AMERITRON AL-80B, Инструкция по эксплуатации

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AL-80B Instruction Manual
9
The continuous commercial plate current rating of the 3-500Z is 400 mA. For maximum tube life,
plate current should be maintained below 400 mA on CW and other "steady" carrier modes. Brief
periods of plate current exceeding 400 mA will not cause loss of emission or shorten the life of the
tube in this amplifier.
The application of filament voltage causes thermal stresses from rapid and uneven temperature
changes. Needless cycling of the filament may cause premature failure or unnecessary stress in the
tube's filament.
An accumulation of gas (or stray debris) in the tube can cause arcs between the anode and the other
elements of the tube. The resulting "gas arc" will generally manifest itself as a loud "pop" when the
amplifier is first turned on. A "gas arc" will often damage diode D117 on the negative rail of the
filter capacitor bank and open the fuses in the amplifier. If this problem occurs frequently, the tube
should be tested or replaced. The use of low quality tubes, tubes that have been stored for extended
periods, or abused tubes increase likelihood of a "gas arc". Ameritron recommends using only
current code date Eimac 3-500Z tubes.
Export Modifications
A simple modification will allow operation on frequencies above 15 meters. Instructions for this
modification are available by sending a written request for "Export Modification Instructions" along
with a copy of a valid amateur license. There is no charge for this information. Export models are
shipped with this modification installed and have an "X" or "Y" following the serial number.
Standard frequency ranges are indicated in the chart on page 29.
Technical Assistance
Technical assistance is available during normal central standard time business hours on weekdays.
Customer service is more effective when our engineers are provided the following information:
1. Model and serial number
2. Date of purchase and dealer
3. An accurate description of the problem
Meter readings at all stages of the tuning procedure are very important along with a complete
description of the other equipment used with our product.
Written assistance is also available. Due to time delays in processing mail, please allow at least
three weeks for a written reply. For service or written correspondence, use the following address:
AMERITRON
116 Willow Road
Starkville, MS 39759
Telephone (662) 323-8211
FAX (662) 323-6551
NOTE:
Service history has clearly shown that most problems are operating or installation
errors, rather than equipment failures. Most problems can be resolved over the
telephone. Please contact our staff before shipping parts or equipment to us.