Alpha Radio 87A User manual

ALPHA RADIO PRODUCTS
ALPHA 87A
Operating Manual
DISCLAIMER
Information in this document is subject to change without
notice. Information provided by Alpha Radio Products Inc.®
is believed to be correct and reliable. However, no
responsibility is assumed by Alpha Radio Products, LLC.,
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 Alpha Radio Products, Inc. Alpha Radio Products, 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
Alpha Radio Products
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. Alpha Radio Products, LLC.
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 2005 by Alpha Radio Products, LLC.
All rights reserved.
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Alpha 87A User Manual Rev 2.0

Table of Contents
Introduction 3
Owner Assistance 3
Equipment Shipped 3
Safety: Installation and Operation 3
Before Installing Your Alpha 87A 4
Before Operating Your Alpha 87A 7
Overview of Amplifier Capabilities 9
ALPHA 87A Specifications 11
Figures 1-3 Transformer Installation 12
Unpacking and Preparing for Operation 13
Figure 4 – Inside Top View 15
Figure 5 – Front Panel Lowered 16
Figure 6 - Inside Front Panel 17
Control and Indicator Functions 19
Installation 21
ALPHAMAXTM Firmware 23
AlphaMax Operating Procedures 23
ALPHAREMOTETM Software 25
SAFETY 26
AlphaRemote Operating Procedures 27
Installing the AlphaRemote Software 28
How to Operate the 87A 31
Step-by-step Procedure 31
Pre-Tuning Procedure 32
Protective Functions and “Faults” 35
Soft Faults 35
Hard Faults 36
Fault Codes 37
RS-232 Serial Communications Link 41
Communications Link Set-up 42
Serial control lines 42
Remote Commands 44
Troubleshooting Suggestions 47
Owner Assistance 47
Overdrive related faults 47
ALC 47
Repeated power-off shutdowns 48
ALPHA 87A Functional Configuration 51
Principal Functional Components 51
Schematic Description 52
Schematics Available 52
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Alpha 87A User Manual Rev 2.0

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Alpha 87A User Manual Rev 2.0
Section
1
Introduction
The Alpha 87A is a self-contained HF linear amplifier. It provides continuous maximum-legal-power
on all amateur HF bands with self-tune capability.
This manual provides all information necessary to install and operate the ALPHA 87A. Schematic
diagrams are available on request, at no charge to owners.
Owner Assistance
Assistance is available from Alpha Radio Products at 303.473.9232 x.141, by fax at 303.473.9660,
or by email at [e-mail].
Equipment Shipped
The Alpha 87A 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.
Safety: Installation and Operation
The Alpha 87A 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 – READ THE MANUAL CAREFULLY BEFORE INSTALLING
YOUR 87A.
The ALPHA 87A 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.
Before Installing Your Alpha 87A
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 AC 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 both tubes are solidly seated
in their sockets with the red silicone
rubber chimneys firmly seated against
the chassis.
4. Connect the green conductor in the
Alpha 87A 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 checks 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. Never install cover screws 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.
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Alpha 87A User Manual Rev 2.0

Station Engineering Considerations
The 87A 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 87A. 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 87A
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 that 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 “tracking”, replace them.
Doubling-up on insulators is also easy to do,
and may save problems. If there is any
chance of people or object 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.
Coax and Connectors The importance of a
well-constructed feed line 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 375watt amplifier and achieved
the same radiated signal by buying good
quality feed line components! Use the lowest
loss 50 ohm coaxial cable you can get your
hands on. Use new, clean connectors Clean
the connectors after soldering them, and
before mating them with the amplifier. Make
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Alpha 87A User Manual Rev 2.0

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 feed line to antenna is waterproof.
Provide for disconnection of the feed line when not
in use.
Air Flow It is critical that the 87A airflow 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. Alpha Radio
Products 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 87A into your amateur radio station, do not
hesitate to call Alpha Technical Support. Installed
per the manufacturers recommendations.
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Alpha 87A User Manual Rev 2.0

