output capacitor with
Vernier. Minimum capacitance is zero on dial and 100 is maximum
capacitance.
0. INPUT Continuously adjustable input capacitor with
Vernier. Zero is minimum capacitance and 100 is maximum ca-
pacitance.
Front Panel Description 9
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10 AT4K Schematic
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AT4K Schematic 11