Alpha Power ALPHA 6 User manual

INTERIM MANUAL Page i
ii
i
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
A
AA
ALPHA
LPHALPHA
LPHA 6
66
6
O
OO
OPERATING
PERATINGPERATING
PERATING M
MM
MANUAL
ANUALANUAL
ANUAL
PRELIMINARY DRAFT
PRELIMINARY DRAFTPRELIMINARY DRAFT
PRELIMINARY DRAFT
ALPHA/POWER
by CrossLink, Inc. RF
Power for Communications and Industry
6185 Arapahoe Road,
Boulder, Colorado 80303-1401
[phone] * FAX [phone]

ALPHA POWER PRODUCTS
ALPHA 6
Operating Manual
DISCLAIMER
Information in this document is subject to change
without notice. Information provided by CrossLink
Inc.® is believed to be correct and reliable. However,
no responsibility is assumed by CrossLink Inc., unless
otherwise expressly taken. Companies, names, and
data used as examples are fictitious, unless otherwise
noted.
No part of this document may be reproduced or
transmitted in any form or by any means, graphic,
electronic, or mechanical, for any purpose without the
express permission of CrossLink, Inc. CrossLink, Inc.
may have patents or pending patents, trademarks,
copyrights, or other property rights covering the
subject matter in this document. The furnishings of
this document does not give you license to these
patents, trademarks, copyrights, or other intellectual
property, except as expressly written in any license
agreement form
CrossLink Inc.
6185 Arapahoe Road • Boulder, CO 80303
Phone [phone] • Fax [phone]
Read this entire manual and all other publications
pertaining to the work to be performed before you
install, operate, or maintain this equipment. Practice
all product safety instructions and precautions.
CrossLink, Inc. provides information on its products
and associated hazards, but it assumes no
responsibility for the after-sale operation of the
equipment or the safety practices of the Owner or
User. See Warranty and Notices Appendix.
©Copyright 2001 by CrossLink Inc.
All rights reserved.

Page
PagePage
Page 2
22
2
Revision 1.0
Revision 1.0Revision 1.0
Revision 1.0
Table of Contents
OWNER ASSISTANCE.................................................................................................................................4
EQUIPMENT SHIPPED.................................................................................................................................4
SAFETY: INSTALLATION AND OPERATION ...............................................................................................5
BEFORE INSTALLING YOUR ALPHA 6........................................................................................................6
AC POWER SOURCE..................................................................................................................................7
ANTENNA..................................................................................................................................................7
COAX AND CONNECTORS..........................................................................................................................8
AIR FLOW.................................................................................................................................................. 8
RF SAF ETY................................................................................................................................................8
TRANSFORMER INSTALLATION (SEE FIGURES 2-4) ................................................................................... 9
INSPECTION OF TUBE & CHIMN EY ............................................................................................................9
AC PRIMARY CONNECTIONS & AMPLIFIER GRO UNDING .......................................................................10
POWER CORD CONNECTIONS — WARNING!..................................................................................... 10
RF GROUNDING ......................................................................................................................................11
COAXIAL CABLE TYPES & CONNECTORS ............................................................................................... 13
T/R CONTROL CABLE .............................................................................................................................13
FIGURE 5: ALPHA 6 REAR PAN EL ........................................................................................................ 14
4.1 Control Functions.........................................................................................................................15
4.2 Tune-up.........................................................................................................................................15
Grid Current .......................................................................................................................................16
ALC .....................................................................................................................................................16
Tune-up Procedure.............................................................................................................................16
4.3 Reflected Power Protection ...................................................................................................17
4.4 Automatic Level Control (ALC) .............................................................................................18
FIGURE 6 – INSIDE TOP VIEW ................................................................................................................. 19
FIGURE 7 – FRONT PAN EL LOWERED...................................................................................................... 20
FIGURE 8 - INSIDE FRONT PANEL...........................................................................................................21
OPERATING AND MAINTENANCE NOTES...................................................................................22
TUBES.................................................................................................................................................22
INTERLOCKS.....................................................................................................................................22
FUSES.................................................................................................................................................23
PLATE OVERCURRENT RELAY.......................................................................................................23
FIGURE 9 - REAR PANEL CONNECTIONS .................................................................................................25
TROUBLESHOOTING HINTS ............................................................................................................26
DESIGN AND CIRCUIT OVERVIEW................................................................................................28
RF Amplifier Section (See Figure 6, 13).............................................................................................28
Power Supplies (Figures 6, 9, 12)......................................................................................................28
SAFETY.................................................................................................................................................29
ALPHA PRODUCTS WARRANTY.....................................................................................................30

