"The Water Hole"
Have you noticed that this prototype feedhorn is two coffee cans silver-soldered together? When all fine-tuning adjustments are completed, the "Maxwell House cylinder" will be replaced with a genuine brass assembly.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| The Feedhorn | |||||||||||||||||||||
| 1420 MHz is The Hydrogen Line "The Water Hole" |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||
| This is a water hole feedhorn: 6 inches diameter by 10.5 inches long. Note the right angle connector which connects the probe to the LNA (Low Noise Amplifier). The preamp is "floating' in a polished aluminum case which shields it from direct sun light, yet allows free air movement. Rain and weather exposure is not a consideration since everything electronic is sealed, but heat is always an enemy (cool FETs are a good thing). | |||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||
| Details of the LNA housing and the non-inductive right angle "F" connector. See the bright, polished aluminum box ... I like shine-eee things. | |||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||
| Here's a view of the aluminum struts which attach to the dish's arm-mounts. Note the three mounting brackets that hold the struts. They are slotted so that the feedhorn can be adjusted in its mounted position, relative to the dish focal point, after installation - for fine tuning of maximum gain and minimum (spill over) noise). Inside the bright sun-shield box is the LNA which has a gain of 18 dB at 20 volts and a bandwidth of 950 to 2050 Mhz. Have you noticed that this prototype feedhorn is two coffee cans silver-soldered together? When all fine-tuning adjustments are completed, the "Maxwell House cylinder" will be replaced with a genuine brass assembly. |
|||||||||||||||||||||
| home | Next | ||||||||||||||||||||
| Back | |||||||||||||||||||||