AT2K 2000 Watt Antenna Tuner AT2K 2000 Watt Antenna

PALSTAR
Palstar products are designed by
Hams for Hams carrying on the
Palstar tradition for high-quality
products designed and
manufactured in Ohio, USA.
AT2K 2000 Watt Antenna Tuner
Technical Manual
AT2K 2000 Watt
Antenna Tuner
l 2000 W PEP SSB, 1500 W single tone
l 160 m to 10m
l Variable capacitor with vernier drive
l Dual movement cross needle meter
l 5” x 14.5” x 13.5”
9676 N. Looney Rd,
Piqua, OH 45356 USA
(937) 773-6255
(800) 773-7931
(937) 773-8003 (Fax)
www.palstar.com
PALSTAR
Designed and Manufactured in the USA
Copyright 2014 Palstar, Inc.
AT2K SPECIFICATIONS
l METERING:
AT2K GENERAL DESCRIPTION
Dual movement cross-needle power
and frequency compensated coupler
l INPUT & ANTENNA TUNING: Var iable capacitor 413pF 4.5 Kv
6:1 Ver nier Dr ive
l INDUCTANCE:
25 μH roller inductor; 12 ga. wire wound
on steatite ceramic core, silver plated
bar and wheel
l ANTENNA SELEC TOR SWITCH: 6 position:
Coax 1 - tuned and tuner bypass
Building on success, Palstar upgraded the best-selling AT1500CV
throughout to create the American-made Palstar AT2K Antenna Tuner.
The AT2K optimizes the performance of your antenna and transmitter
by providing adjustable impedance matching using a T-type circuit
configuration.
Coax 2 - tuned and tuner bypass
Switch wafers are 3 kV rated
l POWER R ANGE SWITCH: 2 position 300 W / 3000 W
l R E A R PA N E L C O N N E C T O R S :
The AT2K also measures the power (upgraded to include a PEAK/PEAK
HOLD function) and Voltage Standing Wave Ratio (VSWR or SWR),
which allows you to tune the SWR to the lowest possible for the
selected transmission frequency.
SO-239: RF Input, Coax 1 & 2, Bypass
COAX: Balanced line (optional balun)
END FED WIRE: H igh Voltage N ylon66™
terminal post & ground post
The AT2K also features a precision steatite ceramic core roller inductor
with a plated roller wheel and roller shaft. The smaller size permits
operation on 6 meters.
1 2 V D C I N P U T : 1 4 m m c o n n e c t o r, 2 . 1 m m I D ,
5.5mm OD, center positive, 200 ma
l FREQUENC Y COVER AGE: 1.8 - 54 MHZ
l POWER MAXIMUM:
A high voltage ceramic wafer switch allows selection between coax
feedlines or wire-fed antennas. DIRECT switch positions bypass the
impedance matching circuit but allow for the SWR, FORWARD, and
REFLECTED and PEAK power meter FUNCTIONS.
2000 W PEP SSB, 1500 W single tone
l IMPEDANCE RANGE: 20 to 1500 Ω, 160m to 10m
(assuming resisitive load)
Reduce power for lower Z-range
l BA L A N C E D O U P U T:
4:1 current type balun (optional external)
l DIMINSIONS:
5” H x 14.5“ W x 13.5” D
l W E I G H T:
13 LBS, 6 Kg
l CHASSIS & COVER:
1 1 g a . , . 0 9 0 g o l d I r i d i t e Tr e a t e d A l u m i n i u m
Tuning is achieved with the front panel mounted controls. The 6:1 ratio
Vernier dials allow for tuning with precision and accuracy, while the
Inductor crank handle facilitates coarse adjustments. The range of the
meter (300W/3000W) is selcted by a push button switch located on the
front panel.
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PALSTAR
REAR PANEL
INSTALLATION
U N PA C K I N G
C a r e f u l l y r e m o v e t h e AT 2 K f r o m t h e s h i p p i n g c a r t o n a n d
inspect it for signs of damage. If any damage is apparent,
n o t i f y t h e t r a n s p o r t a t i o n c a r r i e r o r d e a l e r i m m e d i a te l y.
K E E P T H E PA C K I N G C A R T O N f o r m o v i n g , s t o r i n g , o r
reshipping the tuner to us for repair if required.
COAX 1 coaxial connector
for output to Antenna 1
L O C AT I O N
S e l e c t a l o c a t i o n f o r t h e AT 2 K t h a t a l l o w s t h e c o n n e c t o r s
to be free from any possible contact with people, pets,
or objects during operation and with unrestricted air
fl o w f o r c o o l i n g .
