SECTION 1 - INTRODUCTION
1.1 General Description
The
ALPHA 86
is a self-contained, HF linear power amplifier capable of continuous operation at a
power output of 1500 watts PEP, keyed CW, SSTV, RTTY, or AM, with no time limit (rated for continuous
commercial service, "CCS"). Units delivered within the USA and its territories and possessions are manually
tunable over the frequency range of 1.8 to 22 MHz. They may be user-modified to extend coverage to 29.7
MHz. Units delivered elsewhere cover 1.8 through 30 MHz. Performance is optimized for amateur bands.
The
ALPHA 86
is capable of high-speed, full break-in CW (QSK) when used with a suitably-designed
transceiver. Note: the term "transceiver" includes suitable transmitter-receiver combinations, such as the
Collins S-Line and Drake R4C-T4XC, etc. The
ALPHA 86
is fully compatible with CW, AMTOR, or PACKET
modes.
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Specifications
1.2.1 Frequency Coverage: 1.8-22 MHz (domestic units); 1.8-30 MHz (export units).
1.2.2 Power Output: 1500 watts all modes including continuous carrier, CCS.
1.2.3 Drive Power: 50 to 70 watts nominal for rated output.
1.2.4 Power Gain: approximately 15 dB, equivalent to a power increase of thirty times.
1.2.5 Input Impedance: 50 ohms nominal, unbalanced VSWR < 2:1; switched pi-networks for each band.
1.2.6 Output Impedance: 50 ohms unbalanced.
1.2.7 Maximum Load VSWR: 2:1 at full rated power output.
1.2.8 VSWR Trip: automatic for reflected power of >200 watts.
1.2.9 Intermodulation Distortion: 35 db below rated output.
1.2.10 Harmonic Output: < -55 dBc amateur bands; < -50 dBc elsewhere.
1.2.11 CW Break-in (QSK): PIN diode T/R switching, 4 millisecond maximum switching time.
1.2.12 Tube Complement: two Eimac 3CX800A7 ceramic-metal triodes.
1.2.13 Cooling: full cabinet ducted forced air using cushion-mounted centrifugal blower.
1.2.14 Automatic Level Control (ALC): negative-going (from zero) DC voltage derived as a function of
grid current. May be used to limit exciter output to prevent amplifier overdrive.
1.2.15 Primary Power: 220-240 volts AC, 60Hz (50-60 Hz export and non-type accepted models), fused
at 20 amperes. May be field-modified for 110-120 volt operation at reduced power (maximum
fuse size 20 amperes).
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