Hi
I successfully now have a GPS locked 27MHz from a AD9850.Does anyone know the optimum injection level at the LNB,??
I'm using an Octagon dual LNB..
Next step to order a few 27MHz crystals and make a ladder filter and then a bit of gain .
the TCXO I fitted has a min level of 0.8V pk-pk, which seems to work OK, but that is min level and the typical level is not quoted in the spec.
Thanks
Richard g8jvm
optimum external LO level on LNB
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This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.
Thank you
Re: optimum external LO level on LNB
Richard,
For my Octagon LNBs, I found that an external injection level of -16dBm worked.
In general, use as little as possible but bear in mind that at other temperatures it may lose lock if the level is insufficient. I found that too high a level led to degradation in the LNB output spectrum.
Hope this helps.
73
Jen
For my Octagon LNBs, I found that an external injection level of -16dBm worked.
In general, use as little as possible but bear in mind that at other temperatures it may lose lock if the level is insufficient. I found that too high a level led to degradation in the LNB output spectrum.
Hope this helps.
73
Jen
-
Richard-g8jvm
- Posts: 29
- Joined: Thu Jan 19, 2012 12:04 pm
Re: optimum external LO level on LNB
Many thanks Jen,
thats exactly the info that was required,.The last thing I want are large signals around, its bad enough here that rotating the antennas around the noise floor is up and down like a yo yo
73 Richard
thats exactly the info that was required,.The last thing I want are large signals around, its bad enough here that rotating the antennas around the noise floor is up and down like a yo yo
73 Richard