COAX 2 coaxial connector
for output to Antenna 2
2.1 mm
FEMALE plug
Grey
TRACE ID
Protection
Reverse diode
RF INPUT
coaxial connector
for input from transmitter
or amplifier
Red Heat Shrink
cover
+ To 12-13.8v
- Power Supply
GROUND post/wing nut
AT 2 K D C P O W E R C O R D
ground connector
COAX-BAL-WIRE
I N S TA L L AT I O N P R O C E D U R E
Connect a coax cable from your transmitter to the RF
INPUT connector on the rear panel. Keep the cable as
s h o r t a s p o s s i b l e . I f y o u u s e a l i n e a r a m p l i fi e r, c o n n e c t
y o u r t r a n s m i t t e r t o t h e l i n e a r a m p l i fi e r i n p u t a n d t h e
l i n e a r a m p l i fi e r o u t p u t t o t h e AT 2 K .
Use this connector
to connect an optional
external 1:1 or 4:1 balun
for balanced or wire feed
antennas
12 VDC INPUT
(2.1 mm plug,
center pin +)
12 VDC adapter
200 mA to power
the meter lamp
BYPASS coaxial
D O N O T U S E M O R E T H A N 1 5 0 0 WAT T S ( s i n g l e t o n e )
t h r o u g h t h e t u n e r.
Page 3
connector for output
to dummy load or third
coax output. Bypasses
tuner, but meter circuits
are on if AC adapter is
connected to rear panel
PALSTAR
FRONT PANEL DESCRIPTION
1
6
2 3 4 5
7
8
a. DIRECT BYPASS selects BYPASS COAX CONNECTOR bypassing the
impedance matching circuit, but providing SWR, FORWARD, and
REFLECTED power meter readings.
9
b. DIRECT COAX 1 selects COAX 1 CONNECTOR bypassing the tuner
matching circuit, but providing SWR, FORWARD, and REFLECTED meter
readings.
1. POWER/SWR METER Dual needle meter displays FORWARD and
REFLECTED power in watts. SWR is measured where the two needles
intersect on the red scale. SWR is printed on meter face.
c. DIRECT COAX 2 selects COAX 2 CONNECTOR bypassing the tuner
matching circuit, but providing SWR, FORWARD, and REFLECTED meter
readings.
2. PEAK HOLD Select to read Peak Hold on the SWR meter. Peak switch [3]
must be in PEAK position.
3. PEAK Selects between PEAK and AVERAGE power metering display.
d. TUNED COAX 1 selects COAX 1 CONNECTOR through the impedance
matching T circuit.
4. RANGE Two-position switch selects the range of FORWARD and
REFLECTED power displayed on the power meter. When the RANGE
button is OUT, the FORWARD meter scale reads 300 watts full scale and
the REFLECTED meter scale reads 60 watts full scale. When the RANGE
button is IN, the FORWARD meter scale reads 3000 watts full scale and
the REFLECTED meter scale reads 600 watts full scale.
e. TUNED COAX 2 selects COAX 2 CONNECTOR through the impedance
matching T circuit.
7. INPUT Continuosly adjustable input capacitor.
8. OUTPUT Continuously adjustable output capacitor.
5. ON Select to turn on the backlight in the meter and enable metering,
and 160 meter functions. The jack on the back panel must be supplied
with 12 VDC for these functions to work.
9. INDUCTOR 25μH continuously variable ceramic roller inductor driven
by a crank handle. Coupled to the crank handle is a gear-driven
precision mechanical counter. The end stop readings
on the turns counter are ZERO and 279. Zero is maximum inductance and 279 is minimum inductance.
6. DIRECT-TUNED MODE SWITCH Six-position rotary switch selects an
output connector as follows:
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PALSTAR
PALSTAR
AT2K SCHEMATIC
413
413
25
Page 5
© COPYRIGHT PALSTAR 2011-2014
METER BOARD ADJUSTMENTS
Reverse
Low
Peak
Hold
Reverse
High
Forward
Low
INSIDE VIEW
COUPLER
VARIABLE
CAPACITORS
METERING
ASSEMBLY
PEAK/HOLD
PCB
Forward
High
Peak Peak Power Peak On/Off
Low Range High
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ROLLER
INDUCTOR
PALSTAR
OPERATING YOUR AT2K
D O N O T E X C E E D 1 0 0 0 W AT T S A V E R A G E ( S I N G L E T O N E )
B E F O R E O P E R AT I N G
1 . To a v o i d p o s s i b l e d a m a g e t o t h e AT 2 K s e t I N P U T, O U T P U T,
5. Set RANGE switch to 300 W (button out).
INDUC TOR, and POWER RANGE switches as outlined in the
6. Set the DIRECT/TUNED mode switch to the TUNED
c h a r t b e l o w b e f o r e a p p l y i n g t r a n s m i t t e r p o w e r.
p o s i t i o n m a t c h i n g y o u r a n t e n n a c o n n e c t i o n . To t u n e y o u r
2. Begin tuning with your transmitter/amp feeding the tuner
antenna, the switch selec tion must be set to: COAX 1 TUNED,
set at a low output power setting (50-100 Watts max).
