㰀搀椀瘀 椀搀㴀∀栀攀愀搀攀爀∀㸀㰀戀爀 ⼀㸀 㰀℀ⴀⴀ 㰀愀 栀爀攀昀㴀∀栀琀琀瀀㨀⼀⼀眀眀眀⸀攀搀洀漀渀琀漀渀爀愀猀挀⸀挀漀洀∀㸀㰀栀㌀㸀䠀漀洀攀㰀⼀栀㌀㸀㰀⼀愀㸀 ⴀⴀ㸀 㰀⼀搀椀瘀㸀 㰀℀ⴀⴀ 㰀椀洀最 猀爀挀㴀∀椀洀愀最攀猀⼀栀攀愀搀攀爀⸀樀瀀最∀ 眀椀搀琀栀㴀∀㜀㤀 ∀ 栀攀椀最栀琀㴀∀㈀㈀㠀∀ 愀氀琀㴀∀∀ ⼀㸀 ⴀⴀ㸀 㰀搀椀瘀 椀搀㴀∀愀瘀洀攀渀甀∀㸀 This article appeared in the February, 1999 edition of the Journal of the Royal Astronomical Society of Canada
㰀栀㌀㸀䄀戀猀琀爀愀挀琀㰀⼀栀㌀㸀Building a simple radio telescope is relatively easy with a combination of persistence and the right help. Surplus satellite television equipment can be modified to permit radio observations of the Sun and Moon and introduce the user to the fundamentals of radio astronomy. This article describes the steps taken by the author to assemble a radio telescope and the results of his observations.
㰀栀㌀㸀䤀渀琀爀漀搀甀挀琀椀漀渀㰀⼀栀㌀㸀Between December 1997 and April 1998 I assembled a simple radio telescope that was able to observe solar radiation at radio frequencies. The telescope consists of a used satellite television (TV) system in the 12 GHz (Ku) band that was constructed with guidance via E-mail from William Lonc, professor emeritus of physics at Saint Mary s University in Halifax, Nova Scotia. My experiences may be helpful to others wishing to take beginning steps in the interesting field of radio astronomy.
㰀瀀㸀吀栀攀 攀砀攀爀挀椀猀攀 愀氀氀漀眀攀搀 洀攀 琀漀 爀攀欀椀渀搀氀攀 椀渀琀攀爀攀猀琀猀 椀渀 戀漀琀栀 愀猀琀爀漀渀漀洀礀 愀渀搀 攀氀攀挀琀爀漀渀椀挀猀 琀栀愀琀 眀攀爀攀 愀戀愀渀搀漀渀攀搀 眀栀攀渀 䤀 眀愀猀 愀 琀攀攀渀愀最攀爀 椀渀 漀爀搀攀爀 琀漀 瀀甀爀猀甀攀 漀琀栀攀爀 挀愀爀攀攀爀 最漀愀氀猀⸀ 䴀甀挀栀 栀愀猀 挀栀愀渀最攀搀 猀椀渀挀攀 䤀 眀漀爀欀攀搀 眀椀琀栀 瘀愀挀甀甀洀 琀甀戀攀猀 愀渀搀 最愀稀攀搀 愀琀 匀愀琀甀爀渀 琀栀爀漀甀最栀 愀 ㌀ⴀ椀渀挀栀 爀攀昀爀愀挀琀漀爀⸀ 䄀琀 愀最攀 昀漀爀琀礀 愀渀搀 爀攀昀氀攀挀琀椀渀最 漀渀 氀椀昀攀 愀琀 琀栀椀猀 猀琀愀最攀 漀昀 洀愀琀甀爀椀琀礀Ⰰ 䤀 眀愀猀 爀攀愀搀礀 琀漀 爀攀瘀椀猀椀琀 琀栀攀 愀眀攀 䤀 昀攀氀琀 愀猀 愀 琀攀攀渀愀最攀爀 攀砀瀀氀漀爀椀渀最 愀渀 甀渀猀攀攀渀 瀀愀爀琀 漀昀 漀甀爀 眀漀爀氀搀⸀㰀⼀瀀㸀Failed FM Radio Telescope
㰀瀀㸀䴀礀 昀椀爀猀琀 爀愀搀椀漀 愀猀琀爀漀渀漀洀礀 瀀爀漀樀攀挀琀 戀攀最愀渀 椀渀 䐀攀挀攀洀戀攀爀 㤀㤀㜀 甀猀椀渀最 愀 猀琀愀渀搀愀爀搀 栀漀洀攀 猀琀攀爀攀漀 䘀䴀 爀攀挀攀椀瘀攀爀 愀爀爀愀渀最攀洀攀渀琀 戀愀猀攀搀 漀渀 愀 搀攀猀椀最渀 搀攀猀挀爀椀戀攀搀 戀礀 䐀愀瘀椀搀 䰀⸀ 䠀攀椀猀攀爀洀愀渀 椀渀 栀椀猀 戀漀漀欀 刀愀搀椀漀 䄀猀琀爀漀渀漀洀礀 昀漀爀 琀栀攀 䄀洀愀琀攀甀爀 ⠀䠀攀椀猀攀爀洀愀渀 㤀㜀㔀⤀⸀ 䤀琀 眀愀猀 渀漀琀 猀甀挀挀攀猀猀昀甀氀Ⰰ 瀀攀爀栀愀瀀猀 戀攀挀愀甀猀攀 漀昀 洀礀 氀愀挀欀 漀昀 攀砀瀀攀爀椀攀渀挀攀⸀ 䈀甀椀氀搀椀渀最 愀 ㌀㐀ⴀ昀漀漀琀 夀愀最椀 愀渀琀攀渀渀愀 洀漀甀渀琀攀搀 椀渀 洀礀 戀愀挀欀礀愀爀搀Ⰰ 愀渀搀 洀攀愀猀甀爀椀渀最 琀栀攀 渀漀椀猀攀 椀琀 瀀椀挀欀攀搀 甀瀀Ⰰ 搀攀洀漀渀猀琀爀愀琀攀搀 樀甀猀琀 栀漀眀 洀甀挀栀 琀攀爀爀攀猀琀爀椀愀氀 椀渀琀攀爀昀攀爀攀渀挀攀 琀栀攀爀攀 椀猀 椀渀 琀栀攀 爀愀搀椀漀 猀瀀攀挀琀爀甀洀⸀ 嘀愀爀礀椀渀最 栀漀甀猀攀栀漀氀搀 氀椀渀攀 瘀漀氀琀愀最攀猀 琀漀 琀栀攀 爀攀挀攀椀瘀攀爀Ⰰ 挀漀甀瀀氀攀搀 眀椀琀栀 椀渀琀攀爀昀攀爀攀渀挀攀Ⰰ 洀愀搀攀 椀琀 椀洀瀀漀猀猀椀戀氀攀 琀漀 漀戀猀攀爀瘀攀 琀栀攀 匀甀渀 椀渀 琀栀攀 挀漀洀洀攀爀挀椀愀氀 䘀䴀 戀愀渀搀⸀ 䤀 氀攀愀爀渀攀搀 琀栀愀琀Ⰰ 椀渀 愀搀搀椀琀椀漀渀 琀漀 愀洀戀椀攀渀琀 氀椀最栀琀Ⰰ 愀洀戀椀攀渀琀 爀愀搀椀漀 琀爀愀渀猀洀椀猀猀椀漀渀猀 愀氀猀漀 栀椀渀搀攀爀 琀栀攀 漀戀猀攀爀瘀愀琀椀漀渀 漀昀 愀猀琀爀漀渀漀洀椀挀愀氀 猀漀甀爀挀攀猀⸀㰀⼀瀀㸀
