It's all about the Software

Hi Simon,
after our messages on twitter, here I am to better describe converter definition needed for the C-band LNBs.
Currently UP or DOWN converters definitions are working subtracting or adding the local oscillator value (OFFSET) from the frequency: (FREQUENCY - OFFSET)
For C-BAND LNBs converter definition calculation should be:
OFFSET - FREQUENCY
an example:
Desired frequency 3623 MHz (to shown on software)
LNB offset 5150 MHZ (settable offset)
calculation: 5150-3623=1527 MHz (1527 SDR Frequency)

TNX in advance

Ah,

Now I understand.

Tnx Simon,
of course I'm available for any info and test

Hi Simon,
I think that a custom converter definition that can be configured in this way can satisfy all requests.
In attach also a classic C-BAND LNB spec.
73 Rocco IK8XLD

ik8xld wrote: Mon Apr 25, 2022 8:38 am Hi Simon,
I think that a custom converter definition that can be configured in this way can satisfy all requests.
In attach also a classic C-BAND LNB spec.
73 Rocco IK8XLD

Rocco

A question to you in my ignorance:

What is the reason for running the LO in the LNB at 5150 and not 2450?

73

Max

Hi Max,
I do not imagine the reason but they are all like this.
Have the oscillator at 5150 MHz.

73 Rocco Labella IK8XLD

OK Rocco thank you. Seems odd as one might imagine the frequency stability is harder at the higher frequency!

73

Max

A possible explanation could be that a 2450 MHz OL would be too close to the IF. (950 - 1750 MHZ)

73 Rocco Labella IK8XLD