C O A X 2 T U N E D , o r B A L A N C E D L I N E . S e l e c t i n g C O A X 1 D I R E C T,
C O A X 2 D I R E C T, o r B Y PA S S b y p a s s e s t h e t u n i n g c i r c u i t r y a n d
WA R N I N G : D O N O T O P E R AT E T H E
AT 2 K W I T H T H E C O V E R O F F.
tuning is not possible.
TUNING
7 . R o t a t e t h e I N P U T, A N T E N N A , a n d I N D U C T O R c o n t r o l s f o r
1. Select the band and frequency of desired operation.
m a x i m u m n o i s e o r s i g n a l a s h e a r d o n y o u r r e c e i v e r. R e f e r t o
2. Set TUNE and INDUC TOR controls to the suggested setting
preset tuning chart on page 9.
before applying transmitter power (see chart). Actual settings
8. Key your transmitter and adjust the power level for a
will vary from antenna to antenna.
r e a d i n g o f 5 0 - 1 0 0 w a t t s o n t h e F O R WA R D s c a l e . A d j u s t t h e
3 . S e t y o u r t r a n s m i t t e r / a m p l i fi e r t o a l o w p o w e r o u t p u t . I f y o u r
I N P U T, O U P U T, a n d I N D U C T O R c o n t r o l s f o r a m i n i m u m
transmitter has a TUNE position, select that position.
R E F L E C T E D r e a d i n g w h i l e m a i n t a i n i n g a F O R WA R D r e a d i n g
4 . I f y o u u s e a l i n e a r a m p l i fi e r, s e t i t t o S TA N D B Y. D o n o t u s e
of 50-100 watts using your transmitter power control.
t h e l i n e a r a m p l i fi e r u n t i l t h e AT 2 K i s t u n e d .
9. Read the SWR on the red scale at the point where the two
BAND
INPUT
SUGGESTED
ACTUAL
OUTPUT
SUGGESTED
ACTUAL
needles intersect. Repeat TUNING the input and antenna
INDUCTOR
SUGGESTED
controls until the lowest SWR reading is obtained. The SWR
ACTUAL
s h o u l d b e 2 : 1 o r l o w e r.
160 M
50
65
32
80 M
55
45
183
r e c o r d t h e s e t t i n g s o f t h e I N P U T, A N T E N N A , a n d I N D U C TA N C E
40 M
45
56
239
controls on the chart above for future reference. When you
20 M
50
60
264
retune, use these settings as your starting point.
17 M
50
60
267
15 M
24
35
268
12 M
24
35
271
10 M
26
40
274
6M
40
30
265
10. When you have tuned your antenna to the best SWR,
T h i s p r o c e d u r e t a k e s p a t i e n c e t h e fi r s t t i m e . T h e i n p u t
and antenna controls vary the capacitors and provide
fi n e a d j u s t m e n t s , w h i l e t h e r o l l e r i n d u c t o r c r a n k
provides coarse adjustment.
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PALSTAR
RESTORING THE INDUCTOR WHEEL
NOTES:
1. A SWR of 1:1 is best, but an SWR as high as 2:1 may be
a c c e p t a b l e . C h e c k y o u r t r a n s m i t t e r / a m p l i fi e r m a n u a l f o r
details.
2. If you cannot get an acceptable SWR, lengthen or
shorten your antenna and/or feedlines and retune.
When approaching the end stops of the roller inductor
( re a d i n g s o f Ze ro o r 2 7 9 ) S LO W D O W N . S l a m m i n g t h e
roller wheel into the mechanical end stops on either
end of the roller inductor will decrease the pressure of
the wheel against the wire wound on the ceramic form.
3. If you get low SWR readings at more than one setting,
use the setting that gives:
- h i g h e s t F O R WA R D p o w e r r e a d i n g
- lowest REFLECTED power reading
To RESTORE wheel pressure on
the inductor push down on the
flat springs soldered to the
wheel shaft located on each
end of the shaft.
- uses the largest capacitance (highest number) on the
INPUT and ANTENNA controls.
4 . A n y t i m e a n e w o r d i ff e r e n t a n t e n n a i s c o n n e c t e d , i t i s
necessary to repeat the turning procedure for each
antenna.
5. Once every 4-6 months clean the roller coil with Deoxit
D5 contact cleaner 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
b o d y,
as
this
will
contaminate the windings.
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PALSTAR