㰀瀀㸀䈀礀 琀栀攀 攀渀搀 漀昀 䐀攀挀攀洀戀攀爀Ⰰ 䤀 挀漀渀挀氀甀搀攀搀 琀栀愀琀 䤀 渀攀攀搀攀搀 琀漀 琀爀礀 愀 搀椀昀昀攀爀攀渀琀 琀愀挀欀⸀ 䤀昀 琀栀攀 䘀䴀 戀愀渀搀 眀愀猀 渀漀琀 最漀椀渀最 琀漀 眀漀爀欀Ⰰ 眀栀愀琀 昀爀攀焀甀攀渀挀礀 猀栀漀甀氀搀 䤀 甀猀攀㼀 匀漀洀攀 戀漀漀欀猀 䤀 猀挀愀渀渀攀搀 愀渀搀 愀 挀漀甀瀀氀攀 漀昀 爀愀搀椀漀 愀猀琀爀漀渀漀洀攀爀猀 䤀 猀瀀漀欀攀 眀椀琀栀 瘀椀愀 䔀ⴀ洀愀椀氀 猀甀最最攀猀琀攀搀 瘀愀爀椀漀甀猀 昀爀攀焀甀攀渀挀椀攀猀 昀漀爀 猀攀瘀攀爀愀氀 愀渀琀攀渀渀愀 愀渀搀 爀攀挀攀椀瘀攀爀 挀漀渀昀椀最甀爀愀琀椀漀渀猀⸀ 䔀ⴀ洀愀椀氀 挀漀渀瘀攀爀猀愀琀椀漀渀猀 搀椀爀攀挀琀攀搀 洀攀 琀漀 琀栀攀 㘀 䴀䠀稀 漀爀 㐀㈀ 䴀䠀稀 ⠀琀栀攀 栀礀搀爀漀最攀渀 氀椀渀攀 昀爀攀焀甀攀渀挀礀⤀ 戀愀渀搀猀⸀ 䈀甀琀 琀栀攀爀攀 眀攀爀攀 攀渀漀甀最栀 漀瀀琀椀漀渀猀 琀漀 戀攀 挀漀渀昀甀猀椀渀最⸀ 䄀 挀漀甀瀀氀攀 漀昀 瀀攀漀瀀氀攀 猀甀最最攀猀琀攀搀 琀栀愀琀 䤀 挀漀渀琀愀挀琀 圀椀氀氀椀愀洀 䰀漀渀挀 愀渀搀 爀攀愀搀 栀椀猀 戀漀漀欀 刀愀搀椀漀 䄀猀琀爀漀渀漀洀礀 倀爀漀樀攀挀琀猀 ⠀䰀漀渀挀 㤀㤀㘀⤀⸀ 䤀 挀漀渀琀愀挀琀攀搀 䈀椀氀氀 瘀椀愀 䔀ⴀ洀愀椀氀⸀ 䠀攀 琀漀氀搀 洀攀 琀漀 爀攀愀搀 琀栀攀 戀漀漀欀 昀椀爀猀琀Ⰰ 琀栀攀渀 琀愀氀欀 眀椀琀栀 栀椀洀 愀戀漀甀琀 瀀爀漀樀攀挀琀猀⸀ 䤀琀 瀀爀漀瘀攀搀 琀漀 戀攀 最漀漀搀 愀搀瘀椀挀攀⸀ 伀渀挀攀 䤀 爀攀愀搀 琀栀攀 戀漀漀欀Ⰰ 栀攀 猀甀最最攀猀琀攀搀 琀栀愀琀 琀栀攀 猀椀洀瀀氀攀猀琀 眀愀礀 琀漀 最攀琀 猀琀愀爀琀攀搀 眀愀猀 琀漀 愀搀愀瀀琀 愀 猀愀琀攀氀氀椀琀攀 吀嘀 猀礀猀琀攀洀 愀渀搀 琀漀 搀漀 猀漀氀愀爀 漀戀猀攀爀瘀愀琀椀漀渀猀⸀ 吀栀愀琀 戀攀挀愀洀攀 洀礀 最漀愀氀⸀㰀⼀瀀㸀 A Satellite Radio Telescope
㰀瀀㸀䘀椀渀搀椀渀最 愀 猀愀琀攀氀氀椀琀攀 猀礀猀琀攀洀 眀椀琀栀椀渀 洀礀 戀甀搀最攀琀 眀愀猀 琀栀攀 昀椀爀猀琀 栀甀爀搀氀攀⸀ 䄀昀琀攀爀 琀攀氀攀瀀栀漀渀椀渀最 愀 渀甀洀戀攀爀 漀昀 爀攀琀愀椀氀 猀愀琀攀氀氀椀琀攀 吀嘀 戀甀猀椀渀攀猀猀攀猀 愀渀搀 猀甀爀瀀氀甀猀 礀愀爀搀猀 氀漀漀欀椀渀最 昀漀爀 甀猀攀搀 搀椀猀栀攀猀 愀渀搀 爀攀挀攀椀瘀攀爀猀Ⰰ 䤀 爀攀愀挀栀攀搀 漀渀攀 猀愀琀攀氀氀椀琀攀 吀嘀 戀甀猀椀渀攀猀猀 琀栀愀琀 最愀瘀攀 洀攀 愀 最漀漀搀 氀攀愀搀⸀ 䄀 猀琀愀昀昀 洀攀洀戀攀爀 椀渀昀漀爀洀攀搀 洀攀 琀栀愀琀 吀栀攀 倀攀漀瀀氀攀ᤀ 猀 一攀琀眀漀爀欀 ⠀吀倀一⤀Ⰰ 愀 戀爀漀愀搀挀愀猀琀攀爀 猀攀氀氀椀渀最 猀攀氀昀ⴀ栀攀氀瀀 瀀爀漀最爀愀洀洀椀渀最 瘀椀愀 猀愀琀攀氀氀椀琀攀Ⰰ 栀愀搀 爀攀挀攀渀琀氀礀 猀眀椀琀挀栀攀搀 椀琀猀 䌀愀渀愀搀椀愀渀 猀甀戀猀挀爀椀戀攀爀猀 漀瘀攀爀 昀爀漀洀 愀渀愀氀漀最 琀漀 搀椀最椀琀愀氀 爀攀挀攀椀瘀攀爀 猀礀猀琀攀洀猀⸀ 吀栀愀琀 洀攀愀渀琀 琀栀攀爀攀 眀愀猀 愀 猀甀瀀瀀氀礀 漀昀 爀攀氀愀琀椀瘀攀氀礀 椀渀攀砀瀀攀渀猀椀瘀攀 甀猀攀搀 䌀 漀爀 䬀甀 戀愀渀搀 攀焀甀椀瀀洀攀渀琀 氀礀椀渀最 愀爀漀甀渀搀⸀㰀⼀瀀㸀I contacted the local TPN representative, who was happy to give me the names of five people who wanted to sell their systems. I found one for $210. It included most of the features I needed: a 1.2-metre dish with azimuth and elevation mount, a Low Noise Block (LNB) converter at the focal point of the offset dish, transmission line, and switchable C and Ku band receiver.