CAUTION – READ THE MANUAL CAREFULLY BEFORE OPERATING
YOUR 87A.
The ALPHA 87A 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 also may result.
Before Operating Your Alpha 87A
1. You must set transceiver power output properly.
The Alpha 87A requires about 50 watts drive for
full rated output. Damage caused by
overdriving the ALPHA 87A will not be
covered under warranty. Fortunately, most
modern transceivers maintain quite consistent
output from band to band and mode-to-mode if
set up properly. We recommend that you only
run the Alpha 87A in high voltage mode, running
your amp in low voltage mode with high plate
current can damage components.
Setting the transceiver POWER or RF PWR
control IS NOT SUFFICIENT. Several popular
transceivers can generate RF spikes of 200-
300W or more unless the transceiver internal
ALC (drive level) is also adjusted carefully
according to its manufacturer’s instructions. This
typically is done with a knob labeled DRIVE (IC-
781, FT-1000), PROCESSOR OUT (TS-940, TS-
950) or, on SSB when speech processing is not
in use, MIC or MIKE.
2. The ALPHA 87A “faults” into STBY or OFF
when unsafe operating conditions occur. If
this happens, record which SEGMENT LEDs are
flashing to indicate a BCD fault number, and refer
to manual section 8.0.
3. On any frequency where your antenna
VSWR exceeds 1.5:1, it’s important to
manually program the ALPHA 87A for a
proper match. See manual sections 7.2-
7.4. Efficiency, linearity, and output often
can be improved even when VSWR is
less than 1.5:1. The 87A does not
contain an antenna tuner. The SWR will
need to be tuned via the antenna or an
external tuner connected to the output of
the Alpha 87A.
TO SAVE THE DATA TO MEMORY
after manually tuning your ALPHA 87A in
any given segment, first press ENTER;
then, while the ENTER LED is flashing,
press the desired SEGMENT button.
4. To operate the ALPHA 87A efficiently
and cleanly at power output much
different from 1.5kW it must be manually
tuned and loaded (i.e. programmed)
accordingly or AlphaMax must be turned
on. See Section 7.
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Alpha 87A User Manual Rev 2.0

5. Induced energy from nearby electrical
storms or other power transients may
damage components. Such damage is not
covered under warranty. It is important to
use a good lightning arrestor, and it is good
practice to disconnect and ground antenna
feed lines, and to disconnect A-C power,
when the equipment is not in use.
6. Never use an automatic antenna tuner into or
through the Alpha 87A. This will cause
damage to the input wattmeter & input relay.
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Alpha 87A User Manual Rev 2.0

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Alpha 87A User Manual Rev 2.0
Section
2
Overview of Amplifier
Capabilities
It is extremely important to thoroughly review the Installation and Operation sections of this manual
before attempting to use the ALPHA 87A. Failure to do so could result in serious damage not covered
under warranty.
 Continuous RF Output. The Alpha 87A
is capable of 1.5kW continuous RF
output on all commonly used modes and
on any authorized amateur frequency
from 1.8 to 29.7 MHz. Band change
and tune-up are microprocessor
controlled and no special cables or
adapters are required.
 Compatibility with popular amateur
transceiver and exciters. The Alpha 87A
requires approximately 50-55 watts peak
RF drive for 1.5kW output. No user
programming or adjustments are
necessary for maximum-legal-power
amateur operation into load VSWRs as
high as 1.5:1. However, the amplifier
may easily be user-programmed to
optimize operation with VSWRs up to
2:1, on non-amateur frequencies, and
at various power levels.
 Capable of full CW break-in (QSK) and
all digital modes when used with any
appropriate transceiver. All front panel
functions plus numerous other
diagnostic and control functions are
accessible via its RS-232
communications port.
 Protective functions built in. The
microprocessor-based control system
incorporates protective functions that
minimize the probability of accidental
damage to the amplifier or its power
tubes. In most cases, when one of the
protective functions is “tripped,” front
panel LED indicators display a fault
code, which indicates the nature of
the problem, (e.g. excessive grid or
plate current, load VSWR, etc.)
 AlphaMax firmware comes with added
features to readjust output network, trim
tune-up time, and re-adjust loading to
prevent distortion due to overdrive.
 AlphaRemote software lets you to control
all functions of your Alpha 87A from a
compact toolbar on your Windows
desktop.
 Optional auxiliary cooling fan available.
We recommend using the external

auxiliary fan for extended RTTY or other
“locked key” service. This is available
separately from Alpha Radio Products.
 Capable of no more than 150 watts into a
50dB load in bypass mode.
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Alpha 87A User Manual Rev 2.0

