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RF / power specifications

Thomas Abbott 2021/06/22 22:18

I've just received a shiny new V4, amazing gadget at the price.

Does anyone know where I can find some RF specifications, particularly:

Typical output power, in each  ADF4350 setting.
One website says it's 0, -3, -6, -9 dB, the DMESG screen says 0, -6, -15, -27.
Datasheet says -4 to +5 dBm, programmable in 3 dB steps, so that makes sense.
I don't mind that it's not flat but some approximate values would be useful to know when driving an amplifier.
I found some figures in post #1867 from mce66, are these applicable to the V2.4?

Maximum input power for linear operation.
When measuring S21, how much power above a short cable can the receiver tolerate before it overloads the ADC
Can I measure a 20 dB amplifier barefoot, or must I attenuate down to the port 1 output level?

No-damage input power in dBm
Can port 2 tolerate 0 dBm input?  10 dBm?  I see an attenuator on port 2 in the schematic.

Thanks, Thomas

Siegfried Jackstien 2021/06/23 12:45

i measure amps with an att of roughly the same size

means i measure a 20 db mmic wit a 20 db att

or behind my 13cm amp i use 60 db (it has 50 to 55 db gain)

the 60 db is split in 20 + 40 and depending if i want to measure low
signal gain or higher signal gain i place 60 behind (high level) or 20
in front of the amp and 40 behind it (low level)

port 2 can sure tolerate 0dbm ... but not 30 dbm ;-) ... for saety you
should measure on the lower end

greetz sigi dg9bfc

Am 23.06.2021 um 07:18 schrieb Thomas Abbott:

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