㰀椀洀最 猀爀挀㴀∀椀洀愀最攀猀⼀戀氀漀挀欀⸀樀瀀最∀ 圀椀搀琀栀㴀∀㐀㔀 ∀ 愀氀琀㴀∀䈀氀漀挀欀 搀椀愀最爀愀洀 漀昀 猀礀猀琀攀洀∀ ⼀㸀My enthusiasm got the better of me, because I purchased the system without verifying that it had a signal strength meter or Automatic Gain Control (AGC) mechanism in the receiver. Either of the two features is necessary in order to observe signal variations from astronomical sources. Signal strength meters can be found on many FM stereo receiver systems. They are used to indicate when the receiver is tuned to a station. Most take the form of a meter that deflects proportionally to signal strength. Others can be a single or series of LEDs that light as the signal increases.
㰀瀀㸀吀栀攀 爀攀挀攀椀瘀攀爀 䤀 瀀甀爀挀栀愀猀攀搀 栀愀搀 愀 猀椀渀最氀攀 䰀䔀䐀 琀栀愀琀 眀愀猀 愀昀昀攀挀琀攀搀 戀礀 挀栀愀渀最椀渀最 琀栀攀 挀栀愀渀渀攀氀 琀甀渀椀渀最 漀渀 琀栀攀 昀爀漀渀琀 漀昀 琀栀攀 爀攀挀攀椀瘀攀爀⸀ 䤀琀 瀀爀漀瘀攀搀 琀漀 栀愀瘀攀 猀漀洀攀 漀琀栀攀爀 愀猀ⴀ礀攀琀ⴀ甀渀搀攀琀攀爀洀椀渀攀搀 瀀甀爀瀀漀猀攀 甀渀爀攀氀愀琀攀搀 琀漀 猀椀最渀愀氀 猀琀爀攀渀最琀栀Ⰰ 愀渀搀 眀愀猀 琀栀攀爀攀昀漀爀攀 漀昀 渀漀 栀攀氀瀀 琀漀 洀攀⸀ 䤀渀 漀琀栀攀爀 眀漀爀搀猀Ⰰ 琀栀攀 爀攀挀攀椀瘀攀爀 栀愀搀 渀漀 猀椀最渀愀氀 猀琀爀攀渀最琀栀 洀攀琀攀爀⸀㰀⼀瀀㸀I had to find some other way of detecting signal strength. Sometimes satellite TV systems have a connection on the rear of the receiver that installers use to determine when they have located the satellite signal. This is called the Automatic Gain Control (AGC). Unfortunately, my receiver had no exterior AGC connection either.
㰀瀀㸀吀栀愀琀 昀漀爀挀攀搀 洀攀 琀漀 氀漀漀欀 椀渀猀椀搀攀 琀栀攀 爀攀挀攀椀瘀攀爀 椀琀猀攀氀昀 昀漀爀 愀 猀椀最渀愀氀 猀琀爀攀渀最琀栀 挀漀渀渀攀挀琀椀漀渀⸀ 吀栀攀 爀攀挀攀椀瘀攀爀 椀猀 渀漀琀 愀 挀漀洀洀漀渀 戀爀愀渀搀 ⠀嘀椀搀攀漀 倀氀甀猀⤀Ⰰ 愀渀搀 䤀 眀愀猀 甀渀愀戀氀攀 琀漀 氀漀挀愀琀攀 猀挀栀攀洀愀琀椀挀猀 漀爀 琀栀攀 漀爀椀最椀渀愀氀 洀愀渀甀昀愀挀琀甀爀攀爀⸀ 䤀 猀瀀漀欀攀 眀椀琀栀 猀攀瘀攀爀愀氀 猀愀琀攀氀氀椀琀攀 吀嘀 猀甀瀀瀀氀椀攀爀猀Ⰰ 愀渀搀 攀瘀攀渀琀甀愀氀氀礀 昀漀甀渀搀 猀漀洀攀漀渀攀 眀栀漀 猀甀最最攀猀琀攀搀 琀栀愀琀 䤀 挀栀攀挀欀 琀栀攀 琀甀渀攀爀 椀渀猀椀搀攀 琀栀攀 爀攀挀攀椀瘀攀爀⸀ 吀栀攀 琀甀渀攀爀 椀猀 愀 猀洀愀氀氀 洀攀琀愀氀 戀漀砀 昀愀猀琀攀渀攀搀 漀渀 琀栀攀 椀渀猀椀搀攀 漀昀 琀栀攀 挀愀猀攀 愀琀 琀栀攀 戀愀挀欀 漀昀 琀栀攀 甀渀椀琀⸀ 吀栀攀 琀爀愀渀猀洀椀猀猀椀漀渀 氀椀渀攀 挀漀渀渀攀挀琀猀 琀漀 琀栀攀 戀漀砀 昀爀漀洀 琀栀攀 䰀一䈀 漀渀 琀栀攀 搀椀猀栀⸀㰀⼀瀀㸀Satellite tuners generally have up to twelve pin connectors used for different functions within the receiver. The satellite technician suggested that I experiment with them to locate the AGC circuit. At Bill Lonc s suggestion, I first connected the system to a TV set to make sure the system was in fact able to detect a satellite signal. It was able to pick up several satellite channels, and I began the process of testing the pins using the satellite signal to evaluate the purpose of each pin.
㰀瀀㸀圀椀琀栀 琀栀攀 吀嘀 猀攀琀 渀攀愀爀 琀栀攀 搀椀猀栀Ⰰ 䤀 甀猀攀搀 琀栀攀 吀嘀 瀀椀挀琀甀爀攀 愀渀搀 猀漀甀渀搀 愀猀 愀 眀愀礀 漀昀 瘀攀爀椀昀礀椀渀最 眀栀攀琀栀攀爀 琀栀攀 搀椀猀栀 眀愀猀 瀀漀椀渀琀攀搀 漀渀 漀爀 漀昀昀 猀椀最渀愀氀 愀猀 䤀 洀漀瘀攀搀 琀栀攀 搀椀猀栀⸀ 䄀 瘀漀氀琀洀攀琀攀爀 眀愀猀 挀漀渀渀攀挀琀攀搀 戀攀琀眀攀攀渀 琀栀攀 挀栀愀猀猀椀猀 最爀漀甀渀搀 漀昀 琀栀攀 爀攀挀攀椀瘀攀爀 愀渀搀 攀愀挀栀 瀀椀渀 椀渀 琀甀爀渀⸀ 䤀 琀栀攀渀 琀漀漀欀 洀攀琀攀爀 爀攀愀搀椀渀最猀 昀漀爀 攀愀挀栀 瀀椀渀 眀栀攀渀 琀栀攀 搀椀猀栀 眀愀猀 瀀漀椀渀琀攀搀 漀渀 愀渀搀 漀昀昀 猀椀最渀愀氀⸀ 匀漀洀攀 栀愀搀 渀漀 瘀漀氀琀愀最攀Ⰰ 猀漀洀攀 猀栀漀眀攀搀 挀漀渀猀琀愀渀琀 瘀漀氀琀愀最攀Ⰰ 愀渀搀 猀漀洀攀 瘀愀爀椀攀搀 搀攀瀀攀渀搀椀渀最 漀渀 眀栀攀琀栀攀爀 琀栀攀礀 眀攀爀攀 漀渀 漀爀 漀昀昀 猀椀最渀愀氀⸀㰀⼀瀀㸀Focusing on the three pins with variable voltages, I refined the investigation by connecting a digital voltmeter with a serial interface to a data-logging program on our home computer. That allowed the output from each pin to be graphed in turn as the dish was moved slowly from an off signal position, through the signal (on), past the signal to an off position again. One pin produced an erratic behaviour, another gave a strong response to the satellite, and the third produced a mild but consistent response.
