This amplifier is designed to work with the current HPSDR Penelope transmitter assembly to amplify the signal of max. 500 mW to 100 Watts RF output. It was designed to operate from 160m up to and including 6m in all HF Amateur bands in all modes. See Photos 2, 3, & 4 for as built schematic drawings.
All parts are included including a drilled and tapped 185 X130 X 25 mm heatsink (see photo above). The parts are mailed in two packages. The first package has the heatsink, hardware, toroids, wire, fuse, flat ribbon cable, ribbon connectors, and relays. An overall enclosure is not included.
Functions and Features:
The amplifier uses a four layer circuit board, which makes possible optimum impedance match of all the HF circuit board lines. The Amplifier is installed onto an Aluminum heat sink by the user. Dimensions LxWxH are185 x 130 x 50mm. Cooling fans may be required by the user depending upon type of mounting and the planned duty cycle of usage. Connections to the optional PWR/SWR meter and the HPSDR Pentelope transmit exciter board starts on the Amplifier's printed circuit board via a single flat strip cable. By programming the on board CPLD, additional interfaces can be implemented.
Operating voltages are 12-14 Volts with current input to a maximum of 25 Amperes, HF-power output is 100W PEP on 160-10m, and 50W on 6m.
Frequency range: 1.8MHz to 52MHz with 7 bandpass filters for 160m, 80m, 60/40m, 30/20m, 17/15m, 12/10m and 6m. Designed for max. transmission and min. return, the band pass filters use single-aperture cores and SMD mica capacitors with high Q and min. losses. The bandpass filters can alternatively be used only in the transmit mode or in the transmission and receive mode. The selection takes place via selection of a CPLD program by means of a circuit board jumper.
Monitoring of the operational data is accomplished by using an Atmega CONTROLLER and the data is indicated on an optional 4 parameter LCD. The selection of limit values and selection of the display mode take place via 3 keys under the display as follows:
• Temperature measurement at the heat sink to the nearest degree C
• Set point for the start-up of cooling fans is adjustable from 50 to 80°C
• Set points for the limits for switch off the amplifier is adjustable from 60 to 90°C
• Fan Hysteresis is 10°C (in firmware).
• Indicator for power input 0-25A.
• Current limit for switching off Amplifier adjustable from 7 to 25A
• FWD_PWR measurement in Watts
• REV_PWR measurement in Watts
• SWR measurement to one right-of-comma position.
• Limit for switching the final stage off adjustable with SWR greater than 1,5 to 3
Hercules Build Instructions:
1. Wind 28 turns of .35 mm dia. enameled wire on to a (red) T50-2 toroid. Cut and tin the leads at about 1/2" below the toroid. This coil will be designated L1 at 4 UH.
2. Wind 28 turns of .35 mm dia. enameled wire on to a (red) T50-2 toroid. Cut and tin the leads at about 1/2" below the toroid. This coil will be designated L2 at 4 UH.
3. Wind 17 turns of .8 mm dia. enameled wire on to a (red) T50-2 toroid. Cut and tin the leads at about 1/2" below the toroid. This coil will be designated L3 at 1.5 UH.
4. Wind 19 turns of .8 mm dia. enameled wire on to a (red) T50-2 toroid. Cut and tin the leads at about 1/2" below the toroid. This coil will be designated L4 at 1.8 UH.