Can anyone tell me what signal level to expect from the PSK beacon on QO100 via Pluto and SDRC?
At the moment mine seems quite low at -112dBm or S2 but listening via the batc Goonhilly sdr it is about s9+10db. I am using a 90cm dish and 0.1 lnb.
Thanks
QO100 beacon signal level
QO100 beacon signal level
David M0TGC
Re: QO100 beacon signal level
David,
Signal strength readings mean nothing.
Compare the Signal to Noise Ratio, then decide if anything is wrong.
73 Alan G4ZFQ
Signal strength readings mean nothing.
Compare the Signal to Noise Ratio, then decide if anything is wrong.
73 Alan G4ZFQ
Re: QO100 beacon signal level
Alan
Fair comment. The Goonhilly snr is about 18dB and my Pluto is about 10dB.
What do others get?
Fair comment. The Goonhilly snr is about 18dB and my Pluto is about 10dB.
What do others get?
David M0TGC
Re: QO100 beacon signal level
Hi
1 meter dish, lnb,Limesdr
abt 30-35 db 'eyeball' on the signal history display
SNR by Simon's compute: 30-40 db
de Joe 4X1RV.
1 meter dish, lnb,Limesdr
abt 30-35 db 'eyeball' on the signal history display
SNR by Simon's compute: 30-40 db
de Joe 4X1RV.
Re: QO100 beacon signal level
I should have thought, even that is not so simple.
You have to know what bandwidth the SNR is being measured in to be able to compare.
An interesting point. I've no figure for when I tried, must get it going again.
The SNR however you measure it should be set by the time the signal leaves the LNB. Dish size/aim/efficiency/LNB noise. Anything following it must not increase the noise level. I'd expect every receiver to be much the same on any one system.
As David says "What do others get?" Maybe better answered in a dedicated QO100 group?
73 Alan
You have to know what bandwidth the SNR is being measured in to be able to compare.
An interesting point. I've no figure for when I tried, must get it going again.
The SNR however you measure it should be set by the time the signal leaves the LNB. Dish size/aim/efficiency/LNB noise. Anything following it must not increase the noise level. I'd expect every receiver to be much the same on any one system.
As David says "What do others get?" Maybe better answered in a dedicated QO100 group?
73 Alan
Re: QO100 beacon signal level
I re-aligned the dish and lnb and tried other lnb's and now have a snr of 20-23dB. This is better than it was but I can't get any where near the 30dB others have mentioned.
Thanks to all.
Thanks to all.
David M0TGC
- Simon G4ELI
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Re: QO100 beacon signal level
I would like to see screenshots of SNRs of 30dB on the beacon - despite a 1.4m dish I can't achieve this.
Re: QO100 beacon signal level
Hi Simon.
Attached a screenshot shoing S/N of 38 (get 32-40 depending of the data on the beacon) .
Attached a screenshot shoing S/N of 38 (get 32-40 depending of the data on the beacon) .
Re: QO100 beacon signal level
Hi Simon,
1.8m offset dish with LNB "looking" through the feed helical antenna, getting an SNR of around 39dB for the CW beacon and around 28dB for the data beacon @ 1.2MHz bandwidth
Vy 73
Geri, DK8KW
1.8m offset dish with LNB "looking" through the feed helical antenna, getting an SNR of around 39dB for the CW beacon and around 28dB for the data beacon @ 1.2MHz bandwidth
Vy 73
Geri, DK8KW
Last edited by DK8KW on Sat Jan 23, 2021 3:49 pm, edited 3 times in total.
Re: QO100 beacon signal level
Hi
To add: Just noise is S6 S5 on signal history
So levels are similar to the display of the Goonhilly site...
To add: Just noise is S6 S5 on signal history
So levels are similar to the display of the Goonhilly site...