INTERIM MANUAL Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Introduction
IMPORTANT
Critical precaution during installation of your Alpha 6:
While the cover is removed to install the power transformer, make sure that the tube
is properly installed as described below. Failure to do this may cause severe
damage or destruction of the tube. Such damage is not covered under warranty.
General Description of the ALPHA 6 Amplifier
The ALPHA 6 is a self-contained 6m VHF Linear power amplifier capable of continuous
operation at 1500 watts peak power output on SSB, keyed CW, SSTV, RTTY, digital
modes or FM, with no time limit. If periods of “continuous-key-down” carrier operation
will exceed 5 minutes, or if the amplifier is to be operated from 50 Hz mains, the optional
auxiliary cooling fan available from CrossLink must be installed to avoid possible damage
not covered by the warranty.
All shipped, units delivered within the USA and its territories are manually tunable to cover
the entire 6m amateur band from 50-54 MHz.
Specifications, ALPHA 6
Frequency Coverage: Amateur band 50-54 MHz.
Power Output: 1500 watts peak all modes, including SSB, CW and continuous or
modulated carrier. Carrier operation (e.g., A0, RTTY or FM) for more than 5 minutes at or
near maximum rated power requires use of the auxiliary cooling fan accessory.
Drive Power: 50 to 60 watts nominal for rated output.
Power Gain: Nominally 14 dB, a power increase of 25 times.
Input Impedance: 50 ohms nominal, unbalanced; VSWR <2:1.This manual provides all
information necessary to install and operate the ALPHA 6. Schematic diagrams are
available on request, at no charge to owners.
Section
1

INTERIM MANUAL Page 4
44
4
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Output Impedance: 50 ohms unbalanced.
MaximumLoad VSWR: 2:1 at full rated power output.
VSWR Trip: Automatic standby when reflected power >250
watts.
Intermodulation Distortion: 30 dB below rated output.
Harmonic Output: <-60 dBc.
Tubes: One Svetlana 4CX1600B ceramic-metal tetrode.
Cooling: Full-cabinet, ducted forced air using cushion-
mounted centrifugal blower.
Automatic Level Control (ALC): Negative from 0, adjustable.
Primary Power: 190-250 or 90-130 VAC nominal, 50-60 Hz,
fused at 20 amperes.
Power Transformer: 3+ kVA with strip-wound Hipersil core.
Protective Functions: Grid and screen current limiting; trip to standby
(automatic reset) for excessive VSWR or
average plate current, RF arc, severe mistuning;
AC off trip for HV fault; primary and step-start
fuses; cover AC interlock and HV crowbar
switches; AC inrush-current limiting (Step-
start).
Status Indicators: STANDBY, WAIT (initial turn-on time delay),
OPERATE and FAULT LEDs.
Metering: Dedicated, full-time LED bargraphs display
forward and reflected rf power; grid current
LEDs; LED bargraph selectable among plate
voltage, plate current, and tune-up functions.
Size: 7.5” H x 17” W x 16.5” D (19x43x39cm)
excluding controls, feet, and connectors.
Weight: 66lb. (30kg) net, 75lb (34kg) ship; two cartons.
Note: CrossLink reserves the right to change design and/or specifications without prior
notice or obligation.
Owner Assistance
Assistance is available from CrossLink Alpha Technical Support at 303.473.9232 x.141,
by fax at 303.473.9660, or by email at [e-mail].
Equipment Shipped
The Alpha 6 ships in two heavy-duty cardboard cartons. One carton holds the power
transformer and weighs 43 pounds; the second carton contains the amplifier and weighs 42
pounds.