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Alpha 87A User Manual Rev 2.0
Section
3
ALPHA 87A Specifications
NOTE:
FCC rules do not permit new amateur amplifiers to be operable on 24-30 MHz as delivered
within the US and possessions. Owners who send Alpha Technical Support a photocopy of
their authorizing amateur license will promptly be provided information on “unlocking” 12 and
10 meter coverage..
Band Change & Tuning: Automatic under
microprocessor control; average time required for
complete band change and tune-up, <1 second.
No special cables or connections required.
Frequency Coverage: All amateur bands 1.8-29.7
MHz* plus most non-amateur frequencies 6.0-19.0
MHz and 20-30 MHz.
Power Output: 1500 watts PEP, keyed CW, or
continuous carrier, no time limit. Auxiliary cooling
fan (optional) recommended for very high duty
cycle continuous operation i.e. contesting & RTTY.
Drive Power: Typically 50 to 55 watts for full rated
output.
Input VSWR: < 1.5:1 within amateur bands; < 2:1
elsewhere.
Tube Complement: Two Eimac 3CX800A7
triodes in grounded grid.
T/R System: Heavy-duty PIN diode switch capable
of feed through and hot switching of 150W exciter
power. Switching time approximately 1ms.
Enclosed mechanical bypass relay.
ALC: Grid-current-derived, -10V maximum,
adjustable gain.
Harmonic Output: Better than 50 dB below rated
output.
Intermodualtion: Better than 35 dB below rated
output.
Fault Protection: Plate current, grid current, load
VSWR, T/R sequencing, gain (i.e., severe mistune
or RF arc), overdrive, open heater, over
temperature, others.
Displays: LED bar graphs for peak Pout, Prefl & Ig,
and switched bar graph for Ip, HV, and Tune
indicator.
Cooling: Full cabinet ducted air, rear intake/top
exhaust. Floating blower mount for quietest
operation.
Primary Power: 190-250V (200, 220, 240V
nominal taps), 50-60 Hz, single phase; fused 20A.
Size & Weight: 17.3” W x 7”H x 16.5” D (439 x
178 x 419 mm) excluding controls, feet, and
connectors. 75 lb. (34kg) net.
Note: Alpha Radio Products reserves the right to
change design and/or specifications without prior
notice or obligation.

Page 12
Figures 1-3 Transformer
Installation
Alpha 87A User Manual Rev 2.0

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Alpha 87A User Manual Rev 2.0
Section
4
Unpacking and Preparing for
Operation
(Refer to Figures. 1-5, pages 6, 8, 9)
4.1 Carefully unpack amplifier and
transformer. Inspect both for physical
damage. Save all packing material for future
use.
4.2 Remove cover by removing all screws
except the two located in the perforated tube
exhaust areas. Inspect carefully for shipping
damage. Check all connectors for proper
seating. If damage is discovered, call Alpha
Technical Support immediately.
4.3 Remove blower motor shipping hardware
from rear chassis wall. Save the two 10-32
bolts, fiber washers, and rubber shim; reinstall
this hardware whenever the chassis is
transported. NOTE: For heavy-duty use or
50 Hz operation, the optional auxiliary fan
must be installed.
4.4 Connect the proper internal line voltage
tap. The ALPHA 87A may be operated from
any AC power source of 190-250V, 50-60 Hz,
20-ampere capacity. It is advisable to check
the actual voltage at the connector you are
going to use for the Alpha 87A. Use an
accurate meter such as a DMM set to AC
volts. A 4-terminal barrier strip for tap
selection is located atop the AC module to the
left of the transformer, approximately where
the arrow points in fig. 1A. DO NOT MOVE
the wire connected to the terminal marked
PRI! If necessary, move the other wire to the
tap (200, 220, or 240V) closest to your
nominal AC line voltage. (Amplifiers for US
distribution destinations normally are shipped
connected for 240V input.)
4.5 Install Transformer. Position amplifier flat
on a table with the right side of the chassis
facing forward. Install the transformer per
Figures 1 through 3, using its wire handle.
Use care not to damage wiring or

Page 14
components. You may wish to have a helper
steady the chassis during the following two
steps. (Bolts must be installed for safe
operation!)
Align the transformer captive nuts with
corresponding chassis holes. Taking care not
to torque or twist the chassis, carefully extend
it over the edge of the table just far enough to
loosely screw in the two outside transformer-
mounting bolts (1/4-20 hex head with flat
washers, supplied).
Do not stand the amplifier on edge or move it
further over the table edge. Instead, rotate it
so as to install the bolts. Now center the
transformer as much as possible so that both
sides are well clear of metalwork. Move
chassis as above while tightening all 4 bolts.
Inspect the connectors on the transformer to
be sure there is nothing blocking the
connector holes, such as pieces of shipping
materials. One of the transformer’s
connectors plugs into the AC power module
near the top/rear of the chassis center
partition, on the power supply side. Another
connector plugs into the low voltage power
supply board, which is immediately in front of
the transformer near the chassis floor.
A third (HVAC) connector plugs into the HV
board in front of the transformer and up high.
(See Fig. 3 and views A-A and B-B). Make
certain the connectors are properly mated and
seated, but don’t force them; they mate and
latch easily.
4.6 Insure that both tubes are fully seated in
their sockets with their red rubber chimneys
firmly contacting the chassis.
4.7 Make sure the HV crowbar works
smoothly.
4.8 Replace the cover and carefully
reinstall all screws. Be careful not to force
or cross thread the screws. Never use
screws longer than ¼”! (Screws supplied are
¼”).
Do not attempt to operate the amplifier with
the cover removed. This could cause
damage to the Alpha 87A or you.
Alpha 87A User Manual Rev 2.0

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Figure 4 – Inside Top View
Alpha 87A User Manual Rev 2.0

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Figure 5 – Front Panel
Lowered
Alpha 87A User Manual Rev 2.0