㰀瀀㸀䈀攀挀愀甀猀攀 琀栀攀 猀椀最渀愀氀 昀爀漀洀 愀 瀀漀椀渀琀 猀漀甀爀挀攀 猀甀挀栀 愀猀 琀栀攀 匀甀渀 椀猀 欀渀漀眀渀 琀漀 挀爀攀愀琀攀 愀 戀攀氀氀 猀栀愀瀀攀搀 挀甀爀瘀攀 眀栀攀渀 瀀愀猀猀椀渀最 琀栀爀漀甀最栀 琀栀攀 戀攀愀洀 漀昀 愀渀 愀渀琀攀渀渀愀Ⰰ 䤀 愀猀猀甀洀攀搀 琀栀愀琀 椀昀 䤀 最漀琀 愀 猀椀最渀愀氀 椀渀 琀栀攀 猀栀愀瀀攀 漀昀 愀 戀攀氀氀 挀甀爀瘀攀Ⰰ 䤀 洀甀猀琀 栀愀瘀攀 昀漀甀渀搀 琀栀攀 䄀䜀䌀 挀椀爀挀甀椀琀⸀ 吀栀攀 猀椀最渀愀氀猀 瀀爀漀搀甀挀攀搀 椀渀 琀栀攀 昀椀爀猀琀 猀攀爀椀攀猀 漀昀 最爀愀瀀栀攀搀 琀攀猀琀猀 眀攀爀攀 愀昀昀攀挀琀攀搀 戀礀 琀栀攀 樀攀爀欀礀 洀漀琀椀漀渀 漀昀 琀栀攀 搀椀猀栀Ⰰ 猀椀渀挀攀 琀栀攀 搀椀猀栀 眀愀猀 洀漀瘀攀搀 洀愀渀甀愀氀氀礀⸀ 吀栀愀琀 爀攀渀搀攀爀攀搀 琀栀攀 搀愀琀愀 椀渀挀漀渀挀氀甀猀椀瘀攀⸀ 䈀攀挀愀甀猀攀 吀嘀 猀愀琀攀氀氀椀琀攀猀 愀爀攀 最攀漀猀琀愀琀椀漀渀攀爀礀 愀渀搀 爀攀焀甀椀爀攀 洀愀渀甀愀氀 洀漀瘀攀洀攀渀琀 漀昀 琀栀攀 搀椀猀栀 琀漀 氀漀挀愀琀攀 琀栀攀 猀椀最渀愀氀Ⰰ 猀愀琀攀氀氀椀琀攀猀 眀攀爀攀 渀漀琀 愀 猀愀琀椀猀昀愀挀琀漀爀礀 洀攀琀栀漀搀 漀昀 攀瘀愀氀甀愀琀椀渀最 琀栀攀 猀礀猀琀攀洀 爀攀猀瀀漀渀猀攀 漀渀 琀栀攀 琀栀爀攀攀 瀀椀渀猀⸀㰀⼀瀀㸀The Sun
㰀瀀㸀䤀琀 眀愀猀 琀椀洀攀 琀漀 琀爀礀 愀渀 漀戀猀攀爀瘀愀琀椀漀渀 漀昀 琀栀攀 匀甀渀⸀ 吀栀攀 匀甀渀 椀猀 愀 猀琀爀漀渀最 猀漀甀爀挀攀 漀昀 爀愀搀椀漀 猀椀最渀愀氀猀⸀ 吀栀攀爀攀 眀攀爀攀 愀 挀漀甀瀀氀攀 漀昀 眀愀礀猀 琀漀 甀猀攀 椀琀 愀猀 愀 猀椀最渀愀氀 琀漀 瘀攀爀椀昀礀 眀栀椀挀栀 漀昀 琀栀攀 琀栀爀攀攀 瀀椀渀猀 眀愀猀 琀栀攀 漀渀攀 䤀 眀愀渀琀攀搀⸀ 䤀琀 愀氀猀漀 渀椀挀攀氀礀 挀漀椀渀挀椀搀攀搀 眀椀琀栀 洀礀 最漀愀氀 漀昀 漀戀猀攀爀瘀椀渀最 琀栀攀 匀甀渀⸀㰀⼀瀀㸀Transit observations are a common and inexpensive way for amateur radio astronomers to observe celestial sources in the radio spectrum. By pointing the antenna southward along the north/south meridian at a particular elevation and allowing the sky to pass in front of the antenna beam, the observer can correlate detected signals with astronomical objects. A variation on the meridian transit method is to point the antenna just ahead of a known source and allow the rotation of the Earth to move the source through the antenna beam. With more expensive equipment it is possible to track objects across the sky all the time observing their radio emission.
㰀瀀㸀一漀琀 栀愀瘀椀渀最 愀 琀爀愀挀欀椀渀最 猀礀猀琀攀洀Ⰰ 䤀 甀猀攀搀 琀栀攀 琀爀愀渀猀椀琀 洀攀琀栀漀搀 琀漀 昀椀渀搀 琀栀攀 䄀䜀䌀 瀀椀渀 漀渀 琀栀攀 琀甀渀攀爀⸀ 吀栀攀 搀椀猀栀 眀愀猀 愀椀洀攀搀 樀甀猀琀 猀氀椀最栀琀氀礀 愀栀攀愀搀 漀昀 琀栀攀 匀甀渀 愀渀搀 琀栀攀 爀攀猀瀀漀渀猀攀 漀渀 攀愀挀栀 漀昀 琀栀攀 琀栀爀攀攀 瀀椀渀猀 眀愀猀 爀攀挀漀爀搀攀搀 愀猀 琀栀攀 匀甀渀 瀀愀猀猀攀搀 琀栀爀漀甀最栀 琀栀攀 愀渀琀攀渀渀愀 戀攀愀洀⸀ 吀栀攀 瀀椀渀 琀栀愀琀 栀愀搀 戀攀栀愀瘀攀搀 攀爀爀愀琀椀挀愀氀氀礀 戀攀昀漀爀攀 搀椀搀 琀栀攀 猀愀洀攀 琀栀椀渀最 琀栀椀猀 琀椀洀攀Ⰰ 愀渀搀 琀栀攀 漀渀攀 琀栀愀琀 爀攀猀瀀漀渀搀攀搀 猀琀爀漀渀最氀礀 琀漀 琀栀攀 猀愀琀攀氀氀椀琀攀 猀栀漀眀攀搀 渀漀 爀攀猀瀀漀渀猀攀⸀ 吀栀攀 琀栀椀爀搀 瀀椀渀 猀栀漀眀攀搀 愀 猀琀攀瀀瀀攀搀 爀攀猀瀀漀渀猀攀Ⰰ 椀渀挀爀攀愀猀椀渀最 愀猀 琀栀攀 匀甀渀 瀀愀猀猀攀搀 琀漀 琀栀攀 挀攀渀琀爀攀 漀昀 琀栀攀 戀攀愀洀Ⰰ 琀栀攀渀 搀攀挀氀椀渀椀渀最 愀猀 椀琀 瀀愀猀猀攀搀 漀甀琀 漀昀 琀栀攀 戀攀愀洀⸀ 䤀 栀愀搀 昀漀甀渀搀 琀栀攀 䄀䜀䌀Ⰰ 愀渀搀 挀漀椀渀挀椀搀攀渀琀愀氀氀礀 漀戀猀攀爀瘀攀搀 琀栀攀 匀甀渀 昀漀爀 洀礀 昀椀爀猀琀 琀椀洀攀⸀㰀⼀瀀㸀After the three months I spent determining a suitable frequency, finding a satellite system, and getting it operational for radio astronomy purposes, it was a tremendous thrill to finally see some results. With an optical telescope the results are immediate, and the observable sources are more or less unlimited. Someone interested in radio astronomy needs to have a curiosity for the mechanics of radio observing to stay interested.
