W1XMRadome

radio - [Radome]

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T01:28:49+00:00

Overview The RF systems of the radome allow it to fulfill multiple operating modes: * Radio astronomy telescope (receive-only on 1420 MHz) * Satellite uplink (half-duplex on 440 MHz) * Amateur radio (half-duplex on 440 MHz, 1296 MHz, and others)

radome_loss_table.png - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T01:28:19+00:00

mit_bldg_54_biu_faap_115313-0008-00_final_radome_calculations.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T00:39:41+00:00

cpi_radome_technical_manual_-_7-19-22.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T00:39:41+00:00

radome_transmission_loss.png - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T00:38:12+00:00

start - [Structure of Radome Systems]

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T00:33:23+00:00

Radome Wiki [Installation of the new radome on November 5, 2022. Taken by Ron Hoffmann, N1XU.] The radome is a 27-foot composite sphere (Essco S27-83) on the roof of MIT building 54 containing an 18-foot circular radar dish on an SCR-584 alt-azimuth radar rotor. It is owned and operated by the MIT UHF Repeater Association W1XM but used for a variety of purposes including:

software - [RF Data Handling]

dsheen (dsheen@undisclosed.example.com) — 2026-05-18T00:06:12+00:00

Controlling the Dish The dish control server program runs on w1xm-radar-1.mitrs.org and is used by all software that controls the dish. Features include: - WebSockets-based protocol making use from Python, JavaScript, etc. client programs easy - Support for multiple coordinate reference frames, as well as automatic tracking of the sky

1420mhzfeed - [1420 MHz]

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T23:43:05+00:00

1420 MHz The 1420 MHz frontend is a receive-only system designed by Daniel Sheen (KC1EPN) for radio astronomy. It is tuned to 1420 MHz for the hydrogen emission line and incorporates custom bandpass filters to reject high power OOB signals which otherwise overload the LNAs. The LNAs used are the first generation Indium Phosphide devices designed for the deep synoptic array, and incorporate noise calibration diodes which are used for amplitude and phase calibration of the full RX chain.

electrical - [Power]

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T23:37:22+00:00

Overview The electrical systems of the radome documented here are for power and control. See the Overview section for the RF systems. Power There are 3-phase mains power circuits which are wired into the radome pedestal for powering motor drives and RF power amplifiers. They are controlled by the disconnect switches on the wall in 54-2101, which have lock-out-tag-out safety systems to prevent RF and motor power being switched on while people are working on the radome. See the

getting-started - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T23:33:05+00:00

Getting Started 1. read this site...

safety

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T23:13:55+00:00

The radome poses a risk of high RF field exposure and of crushing from the moving dish. To prevent these hazards, a keyed interlock system attached to the 3-phase power disconnects power to the RF power amplifiers and the motor drives. The 2 keys (A and B) on the disconnects in 54-2101 are required to open the radome hatch, and they cannot be removed from 54-2101 without turning off the disconnects. This ensures power to the dish drives is disabled, and that the dish has had time to fully stop …

1296mhzfeed - [1296 MHz Feed]

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T23:07:32+00:00

1296 MHz Feed The 1296 MHz feed is an amateur radio feed intended for Earth-Moon-Earth (transmit and receive, half-duplex). It is a scaling of the design for the 1420 MHz Feed. The accepted convention within the amateur radio community for Earth-Moon-Earth (EME) communication is to transmit using right-hand-circular polarization (RHCP) and receive using left-hand-circular polarization (LHCP), since reflection off the Moon flips the polarization.

wr66_rotary_coupler.zip - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:59:44+00:00

copy_of_03oct2022_cmt_ulna_data_ganesh_to_daniel.xlsx - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:50:13+00:00

measurements.zip - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:45:48+00:00

new_phasecal_coefficients.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:40:26+00:00

polarimetric_fits_import.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:35:06+00:00

polarimeter_phase_calibration.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T22:33:11+00:00

6_meter_dish_2024_001_antenna_pattern_modelling_and_measurement_overview.pdf - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T21:51:43+00:00

big_dish_beam_pattern.jpg - created

dsheen (dsheen@undisclosed.example.com) — 2026-05-17T21:42:50+00:00