INTERIM MANUAL Page 5
55
5
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Safety: Installation and Operation
The Alpha 6 is designed to meet international safety standards and FCC regulations.
However, one should always remember that the equipment works with high voltages that
are LETHAL!
This operating manual holds information, cautions and warnings that must be followed to
ensure safe installation and operation. Read Section 1 before attempting to unpack or
operate the amplifier. Failure to perform procedures properly may result in amplifier
damage, fire hazard, or electric shock.
Warnings:
!Never open the amplifier case without unplugging the unit from the wall outlet.
!Never stick objects into holes in the case.
!Never touch an antenna during transmission.
CAUTION
CAUTIONCAUTION
CAUTION –
––
– READ THE MANUAL CAREFULLY BEFORE INSTALLING
YOUR 6.
The ALPHA 6 is extremely easy to install and operate, but failure to carry out each
procedure exactly as described in the manual is likely to lead to amplifier damage
which is not covered under warranty. Damage to other station equipment may also
result.

INTERIM MANUAL Page 6
66
6
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Before Installing Your Alpha 6
1. Be careful not to twist or warp the
chassis when handling the amplifier
with its cover removed. Never lift
the chassis by a corner, especially
when the transformer is in place.
Never apply A-C power without the
transformer properly and fully
installed.
2. When installing or removing the
transformer, move carefully and
follow the instructions in this manual
exactly. Insure that all connectors
are properly mated and fully seated.
Don’t force them! Tuck the lifting
handle out of the way so the
interlock can close.
3. Insure that the tube is solidly seated
in its socket with the red silicone
rubber chimney firmly seated against
the chassis.
4. Connect the green conductor in the
Alpha 6 power cord only to the
power source neutral or ground.
Connecting the green wire to a
“hot” line is almost certain to cause
immediate damage. Triple check
your wiring before plugging in!
5. Make sure the primary power tap is
connected to the tap closest to your
actual AC voltage. See manual
section 4.
6. Solidly bond all station equipment
chassis together. Heavy braid, such
as the outer conductor of RG-8/U
coaxial cable, is recommended for
the purpose. This is important for
personal and equipment safety as
well as to avoid RF feedback.
7. Neverinstallcoverscrews longer
than ¼”. Longer screws may
penetrate internal boards or wiring
and cause severe damage. Make
sure each screw hole in the cover is
aligned with its corresponding
captive nut in the chassis before
inserting screws.

INTERIM MANUAL Page 7
77
7
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Station Engineering
Considerations
The 6 is capable of dramatically improving the performance of your amateur station. It is
important that you observe good engineering practices to achieve all the benefits of such a
station in a safe and reliable manner. This section gives a few hints for important things to look
for, but it is recommended that the user also consult a good source of general information such
as “The Radio Amateur’s Handbook” by the ARRL, especially if this is the first high-power
amplifier you have used.
AC Power Source
If you do not have a 220V ac outlet in your shack, you will need to get a licensed electrical
contractor to install one. A minimum of a 20 amp capacity is required. Select a location for
the outlet as close as possible to where you expect to operate the 6. If you are not sure, or
contemplate moving the amplifier, it may be cheaper to get a second outlet installed at the
same time. Ask your contractor for two or three matching plugs while he is there, as there
are several styles of connector available. Ask the contractor to measure the voltage and
record it, so you can set the line voltage tap on the Alpha 6 appropriately. If he can, ask him
to tell you the line voltage with a 10 Amp current draw, and use this value for setting the
transformer tap.
Antenna
Many antennas which are suitable for general use are unsuited for operation with a full 1500
watts of power. At this power level in a 50 Ohm circuit, the RMS current is 5.5 Amps and
the peak RF voltage is 387 Volts. With a 2:1 SWR, these values double: 11 Amps and 775
Volts. The voltage and current at various points in or on your antenna can actually be many
times these values.
On a simple dipole with sharp wire ends, corona (localized ionization) can easily occur.
Corona can (and has!) lead to fire in nearby objects. Traps in beams and verticals can heat
up significantly during high power operation. Instances of melting or flashover of traps have
occurred in many installations where insufficient thought has been given to their ratings.
If an antenna has been up for a long period of time, it may be worth taking it down for
inspection prior to full power operation. If any insulators are cracked or show signs of