㰀栀㌀㸀刀攀昀椀渀椀渀最 琀栀攀 伀戀猀攀爀瘀愀琀椀漀渀猀㰀⼀栀㌀㸀The accuracy of my first observation was not very good, as evidenced by the stepped nature of the graph where the voltage moved from a baseline of 2.65 volts, to 2.66 volts, then peaked at 2.67. The voltmeter was set to 20 volts dc. The next lowest setting is 2 volts. It was not possible to use the 2-volt range because the output voltage of around 2.65 volts direct current (Vdc) would have overloaded the meter. On the other hand, the lower range would have allowed better accuracy with more significant digits.
㰀椀洀最 猀爀挀㴀∀椀洀愀最攀猀⼀猀甀渀⸀樀瀀最∀ 圀椀搀琀栀㴀∀㐀㔀 ∀ 愀氀琀㴀∀䈀氀漀挀欀 搀椀愀最爀愀洀 漀昀 猀礀猀琀攀洀∀ ⼀㸀The high range setting meant the signal could theoretically have varied between a low of 11 millivolts and a high of 29 millivolts. At the 20-volt setting, the actual signal strength could have reached 29 millivolts by varying between 2.645 volts (rounded up to 2.65 because of the setting) and 2.674 volts (rounded down to 2.67). Inversely, it could have been 6 millivolts, with possible low and high readings spread between 2.665 volts and 2.654 volts. Each such reading would yield the same graphical results.
㰀瀀㸀䄀猀 愀 爀攀猀甀氀琀Ⰰ 琀栀攀 猀椀最渀愀氀 猀琀爀攀渀最琀栀 挀漀甀氀搀 渀漀琀 戀攀 搀攀琀攀爀洀椀渀攀搀 愀挀挀甀爀愀琀攀氀礀 愀琀 琀栀攀 猀攀琀琀椀渀最 䤀 眀愀猀 甀猀椀渀最⸀ 䄀渀漀琀栀攀爀 甀渀挀攀爀琀愀椀渀琀礀 眀愀猀 眀栀攀琀栀攀爀 漀爀 渀漀琀 䤀 栀愀搀 瀀漀椀渀琀攀搀 琀栀攀 搀椀猀栀 愀挀挀甀爀愀琀攀氀礀⸀ 䐀椀搀 琀栀攀 匀甀渀 瀀愀猀猀 琀栀爀漀甀最栀 琀栀攀 挀攀渀琀爀攀 漀昀 琀栀攀 愀渀琀攀渀渀愀ᤀ 猀 戀攀愀洀Ⰰ 漀爀 琀栀爀漀甀最栀 琀栀攀 猀椀搀攀 漀昀 琀栀攀 戀攀愀洀㼀 䤀昀 琀栀攀 搀椀猀栀 眀愀猀 瀀漀椀渀琀椀渀最 漀昀昀ⴀ挀攀渀琀爀攀 琀漀 愀渀礀 攀砀琀攀渀琀Ⰰ 琀栀攀 猀琀爀攀渀最琀栀 漀昀 琀栀攀 猀椀最渀愀氀 眀漀甀氀搀 戀攀 氀漀眀攀爀⸀ 䄀氀猀漀Ⰰ 琀栀攀 最爀愀瀀栀 漀昀 琀栀攀 猀椀最渀愀氀 搀椀搀 渀漀琀 氀漀漀欀 氀椀欀攀 琀栀攀 渀椀挀攀 戀攀氀氀 挀甀爀瘀攀 琀栀愀琀 眀漀甀氀搀 戀攀 攀砀瀀攀挀琀攀搀 眀椀琀栀 愀 洀漀爀攀 昀椀渀攀氀礀 最爀愀搀攀搀 猀挀愀氀攀 愀琀 琀栀愀琀 昀爀攀焀甀攀渀挀礀⸀ 䤀渀猀琀攀愀搀Ⰰ 椀琀 氀漀漀欀攀搀 氀椀欀攀 愀 挀爀漀漀欀攀搀 氀椀琀琀氀攀 猀琀椀氀攀 漀瘀攀爀 愀 挀爀漀漀欀攀搀 氀椀琀琀氀攀 昀攀渀挀攀⸀㰀⼀瀀㸀To solve the problem, a second observation was conducted. I attached a 100 K ohm potentiometer between the chassis ground of the receiver and the AGC pin, and read the signal between the centre-tap and ground of the potentiometer. By adjustment of the potentiometer, the baseline voltage could be offset to below 2 Vdc, making readings at the 2-volt setting significant to three decimal places rather than to the two places I was able to read at a setting of 20 volts.
㰀瀀㸀吀栀攀 猀攀挀漀渀搀 漀戀猀攀爀瘀愀琀椀漀渀 猀栀漀眀攀搀 愀 猀洀漀漀琀栀 戀攀氀氀 挀甀爀瘀攀Ⰰ 戀甀琀 愀琀 渀漀琀 愀猀 猀琀爀漀渀最 愀 猀椀最渀愀氀 愀猀 䤀 栀愀搀 攀砀瀀攀挀琀攀搀⸀ 吀栀攀 挀椀爀挀甀椀琀 挀甀琀 瀀愀爀琀 漀昀 琀栀攀 琀漀琀愀氀 猀椀最渀愀氀 爀攀猀瀀漀渀猀攀 漀昀昀 愀琀 琀栀攀 琀漀瀀 攀渀搀 漀昀 琀栀攀 瀀漀琀攀渀琀椀漀洀攀琀攀爀⸀ 匀椀渀挀攀 猀椀最渀愀氀猀 昀爀漀洀 愀猀琀爀漀渀漀洀椀挀愀氀 猀漀甀爀挀攀猀 愀爀攀 攀砀琀爀攀洀攀氀礀 猀洀愀氀氀Ⰰ 猀椀最渀愀氀 氀漀猀猀 栀愀猀 琀漀 戀攀 愀瘀漀椀搀攀搀 愀琀 愀氀氀 挀漀猀琀猀⸀㰀⼀瀀㸀The peak signal over the baseline voltage that I obtained using the potentiometer was 20 mV. After doing some calculations of projected signal loss at the top end of the potentiometer, I concluded that the system could probably produce a maximum signal of approximately 30 mV over the baseline. For a satisfactory number of significant digits, that would require use of some other means other than the potentiometer to drop the voltage to a level readable at the meter setting of 2-volts. The results correlated nicely with the maximum signal that was possible within the limits of uncertainty associated with the first observation.
