It's a 15W CW/10W AM transmitter for the 40m / 20m bands, based on G3OGR - OM F.G. Rayer's
article 'QRP Transmitter for the LF Bands' published in the August 1971 issue of 'Practical Wireless'
magazine.
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| 15W CW/10W AM Transmitter for 7/14 MHz |
ECC81 - VFO on 3.5 MHz
EF89 - Buffer
EF89 - Multiplier to 7 MHz
EF89 - Multiplier to 14 Mhz
EL86 - Final with Pi tank
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| 15W CW / 10W AM Transmitter for 7/14 MHz - top inside |
It has a companion power supply cum modulator.
The modulator stages are as follows:
ECC83 - Speeech Amplifier
EL84 - Modulator
Here are the design manuscripts:
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| Transmitter |
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| Transmitter Schematic |
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| Power Supply cum Modulator |
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| Power Supply Schematic |
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| Modulator Schematic |
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| Transmitter - Instructions |
Using this transmitter, a number of CW DX stations (including a 'W' on 40m) were worked in the late 1970s. AM DX contacts were also made with 4S7 and YB0 stations.
Only simple dipole antennas were used.
Related post: A Homebrew 100W (DC Input) Class 'C' Amplifier
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