70W HF Power Amplifier 3.5-30MHz AB Class Shortwave Linear Amp for Transceiver QRP Radio Receiver Transmitter SSB/CW/AM/FM Modes

3-30MHz – 70W HF Shortwave Power Amplifier for FT-817 – High Frequency Linear Amplifier (Assembled Unit)Attention: The board has encapsulated electronic adhesive that is more reliable and secureWarning:The input and output must be plugged in before powering on. Otherwise, the chip will be burned because reflected signal is too large.If the operation is improper Please bear the responsibility yourselfProduct Description:This 70W HF linear power amplifier covers 3–30MHz (shortwave band) and is ideal for boosting low‑power transceivers like the FT-817. It operates from DC 13.8V (max 18V) and delivers up to 70W output at 7MHz (18V supply gives >70W on lower bands). The board includes a PTT control (short to transmit), an onboard reserved LPF loop for external low‑pass filters, and a fan header (fan not included). The module is compact (9×5×4.5cm) and comes fully assembled. A cooling fan is required during operation due to high power dissipation.Specifications:Frequency Range: 3 – 30 MHz (HF)Operating Voltage: DC 13.8V (absolute max 18V)Max Current: Input Power: Output Power: 70W @ 7MHz (at 13.8V); >70W on lower bands at 18V supplyDimensions: 9 × 5 × 4.5 cmConnections:RF input (IN), RF output (OUT), VCC (+), GND (−), PTT (short totransmit), FAN (2‑pin header), LPF‑IN/OUT (for external low‑passfilter), JP1 jumper (closed = internal path, open = use external filter)Key Features:High efficiency linear amplifier for HF bandsPTT control for transmit/receive switchingReserved LPF ports for external band‑pass filtering (reduce harmonics)Fan header for active cooling (fan not included)Compact size, ready to useIncluded: Assembled amplifier board (bare board, no fan, no heat sink or enclosure unless specified).Important Notes:A cooling fan is mandatory during operation – the amplifier generates significant heat.Do not exceed 18V supply voltage.Use a suitable low‑pass filter at the output to meet harmonic emission standards (external LPF can be connected via LPF‑IN/OUT).Applications:Boosting low‑power QRP transceivers (e.g., FT-817, FT-818, IC-705)Amateur radio (HAM) home and field operationHF digital modes (FT8, PSK31) and SSB/CWDIY HF station setupEmergency communication systems