㰀瀀㸀伀渀挀攀 愀最愀椀渀 䈀椀氀氀 䰀漀渀挀 挀愀洀攀 琀漀 琀栀攀 爀攀猀挀甀攀Ⰰ 眀椀琀栀 愀 猀椀洀瀀氀攀 挀椀爀挀甀椀琀 搀攀猀椀最渀 琀栀愀琀 愀氀氀漀眀攀搀 洀攀 琀漀 搀爀漀瀀 琀栀攀 戀愀猀攀氀椀渀攀 瘀漀氀琀愀最攀 昀甀爀琀栀攀爀Ⰰ 琀漀 琀栀攀 瀀漀椀渀琀 眀栀攀爀攀 䤀 眀愀猀 愀戀氀攀 琀漀 甀猀攀 琀栀攀 ㈀ 洀嘀 猀攀琀琀椀渀最 漀渀 琀栀攀 洀攀琀攀爀Ⰰ 琀栀椀猀 琀椀洀攀 眀椀琀栀漀甀琀 猀椀最渀愀氀 氀漀猀猀⸀ 䈀椀氀氀ᤀ 猀 挀椀爀挀甀椀琀 甀猀攀猀 琀眀漀 ⸀㔀 瘀漀氀琀 䐀 挀攀氀氀 戀愀琀琀攀爀椀攀猀 愀渀搀 愀 瀀漀琀攀渀琀椀漀洀攀琀攀爀 戀攀琀眀攀攀渀 琀栀攀 最爀漀甀渀搀Ⰰ 洀攀琀攀爀Ⰰ 愀渀搀 䄀䜀䌀 瀀椀渀 琀漀 挀愀渀挀攀氀 愀瀀瀀爀漀砀椀洀愀琀攀氀礀 ㈀⸀㔀 瘀漀氀琀猀⸀ 吀栀攀 猀椀最渀愀氀 瘀漀氀琀愀最攀 挀漀甀氀搀 琀栀攀渀 戀攀 瘀椀攀眀攀搀 愀最愀椀渀猀琀 愀 瘀攀爀礀 氀漀眀 戀愀猀攀氀椀渀攀 瘀漀氀琀愀最攀⸀ 䤀 眀愀猀 愀戀氀攀 琀漀 爀攀愀搀 愀 猀椀最渀愀氀 漀昀 ㌀ 洀嘀 漀瘀攀爀 琀栀攀 戀愀猀攀氀椀渀攀Ⰰ 挀漀渀昀椀爀洀椀渀最 琀栀攀 攀砀瀀攀挀琀攀搀 瘀愀氀甀攀 ⸀ 䈀攀挀愀甀猀攀 漀昀 琀栀攀 瘀漀氀琀愀最攀 挀愀渀挀攀氀椀渀最 挀椀爀挀甀椀琀Ⰰ 䤀 眀愀猀 愀戀氀攀 琀漀 甀猀攀 琀栀攀 ㈀ 洀嘀 猀攀琀琀椀渀最 漀渀 琀栀攀 瘀漀氀琀洀攀琀攀爀⸀ 䄀琀 琀栀愀琀 猀攀琀琀椀渀最 琀栀攀 猀礀猀琀攀洀 眀愀猀 猀攀渀猀椀琀椀瘀攀 攀渀漀甀最栀 琀漀 爀攀挀漀爀搀 猀椀最渀愀氀 瘀愀爀椀愀琀椀漀渀猀 昀爀漀洀 瘀椀戀爀愀琀椀漀渀猀 漀昀 琀栀攀 搀椀猀栀 愀猀 䤀 眀愀氀欀攀搀 愀挀爀漀猀猀 琀栀攀 搀攀挀欀 眀栀椀氀攀 琀栀攀 匀甀渀 瀀愀猀猀攀搀 琀栀爀漀甀最栀 琀栀攀 愀渀琀攀渀渀愀 戀攀愀洀⸀ 一漀琀攀 琀栀攀 琀栀爀攀攀 戀甀洀瀀猀 漀渀 琀栀攀 戀攀氀氀 挀甀爀瘀攀 挀愀甀猀攀搀 戀礀 瘀椀戀爀愀琀椀漀渀 漀昀 琀栀攀 搀椀猀栀⸀㰀⼀瀀㸀
㰀瀀㸀吀栀攀 戀攀愀洀 漀昀 愀 瀀愀爀愀戀漀氀椀挀 搀椀猀栀 愀渀琀攀渀渀愀 挀漀渀猀椀猀琀猀 漀昀 愀 挀漀渀攀ⴀ猀栀愀瀀攀搀 愀爀攀愀 椀渀 昀爀漀渀琀 漀昀 琀栀攀 愀渀琀攀渀渀愀 昀爀漀洀 眀栀椀挀栀 爀愀搀椀漀 眀愀瘀攀猀 挀愀渀 戀攀 搀攀琀攀挀琀攀搀⸀ 吀栀攀 ⸀㈀ⴀ洀 搀椀猀栀 栀愀搀 愀 瀀爀攀搀椀挀琀攀搀 戀攀愀洀眀椀搀琀栀 漀昀 ㈀ﴀ﷿ 䄀渀琀攀渀渀愀 戀攀愀洀眀椀搀琀栀 渀漀爀洀愀氀氀礀 猀瀀攀挀椀昀椀攀猀 琀栀攀 愀渀最甀氀愀爀 搀椀猀琀愀渀挀攀 戀攀琀眀攀攀渀 琀栀攀 瀀漀椀渀琀猀 眀栀攀爀攀 琀栀攀 猀椀最渀愀氀 爀攀愀挀栀攀猀 栀愀氀昀 椀琀猀 猀琀爀攀渀最琀栀 漀渀 攀椀琀栀攀爀 猀椀搀攀 漀昀 琀栀攀 瀀攀愀欀 猀椀最渀愀氀 ⠀爀攀昀攀爀爀攀搀 琀漀 愀猀 ∀栀愀氀昀 瀀漀眀攀爀 瀀漀椀渀琀猀∀⤀⸀ 䴀礀 漀戀猀攀爀瘀愀琀椀漀渀猀 栀愀搀 愀 瘀愀爀椀攀琀礀 漀昀 猀椀最渀愀氀 椀渀挀爀攀愀猀攀猀 琀栀愀琀 搀攀瀀攀渀搀攀搀 氀愀爀最攀氀礀 漀渀 眀栀攀琀栀攀爀 漀爀 渀漀琀 琀栀攀 匀甀渀 瀀愀猀猀攀搀 琀栀爀漀甀最栀 琀栀攀 挀攀渀琀爀攀 漀昀 琀栀攀 愀渀琀攀渀渀愀⸀ 吀栀攀 昀椀爀猀琀 漀戀猀攀爀瘀愀琀椀漀渀 䤀 挀漀甀氀搀 甀猀攀 琀漀 洀攀愀猀甀爀攀 琀栀攀 愀渀琀攀渀渀愀ᤀ 猀 戀攀愀洀眀椀搀琀栀 眀愀猀 搀漀渀攀 漀渀 䄀瀀爀椀氀 㔀Ⰰ 㤀㤀㠀 ⠀昀椀最甀爀攀 㔀⤀⸀ 吀栀攀 搀愀琀愀 搀椀猀瀀氀愀礀攀搀 愀 爀攀猀瀀漀渀猀攀 琀栀愀琀 氀愀猀琀攀搀 琀眀攀氀瘀攀 洀椀渀甀琀攀猀 昀爀漀洀 琀栀攀 昀椀爀猀琀 渀漀琀椀挀攀愀戀氀攀 椀渀挀爀攀愀猀攀Ⰰ 琀栀爀漀甀最栀 琀栀攀 瀀攀愀欀 猀椀最渀愀氀Ⰰ 琀漀 琀栀攀 戀愀猀攀氀椀渀攀 瘀漀氀琀愀最攀 漀渀挀攀 愀最愀椀渀⸀ 吀栀攀 琀椀洀攀 戀攀琀眀攀攀渀 琀栀攀 栀愀氀昀 瀀漀眀攀爀 瀀漀椀渀琀猀 眀愀猀 愀瀀瀀爀漀砀椀洀愀琀攀氀礀 㠀⸀㈀㔀 洀椀渀甀琀攀猀⸀㰀⼀瀀㸀 At the equinoxes the Sun passes through 15�� of arc each hour relative to the meridian of the observer. The amount decreases as a function of the cosine of the observer s declination. In other words, the arc traversed by the Sun decreases from its nominal value of 15�� per hour the further the Sun is from the celestial equator.
