- Joined
- Jan 1, 2000
- Messages
- 16,233
- Reaction score
- 4,202
- Points
- 113
- Age
- 81
- My Satellite Setup
-
Triple Dragon, Dreambox 8000, Echostar AD3000ip, TBS6522,6925,6983 PCie cards.
Gibertini 1.25m motorised dish driven by the AD3000, with either Inverto BU Quad or Norsat / XMW Ka LNBs . SMW 1.05m + 3 other dishes. Speccy: Promax HD Ranger+
- My Location
- The Flatlands of East Anglia
Another day, another Inverto...
I needed a spare feedhorn for my KA LNBs, and as the one removed from the Inverto KA LNBF I had outperforms the Norsat FD1000 on them, I aquired another one with the intention of depriving that of said feedhorn.
Before I do that, I thought I'd experiment with trying different DRO pucks in the LNB to see if it's capable of working to a different KA band. In a word, yes.
In my opinion (and it may be common knowlege, although I hadn't expected it to be so), the DRO in the Inverto uses a 10.6 GHz KU puck, and the Inverto operates using its second harmonic to oscillate at 21.2 GHz - I don't see any frequency doubler before the mixer in the circuit, but I stand to be corrected.
This was proven by removing the original puck and substituted it for a 10.6 GHz KU one, scavenged from an old KU LNB. The results were the same on KA-Sat 9a as with the original DRO puck.
Now for some fun. I then re-substituted the puck for a 9.75 GHz KU one, to see if the LNB would work in the KA C Band. I adjusted the DRO screw to bring the oscillator down to below the band, rather than the oscillator working above band, as with the normal Inverto's inverted spectrum output.
Now with the oscillator tuned to 19.035 GHz, I went to 12W to see if I could receive the carriers at 20307V and 20730V. No problem, good signals at 5.8dB and 9.1 dB. Allowing for the -3dB drop using a circular LNB, results seem promising.
There are some inclined sats in this band, as Vipersan and myself have received with the Hughes LNB, that could be worth investigating later.
A point worth making regarding changing DRO pucks - I found that rather than tediously glueing and unglueing them from the circuit board, I used Sellotape double-sided tape. Sticks firmly and is easily removed. Glueing the puck properly is an option if I decide to use this LNB purely for the KA C Band, but at present this is just for testing the capability of the LNB.
I needed a spare feedhorn for my KA LNBs, and as the one removed from the Inverto KA LNBF I had outperforms the Norsat FD1000 on them, I aquired another one with the intention of depriving that of said feedhorn.
Before I do that, I thought I'd experiment with trying different DRO pucks in the LNB to see if it's capable of working to a different KA band. In a word, yes.
In my opinion (and it may be common knowlege, although I hadn't expected it to be so), the DRO in the Inverto uses a 10.6 GHz KU puck, and the Inverto operates using its second harmonic to oscillate at 21.2 GHz - I don't see any frequency doubler before the mixer in the circuit, but I stand to be corrected.
This was proven by removing the original puck and substituted it for a 10.6 GHz KU one, scavenged from an old KU LNB. The results were the same on KA-Sat 9a as with the original DRO puck.
Now for some fun. I then re-substituted the puck for a 9.75 GHz KU one, to see if the LNB would work in the KA C Band. I adjusted the DRO screw to bring the oscillator down to below the band, rather than the oscillator working above band, as with the normal Inverto's inverted spectrum output.
Now with the oscillator tuned to 19.035 GHz, I went to 12W to see if I could receive the carriers at 20307V and 20730V. No problem, good signals at 5.8dB and 9.1 dB. Allowing for the -3dB drop using a circular LNB, results seem promising.
There are some inclined sats in this band, as Vipersan and myself have received with the Hughes LNB, that could be worth investigating later.
A point worth making regarding changing DRO pucks - I found that rather than tediously glueing and unglueing them from the circuit board, I used Sellotape double-sided tape. Sticks firmly and is easily removed. Glueing the puck properly is an option if I decide to use this LNB purely for the KA C Band, but at present this is just for testing the capability of the LNB.
