Project Leader: Jeroen, PE1RGE
"Demeter" is the project-name for the HPSDR power supply. Allthough power supplies are widely available, Demeter will be specifically designed for the HPSDR project.
At this moment, 11th of June 2007, an inventory of wishes, specifiactions and ideas is made for the HPSDR-power supply. If you have any ideas, questions or suggestions, please feel free to E-mail me.
Further information will be presented on this page when it becomes available.
73 Jeroen PE1RGE
First result of the discussion on the HPSDR mailing-list (11th June 2007):
Input 13.8 Volt DC (always 13.8 V or is there a supply range, see remark below) 110 Vac (mains) 230 Vac (mains) Battery (13.8Volt) input with automatic switchover Input connector Powerpole connector for DC 13.8 Volt Mains connector: National standard Output voltages Remote switchable voltages +5 Volt @ …. Amps + 12 Volt @ ….. Amps -12 Volt @ ….. Amps Standby supply (for GPS-engine and OCXO) Constant on + 5 Volt + 15 Volt + 24 Volt (depends on OCXO used, if possible user definable/adjustable)
Output connector ATX-connector DIN 41612 (Atlas connectors) Protection Input protection (high/low voltage, polarity) Output protection (current limiting, voltage crowbar)
Monitoring · Input voltage · Output voltage · Output currents · Temperature
Power supply communication Atlas backplane USB-bus 1 wire interface (controlled by a board on Atlas) Dumb-interface using the pins T7 and T8 on the Atlas
Connection to the HPSDR Using the ATX power connector, communication via the USB bus Using the DIN41612 connector using the Atlas backplane for communication
Position of the power supply On the Atlas backplane In a separate box (outside/inside Pandora)
HPSDR configuration Ozymandias - interface module Mercury – receiver (5V @ 500mA, 12V @ 200mA, -12V not used) Penelope – transmitter (5V @ 300mA, 12V @ 200mA, -12V not used)) Alexiares - RF Bandpass Filters Gibraltar - frequency standard Epimetheus - antenna and other switching
Measured: Ozy + Janus: +12v @ 200mA, +5v @ 180 ma, -12v @ 70 ma
Questions/remarks Switching or Lineair? Internal/External? Power dissipation (Convection cooling/ forced air-cooling)? Do we need computer monitoring of voltages and currents? Include an USB-HUB (use one of the ports for the power supply communication)? Configuration (to use or not to use the SDR-1000)? People who use it in combination with the SDR-1000 need less power from the power-supply and are using a custom built supply or the SRD-1000 power supply. Will the 13.8Volt really be 13.8Volt or “something” between 11.0 Volt and 15 Volt? With other words: How many people are going to use the HPSDR mobile?
Linear (A “lot of heat”, not “green”, easy to construct and trouble-shoot)
Switching (Less heat, more “green”, more noise, more difficult to construct)
Transformers: From my opinion there will always be a normal mains-transformer, both in the switching and the linear power supply option. Building a switcher for 110Vac/230Vac is too dangereous and complicated (safety regulations) for (less experienced) home-builders. The switcher will be situated in the low-voltage part.