㰀瀀㸀伀渀 䄀瀀爀椀氀 㔀Ⰰ 琀栀攀 搀愀琀攀 漀昀 琀栀攀 漀戀猀攀爀瘀愀琀椀漀渀 椀渀 焀甀攀猀琀椀漀渀Ⰰ 琀栀攀 匀甀渀ᤀ 猀 搀攀挀氀椀渀愀琀椀漀渀 眀愀猀 愀瀀瀀爀漀砀椀洀愀琀攀氀礀 ⬀㘀ﴀ﷿ 吀栀攀 栀愀氀昀 瀀漀眀攀爀 瀀漀椀渀琀 椀渀琀攀爀瘀愀氀 眀愀猀 㠀⸀㈀㔀 洀椀渀甀琀攀猀⸀ 䄀琀 琀栀攀 挀攀氀攀猀琀椀愀氀 洀攀爀椀搀椀愀渀Ⰰ 琀栀攀 匀甀渀 琀爀愀瘀攀爀猀攀猀 ﴀ﷿椀渀 㐀⸀ 洀椀渀甀琀攀猀Ⰰ 戀甀琀 愀琀 ⬀㘀ﴀ﷿搀攀挀氀椀渀愀琀椀漀渀 椀琀 琀愀欀攀猀 㐀⸀ ㈀ 洀椀渀甀琀攀猀⸀ 吀栀攀 挀愀氀挀甀氀愀琀攀搀 戀攀愀洀眀椀搀琀栀 漀昀 琀栀攀 漀戀猀攀爀瘀愀琀椀漀渀 椀猀 琀栀攀爀攀昀漀爀攀 㠀⸀㈀㔀⼀㐀⸀ ㈀ ﴀ﷿僿 ﴀ﷿⳿ 漀爀 ⸀㤀ﴀ﷿ 吀栀攀 愀渀琀攀渀渀愀 戀攀愀洀眀椀搀琀栀 椀猀 琀栀攀爀攀昀漀爀攀 挀氀漀猀攀 琀漀 琀栀攀 瀀爀攀搀椀挀琀攀搀 ㈀ﴀ﷿ 䄀渀漀琀栀攀爀 漀戀猀攀爀瘀愀琀椀漀渀 漀渀 䴀愀礀 ㈀㤀 眀椀琀栀 琀栀攀 匀甀渀 愀琀 愀瀀瀀爀漀砀椀洀愀琀攀氀礀 ⬀㈀㈀ﴀ﷿搀攀挀氀椀渀愀琀椀漀渀 爀攀猀甀氀琀攀搀 椀渀 愀 挀愀氀挀甀氀愀琀攀搀 戀攀愀洀眀椀搀琀栀 漀昀 ㈀ﴀ﷿ 䘀甀爀琀栀攀爀 漀戀猀攀爀瘀愀琀椀漀渀猀 瀀爀漀搀甀挀攀搀 瘀愀氀甀攀猀 琀栀愀琀 搀椀昀昀攀爀攀搀 戀礀 渀漀 洀漀爀攀 琀栀愀渀 愀戀漀甀琀 㔀─ 昀爀漀洀 琀栀攀 攀砀瀀攀挀琀攀搀 戀攀愀洀眀椀搀琀栀⸀㰀⼀瀀㸀The Moon
㰀瀀㸀圀椀琀栀 猀甀挀挀攀猀猀昀甀氀 猀漀氀愀爀 漀戀猀攀爀瘀愀琀椀漀渀猀 甀渀搀攀爀 洀礀 戀攀氀琀Ⰰ 䤀 搀攀挀椀搀攀搀 琀漀 琀爀礀 氀漀漀欀椀渀最 愀琀 琀栀攀 䴀漀漀渀 愀渀搀 漀琀栀攀爀 愀猀琀爀漀渀漀洀椀挀愀氀 猀漀甀爀挀攀猀 琀漀 猀攀攀 眀栀愀琀 䤀 挀漀甀氀搀 搀攀琀攀挀琀⸀ 吀栀攀 䴀漀漀渀 攀洀椀琀猀 洀椀挀爀漀眀愀瘀攀猀 漀爀椀最椀渀愀琀椀渀最 昀爀漀洀 椀琀猀 琀攀洀瀀攀爀愀琀甀爀攀⸀ 吀栀攀 渀攀愀爀氀礀 䘀甀氀氀 䴀漀漀渀Ⰰ 愀猀 漀戀猀攀爀瘀攀搀 䄀瀀爀椀氀 Ⰰ 㤀㤀㠀Ⰰ 瀀爀漀搀甀挀攀搀 愀 猀椀最渀愀氀 爀攀猀瀀漀渀猀攀 漀昀 ㌀ 洀嘀Ⰰ 漀渀攀 琀攀渀琀栀 琀栀攀 猀琀爀攀渀最琀栀 漀昀 琀栀攀 猀漀氀愀爀 爀攀猀瀀漀渀猀攀⸀㰀⼀瀀㸀
㰀栀㌀㸀伀琀栀攀爀 伀戀樀攀挀琀猀㼀㰀⼀栀㌀㸀 The dramatic reduction in signal strength between the Sun and Moon made me wonder if I would be able to see more distant objects. Attempts to see sources known to be strong radio emitters, such as Cygnus A and Taurus A, were not successful. Reference charts showing the strength of signals from such sources compared to the signal strength of the Sun at 12 GHz, clearly showed that I was dealing with emissions so weak that I would probably not be able to distinguish them from the background noise created within the receiver system itself.
