1. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 1 Feed & Front End PDR Solar Observing

2. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 2 Solar Power Levels 1 SFU = 10 4 Jy = 1250 Kelvins at VLA Max. flare = 100,000 SFU “Normal” Tsys ~ 25 K = 0.02 SFU Max/Normal = 67 dB range. Receivers & Tcal must accept 67 dB range.

3. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 3 Solar Block Diagram

4. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 4 Power Levels in Solar Receiver

5. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 5 Signal-to-Noise Ratio, etc.

6. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 6 New Components Required “High Compression” amplifier (2) Isolators (3) Transfer switch (2) Noise amplifier (1) Cal step attenuator (1) 20 dB “solar” attenuator (2)

7. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 7 New Components Required—Cost Note: very rough guess! L-band (1-2 GHz)$3k/antenna X-band (8-12 GHz)$5k/antenna Q-band (40-50 GHz)$20k/antenna Cost not included in plan

8. Paul LilieFeed & Front End PDR-Solar 12-13 Feb 2002 8 May require solar cal on all antennas. Need accurate cal values at all levels. Need phase-invariant switching. Converter ALC range > 20 dB. ALC attenuators move to front of converters.