The Harry D. Powell Observatory Radio Telescope

Specifications
      ETSU's radio telescope located at The Harry D. Powell Observatory is the newest addition to the array of instruments.  The radio telescope was purchased in 2001 and became operational in the spring of 2004.  It was purchased with the aid of a NASA Education/Public Outreach Grant.  The radio telescope will be used as an educational tool for the freshman Astronomy I & II courses, for summer workshops for local middle and high school teachers, and will also serve as an outreach tool for regional high school students. (See Outreach at left.)

     The Haystack Observatory at the Massachusetts Institute of Technology developed the original Small Radio Telescope (SRT).  For information about purchasing an SRT kit follow the link at left to the SRT Hompage.

Check back later for the latest developments with our radio telescope.  There are many plans for the future!!!
Labs
Operation
(Instructions for lab instructors and students are now available.  More will be posted soon.)
Outreach
Haystack Observatory
SRT Home Page
ETSU Powell Observatory
ETSU Physics, Astronomy, and Geology Dept
Various Pictures






Specifications
Our radio telescope consists of a digital L-band (1.42 GHz) reciever mounted at the focus of a 10 foot diameter parabolic reflecting antenna.  The digital receiver provides a total bandwidth of 430 MHz and a total approximate beamwidth of 4.9 degrees.  This large beamwidth combined with the specialized control software allows the telescope to be used for a wide variety of tasks including total power measurements from celestial sources and contour mapping of large regions of the sky.  Below are some of the more technical specifications of the reciever.

Digital Receiver

L.O. Frequency range 1370-1800 MHz
L.O. Tuning steps 40 kHz
L.O. Settle time <5 ms
Rejection of LSB image >20 dB
Bandwidth/Resolution Modes 1200/8 kHz*
(Currently supported in ver 1.0 firmware) 500/8 kHz
- 250/4 kHz
- 125/2 kHz
I.F. Center 800 kHz
6 dB I.F. range 0.5-3 MHz
Preamp frequency range 1400-1440 MHz
Typical system temperature 150K
Typical L.O. leakage out of preamp -105dBm
Preamp input for dB compression
from out of band signals		 -24 dBm
Preamp input for intermodulation interference -30 dBm
Control RS-232 2400 baud
* The 1200 kHz wideband is synthesized using 3 500 kHz bands stitched together from a frequency scan.


Labs
Measuring the Beamwidth of the Radio Telescope:
This lab allows the student to learn about several properties of the radio telescope and lets them measure the beamwidth of the telescope using the Sun as a radio source.  Students are then asked to compare this beamwidth with that of optical telescopes.
If you would like a copy of this lab, please contact Dr. Beverly Smith.




Outreach
We hope to have our outreach effort to local schools in place soon.  It is our goal to make the radio telescope available to local classes via VNC (Virtual Network Computing) .  This would make the telescope available to classes for long-term projects lasting a period of weeks or months.  Such projects could include galactic cloud mapping, galactic rotation curve calculations, or observations of more distant objects like M31 (Andromeda galaxy).

Stay tuned for more information or email faculty for the latest developments with this program.  Tentatively we would like to have this in place by next fall.


Pictures
This is the antenna (the dish) along with the receiver mounted at the focus.


In this photo the polar mounting arrangement can clearly be seen.


Here we have the control system inside the observatory.

The control system consists of three pieces:
  1. a PC running Windows® 2000
  2. the silver ground control box which relays information to and from the outdoor equipment
  3. the JAVA® based control software
 

Operation Instructions
Below you will find links to an assortment of documents detailing operation of the telescope.  Most of the documents are written as if one is setting at the console at the observatory.  If you have connected remotely by VNC then the telescope will (should) be powered up and operational, and all other documents will apply.  Some of these documents were written by us and some by the folks at the Haystack Observatory. 

How To:

Other Documentation from Haystack Observatory


Last updated 4/8/08 by B. J. Smith