InterimManual Page 8
88
8
Revision X
Revision XRevision X
Revision X
“tracking”, replace them. Doubling-up on insulators is also easy to do, and may save
problems. If there is any chance of people or objects coming close to the antenna, take steps
to move it higher, or place barriers so that this cannot happen.
Check the SWR of your antenna. If you have a favorite part of any band you use most often,
consider adjusting the antenna for minimum SWR in this part of the band.
Coaxand Connectors
The importance of a well constructed feedline system cannot be overstated. After all, the
purpose of the amplifier is to provide (coax and connectors continued) approximately 2 S
units (12+ dB) of improvement in your radiated signal. All too often installations are
encountered where cheap/poor/under-rated/old coax and connectors are probably
responsible for one S unit of degradation. This means you could have bought a 375 Watt
amplifier and achieved the same radiated signal by buying good quality feedline
components! Use the lowest loss 50 Ohm coaxial cable you can get your hands on. Use
new, clean connectors installed per the manufacturers recommendations. Clean the
connectors after soldering them, and before mating them with the amplifier. Make sure any
excess solder is removed from the connector, likewise any fragments of braid etc. Never use
old coax, which may have had moisture penetrate under the jacket. Run the coax in straight
lines as much as possible. Support it frequently using non-compressive clips so it does not
hang and stretch under its own weight. Avoid sharp bends (most manufacturers will specify
a minimum bend radius for their product). Make sure the transition from feedline to antenna
is waterproof. Provide for disconnection of the feedline when not in use.
Air Flow
It is critical that the 6 air flow is unrestricted in any way. Keep the top of the amplifier clear
of any restrictions. If you are mounting the amplifier in a console, make sure that the
exhaust air is properly and fully removed from the console. Poorly designed consoles can
result in outlet air being drawn back into the amplifier air intake and recirculated, getting
hotter and hotter, resulting in degraded amplifier performance or even failure. If you are
designing your own console, consider putting in additional fans and/or ducting to deal with
waste heat. Try to minimize the possibility of dust or other contamination getting drawn into
or falling on the amplifier.
RF Safety
The FCC requires users to check their installations for compliance with published values for
allowable exposure to RF fields. This information is available in ARRL publications, FCC
Printed rules, and on the web. CrossLink strongly recommends that this be done for any
installation, both fixed and at an expedition or contest site.
If you have any questions regarding engineering your 6 into your amateur radio station, do
not hesitate to call CrossLink Alpha Technical Support.

Page
PagePage
Page 9
99
9
Alpha 6 User Manual Rev X
Alpha 6 User Manual Rev XAlpha 6 User Manual Rev X
Alpha 6 User Manual Rev X
Interim Manual
Interim ManualInterim Manual
Interim Manual
PREPARING THE ALPHA 6 FOR
OPERATION
Transformer Installation (See Figures 2-4)
Remove the amplifier top cover to install the transformer. Only one possible transformer
orientation allows mating all its connectors without straining leads. Lift the transformer high
enough to clear the right side chassis lip and move it sideways into the chassis. USE
CAUTION--PROCEED SLOWLY to avoid damaging wires or components. From
underneath, insert the supplied bolts with washers through the clearance holes in the chassis
and into the nuts in the transformer base. CAUTION! Mate transformer connectors
carefully and gently to insure that all connector pins engage correctly and fully.
Inspection of Tube & Chimney
While the top cover is removed, make sure tube is firmly seated in its socket, rubber exhaust
chimney is fully and correctly installed, and anode connector is tightly clamped to tube.
The silicone rubber chimney installed on the 4CX1600B tube is an absolutely essential part
of the cooling system. Make sure the chimney is straight and fully installed so that the
bottom of the chimney is firmly against the tube deck and completely covers the airflow
openings in the deck. Tube cooling air must exit only through the tube anode fins; it must
not be allowed to escape outside them. Failure to ensure proper cooling airflow may result
in tube damage or destruction which is not covered under warranty.
Section
2