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Figure 6 - Inside Front
Panel
Alpha 87A User Manual Rev 2.0

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Figure 7 - Rear Panel
Alpha 87A User Manual Rev 2.0

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Alpha 87A User Manual Rev 2.0
Section
5
Control and Indicator
Functions
5.1 RF OUTPUT, GRID CURRENT and
REFLECTED POWER bargraphs are peak-
reading and generally self-explanatory.
Example: 1.5 kW output (forward power into
a 50 ohm load) is indicated when all green
LED segments to the left of the 1.5 (kW) label
are fully lighted and the first red LED segment
is barely illuminated. The primary calibration
point for RF OUTPUT is at 1.5 kW on 14
MHz. Accuracy of the meter is approximately
10%.
5.2 TUNE/IP/HV “multimeter”: The function
of this indicator is selected by buttons at its
right. It is a moving-dot display. HV (plate
voltage) is read on the 0-3 kV top scale and Ip
(plate current) on the 0-1.5 A bottom scale.
The TUNE meter function permits fast and
safe manual tuning and loading of the
amplifier at reduced power (Sec. 7.3)
5.3 BAND and SEGMENT buttons: Each
band (tuning range) is represented by a
button with indicator LED on the upper left
front panel. On each band, five memory
channels, or segments, are provided for
factory programmed tuning data and five for
user (field) programmed data. On the front
panel, five SEGMENT buttons with LED
indicators correspond to these band
segments as detailed below.
BAND or SEGMENT buttons are not used
during routine operation because the ALPHA
87A automatically switches bands and tunes
up, if necessary, upon application of RF drive.
BAND and SEGMENT buttons may, however,
be used before applying drive to avoid the
brief amplifier bypass, which occurs during
automatic band change with drive applied.
When a new BAND is selected manually, the
amplifier automatically selects the segment
last used on that band unless a different
SEGMENT button is pushed. To protect
against improper tuning, the ALPHA 87A
automatically overrides any improper manual
band or segment selection upon application of
drive.
The SEGMENT buttons and the row of
buttons below them also are used in field
programming of the ALPHA 87A as
described later.
Each BAND button is labeled with the nominal
(MHz) frequency of the principal amateur
band covered within its tuning range.
Labeling below each SEGMENT button
indicates its factory programmed frequency
coverage relative to the frequency in MHz
shown below the BAND button. As may be
deduced, on all bands except 1.8 and 28 MHz
segment center frequencies are factory turned
at 100 kHz spacing; 1.8 MHz segments are
spaced 40 kHz, 28MHz segments 400 kHz.
5.5 Factory Programming: Each segment is
factory (default) programmed so that the

Page 20
ALPHA 87A will deliver 1.5 kW output (into a
50-ohm load of VSWR of <1.5:1) efficiently
across the frequency range indicated under
that SEGMENT button.
Example: Using default (factory) tuning with
the “14” (BAND, MHz) button and the number
3 SEGMENT button illuminated, ALPHA 87A
tuning is centered at 14.250 MHz for optimum
performance from approximately 14.2 to 14.3
MHz. Panel labeling shows the nominal
edges of factory segments in the 1.8 and 28
MHz bands. Actual segment coverages
overlap somewhat to prevent “hunting”.
5.6 User Programming, TUNE & LOAD
buttons: The ALPHA 87A may be user-tuned
at any five different center frequencies in each
band; the five SEGMENT buttons may be
assigned to these frequencies in any desired
order, as explained in Section 7.2. The TUNE
and LOAD buttons are used during user
programming.
Each segment is identified in memory by its
center frequency and nominal width. During
automatic segment selection the amplifier
seeks first the nearest user segment centered
within 50 kHz of the drive frequency (10M,
+200 kHz) then such a factory segment. If
neither exists it selects the nearest segment.
5.7 DEFAULT button: May be used to
override automatically selected user tuneup
data for a segment and instead “default” to
factory data.
5.8 ENTER button: Used in conjunction with
SEGMENT buttons to memorize user-tuning
data. (See Section 7.)
5.9 Special rear-panel connections: (See
figure 7, opposite)
ALC & ALC Adjust – See sections 7.1 & 10.2.
IG & PFWD – Provide d-c signal outputs
proportional to grid current and power output,
respectively.
KEY OUT – Provides a pull-down to ground
(through 47 ohm resistor) which follows the
line connected to the RELAY jack when the
amplifier is ON and in OPERATE condition.
When the 87A is in STANDBY or OFF, KEY
OUT is directly connected to the RELAY jack
by a closed relay contact I the amplifier.
Useful for special T/R hook-ups when
amplifier is used with exciters having poor T/R
sequencing. Contact Alpha Power Customer
Support for specific advice.
J1-RS-232 communications link; see Section
9.Figure 7 Rear Panel Connections
Alpha 87A User Manual Rev 2.0