Carl Reade

Hi you will also need to know where and when the Milky way will pass through the horn. Stellarium software etc. Carl

Hi maybe a factor maybe not I had read that the PI itself like most computers can cause interference via RF and needs to be a good distance from the LNA and antenna. Maybe the bump issue especially if it's using WiFi as well.

Excellent post. That's how small it is. Software is half the battle. I am also not sure what the humps are Peter on your last post, that is an issue in the receive end.

Hi all yes I would recommend using the sdr Averager plugin to start with and take a calibration about an hour before the galaxy comes into view of the scope. Bear in mind the H line will usually only be 2db above the noise very weak. I would also ensure the dB increments on the left are as low as you can set, I think the most it goes down to is 3 dB. If aiming for the sun there will be no humps etc the entire noise level will rise. Software settings can be half the battle.

Hi yes it can be difficult to know if a H line dedicated LNA is working but you should see a rise in the noise level when switching on. A wideband LNA is much easier to test as you can just test it on any signal in SDRsharp to see if it's working. If your H line Freq is clear of spikes you should get away without a filter. I found it easier to use SDRsharp with the IF Averager plugin. It can be calibrated flat. As per one of your links. The hump can be easily seen when using it. Then go on to the more complex software.

Hi, if you have the software running, when you turn on the amp the noise level should jump up. Will give you an indication things are connected. The last thing you want to use in calibration is the ground. The noise from the ground is far higher than cold sky hence would wipe out any readings. Top tip we have a convenient large orange noisy ball in the sky 😁 your entire noise level should rise when pointed at it. If your system can't see the sun it's unlikely it will see the H line. Go for the sun first. Keep at it you will get there.

Hi here a link to a really useful site which helped me enormously. http://www.parac.eu/ Take a look in the project section especially project 3 and 9 in the list. Regards Carl

Excellent results! Keep posting👏

Yes there are three peaks in there here's what I got a while back. Working well!!

Another way would be to feed the system with a dummy load instead of the antenna for a period of time while recording. Straight into the LNA then reconnect the antenna feed. Carl

Hi good work! There is a plugin for SDR# called IF Averager which will bring out more detail. There is another which flattens out the spectrum but can't remember what it was. Carl

Can be a any type of metal, but needs to be weather resistant.

Have a look at this link from the PARAC site. http://parac.eu/projectmk3.htm

Hi probably around a minimum of 5 meters of distance from radio gear to PC. It would also be beneficial to have the receiver in a metal box. I have had the receiver beside the PC without any problems but depends on your rf environment. You won't know what interference, if any, until you look at the band. Regards Carl

Hi if you have a read through the thread most of what you are asking is in there.