㰀瀀㸀䄀昀琀攀爀 昀椀瘀攀 洀漀渀琀栀猀 漀昀 爀攀猀攀愀爀挀栀Ⰰ 挀漀渀猀琀爀甀挀琀椀漀渀Ⰰ 攀砀瀀攀爀椀洀攀渀琀愀琀椀漀渀Ⰰ 愀渀搀 猀甀挀挀攀猀猀昀甀氀 漀戀猀攀爀瘀愀琀椀漀渀Ⰰ 䤀 挀愀洀攀 琀漀 琀栀攀 氀椀洀椀琀猀 漀昀 眀栀愀琀 洀礀 ⸀㈀ⴀ洀 猀愀琀攀氀氀椀琀攀 吀嘀 猀礀猀琀攀洀 挀愀渀 漀戀猀攀爀瘀攀⸀ 䤀渀 琀栀攀 攀渀搀Ⰰ 琀栀攀 猀礀猀琀攀洀 眀愀猀 渀漀琀 瘀攀爀礀 攀砀瀀攀渀猀椀瘀攀 愀琀 ␀㈀ 昀漀爀 琀栀攀 甀猀攀搀 搀椀猀栀Ⰰ 䰀一䈀Ⰰ 洀漀甀渀琀Ⰰ 琀爀愀渀猀洀椀猀猀椀漀渀 氀椀渀攀Ⰰ 愀渀搀 爀攀挀攀椀瘀攀爀⸀ 䤀 愀氀猀漀 瀀甀爀挀栀愀猀攀搀 愀 刀愀搀椀漀 匀栀愀挀欀 刀匀 ㈀㈀ጀ 㘀㠀䄀 搀椀最椀琀愀氀 瘀漀氀琀洀攀琀攀爀 眀椀琀栀 挀漀洀瀀甀琀攀爀 猀攀爀椀愀氀 椀渀琀攀爀昀愀挀攀 猀漀昀琀眀愀爀攀 椀渀挀氀甀搀攀搀 昀漀爀 氀漀最最椀渀最 搀愀琀愀Ⰰ 眀栀椀挀栀 挀漀猀琀 ␀㤀 ᐀ 戀甀琀 眀栀椀挀栀 栀愀猀 戀攀攀渀 漀渀 猀愀氀攀 昀漀爀 愀戀漀甀琀 ␀㌀ 漀昀昀 猀椀渀挀攀 䤀 瀀甀爀挀栀愀猀攀搀 椀琀Ⰰ 漀昀 挀漀甀爀猀攀⸀㰀⼀瀀㸀For anyone wanting to try radio astronomy, I have learned a couple of things that may be helpful. Be certain that your references are current.
㰀瀀㸀䔀愀爀氀椀攀爀 戀漀漀欀猀 漀爀 愀爀琀椀挀氀攀猀 洀愀礀 瀀爀漀瘀椀搀攀 栀攀氀瀀昀甀氀 最攀渀攀爀愀氀 椀渀昀漀爀洀愀琀椀漀渀 愀戀漀甀琀 琀栀攀 昀漀甀渀搀愀琀椀漀渀猀 漀昀 爀愀搀椀漀 愀猀琀爀漀渀漀洀礀 琀栀愀琀 栀愀瘀攀 渀漀琀 挀栀愀渀最攀搀 洀甀挀栀 漀瘀攀爀 琀椀洀攀⸀ 䈀甀琀 琀攀挀栀渀漀氀漀最椀挀愀氀 挀栀愀渀最攀猀 栀愀瘀攀 洀愀搀攀 琀栀椀渀最猀 瀀漀猀猀椀戀氀攀 椀渀 琀栀攀 氀愀琀攀 渀椀渀攀琀椀攀猀 琀栀愀琀 眀攀爀攀 渀漀琀 瀀漀猀猀椀戀氀攀 椀渀 琀栀攀 猀攀瘀攀渀琀椀攀猀 漀爀 攀瘀攀渀 洀椀搀ⴀ攀椀最栀琀椀攀猀⸀ 䘀漀爀 攀砀愀洀瀀氀攀Ⰰ 漀渀攀 戀漀漀欀 眀爀椀琀琀攀渀 椀渀 琀栀攀 洀椀搀ⴀ猀攀瘀攀渀琀椀攀猀 戀攀昀漀爀攀 琀栀攀 愀搀瘀攀渀琀 漀昀 猀愀琀攀氀氀椀琀攀 琀攀氀攀瘀椀猀椀漀渀Ⰰ 爀攀昀攀爀猀 琀漀 琀栀攀 椀洀瀀爀愀挀琀椀挀愀氀椀琀礀 漀昀 甀猀椀渀最 瀀愀爀愀戀漀氀椀挀 搀椀猀栀 愀渀琀攀渀渀愀猀 昀漀爀 漀戀猀攀爀瘀椀渀最⸀ 吀栀攀礀 愀爀攀 渀漀眀 焀甀椀琀攀 挀漀洀洀漀渀 椀渀 愀洀愀琀攀甀爀 爀愀搀椀漀 愀猀琀爀漀渀漀洀礀⸀ 匀琀爀椀瀀 挀栀愀爀琀 爀攀挀漀爀搀攀爀猀 愀爀攀 愀渀漀琀栀攀爀 攀砀愀洀瀀氀攀⸀ 吀栀攀礀 甀猀攀搀 琀漀 戀攀 愀戀漀甀琀 琀栀攀 漀渀氀礀 漀瀀琀椀漀渀 昀漀爀 挀愀瀀琀甀爀椀渀最 搀愀琀愀Ⰰ 愀猀椀搀攀 昀爀漀洀 琀愀欀椀渀最 瀀攀爀椀漀搀椀挀 瘀椀猀甀愀氀 爀攀愀搀椀渀最猀 昀爀漀洀 琀栀攀 瘀漀氀琀洀攀琀攀爀⸀ 一漀眀 搀椀最椀琀愀氀 琀攀挀栀渀漀氀漀最礀Ⰰ 猀甀挀栀 愀猀 䤀 甀猀攀搀Ⰰ 瀀攀爀洀椀琀猀 搀愀琀愀 琀漀 戀攀 爀攀挀漀爀搀攀搀 椀渀 攀氀攀挀琀爀漀渀椀挀 昀椀氀攀猀 琀栀愀琀 挀愀渀 氀愀琀攀爀 戀攀 愀渀愀氀礀稀攀搀 甀猀椀渀最 搀愀琀愀 瀀爀漀挀攀猀猀椀渀最 琀攀挀栀渀椀焀甀攀猀⸀㰀⼀瀀㸀Finally, networking is a useful way of gaining experience without having to go through a frustrating amount of trial and error in the early stages. Nevertheless, I found it worthwhile trying one thing and another even though it netted no results. It gave me time to process information gained by reading and talking with others interested in radio astronomy. Getting to know the quirks of my particular receiver and dish through trial and error helped me to understand how my equipment worked. Even with help from others, there is no doubt that the simple radio telescope project like the one described here takes a fair bit of patience. But I found it fun and worthwhile.
㰀栀㌀㸀刀攀昀攀爀攀渀挀攀猀㰀⼀栀㌀㸀Heiserman, D. L. 1975, Radio Astronomy for the Amateur (Tab Books: Blue Ridge Summit, Pennsylvania)
㰀瀀㸀䰀漀渀挀Ⰰ 圀⸀ 㤀㤀㘀Ⰰ 刀愀搀椀漀 䄀猀琀爀漀渀漀洀礀 倀爀漀樀攀挀琀猀 ⠀刀愀搀椀漀 匀欀礀 倀甀戀氀椀猀栀椀渀最㨀 䰀漀甀椀猀瘀椀氀氀攀Ⰰ 䬀攀渀琀甀挀欀礀⤀㰀⼀瀀㸀 㰀搀椀瘀 椀搀㴀∀昀漀漀琀攀爀∀㸀 Copyright © 2007 Edmonton Centre - RASC. Original design by kty of studio-plume.org for OSWD.