Summary of AM shortwave transmitter
This article details an 8 Watt QRP AM shortwave transmitter project by Station QRP, intended for educational purposes in RF design. It emphasizes legal compliance, requiring operation only with a dummy load and prohibiting unlicensed antenna use. The circuit utilizes specific vacuum tubes for the oscillator and power amplifier stages, powered by a high-tension supply. Parts are noted as available from surplus retailers or salvageable from old radio sets.
Parts used in the 8 Watt QRPAM Shortwave Transmitter:
- Oscillator tube 6BX6 (UK = EF80)
- Power Amplifier tube 6CJ6 or 6DR6 (UK=EL81)
- HT Power Supply providing 300 Volts at 300 mA
- Dummy load for safe operation
IMPORTANT: The published circuit diagrams of Station QRP are for educational purposes only. These are offered for the furtherance of the readers’ knowledge regarding Radio Frequency design and principles. At all times during operation an assembled unit must be connected to a dummy load.
In most countries law prohibits the unlicensed operation of transmitters w hen connected to an antenna or even to have such equipment
present in a fully or partially installed state. All responsibilities for the ultimate use of the diagrams are bornesolely by the
builder and/or operator
8 Watt QRPAM Shortwave Transmitter Are you interested in building this 8 WattAM shortwave transmitter?
Most parts used in this transmitterare still available (e.g. Surplus Sales of Nebraska http://www.surplussales.com)o
r can be salvaged from old radio communicationsets. If you wish to purchasea ready-builtonec ontact me viawww.stationqrp.com for details. QRPAM Shortwave Transmitter Technical Data Transmitter: Tube(UK=Valve)
-Oscillator 6BX6 (UK = EF80) -Power Amplifier 6CJ6 or 6DR6 (UK=EL81) HT Power Supply:300 Voltsat300 mA
For more detail: AM shortwave transmitter
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What is the purpose of the published circuit diagrams?
The diagrams are for educational purposes to further readers' knowledge regarding Radio Frequency design and principles. -
How must an assembled unit be connected during operation?
An assembled unit must always be connected to a dummy load during operation. -
Does law prohibit unlicensed operation of transmitters?
Yes, in most countries, law prohibits unlicensed operation when connected to an antenna or having equipment present in an installed state. -
Who bears responsibility for the ultimate use of the diagrams?
All responsibilities for the ultimate use of the diagrams are borne solely by the builder and/or operator. -
Where can parts for this transmitter be obtained?
Most parts are still available from Surplus Sales of Nebraska or can be salvaged from old radio communication sets. -
Can I purchase a ready-built version of this transmitter?
Yes, you can contact the author via www.stationqrp.com for details on purchasing a ready-built one.
