Microwave link setup not reaching far!

[XXL]

Just got a new AGD horn for a micro link setup but it seems to be really down on power compared to other horns iv had in the past. I'm struggling to link around half a mile away. Anyone know why this might be ? Does the LNB make any difference ? I know you can buy high gain ones but is it just marketing ?

Its a single LNB and my horn voltage is at 6v. Iv previously ran them at 7.2 or 8v but for some reason on this horn the bass disappears more and more the higher the voltage.

Also the LNB cable has been beeped out with multimeter. No shorts.

[mpx]

Are there two diodes in the cavity? If so, you can remove the one at the front of the horn, its for receive and much larger than the rear diode, about half a centimetre thick. If you're not sure, post a photo.

Also you'll want to have a resistor and capacitor in series across the diode for stability. There is a diagram or picture around the forum somewhere, from memory its a 103 cap and a 100 ohm resistor.

Its possible you have a lower power diode. The small AGD ones aren't as good as its bigger brother. Is the link stronger with the voltage at 7.2V ?

What size waveguide do you have on it?

[XXL]

By diodes, do you mean the metal plates between the gunn and the horn ? iv removed both of them.

And i have the largest flange/horn you can get on AGD horns with the small allen key tune screw.

If i run the gunn on 7.2v i loose alot of bass. the best is at 5.5v. I cant tell if its any stronger the higher the voltage.

[mpx]

I believe the metal plates should stay in place but it depends on the horn design.

The diode to remove looks a bit like a mains fuse you get in a wall plug.

A decent horn and an LNB can link over several miles but depends on how good the kit is at both ends. If possible, use a satellite dish for the receive end. You can also use a dish for the transmit end, getting the focal point right is a bit fiddly but worth it if you have the patience.

[XXL]

Should I just cut the “fuse” looking thing out at the front then ? And yeh Iv linked for miles before.

Also on the rx side is a small sharp type cann.

[mpx]

It is removable by unscrewing a threaded cap on the top of the casing. Be sure its a receive diode, are there two diodes in there? Big one to the front, small one at the back?

Sharp cans are fine.

Is the white noise clean?

[XXL]

Yeh clean white noise. And iv never had to remove the front diode before. Is it possible iv got a lower power diode ?

[mpx]

If you've bought them from a builder chances are they removed the diode and put the components on the outside already.

Some diodes do run better at around 6V so it might just be that. I'd say put a dish on the receive end to pull the link in. A sky mini dish will do