Posts by DC7KG

Es gibt eine neue Beta Version der SDR Console, Ver. 3.3

Detlev

Hi,

the output power of my VNA (SAA-2N) is 0.02 mW. Your amplifier has 13 dB gain, the result is an output power of 0.4 mW. That is not enough.

Best regards,

Detlev

Hallo Uli,

ich habe mit Pluto Vers. 0.37 und SDR Console 3.2 gemessen, USB mit 700 Hz moduliert. Die Nebenwellen im großen Abstand sind weg, dafür im geringeren Abstand einige.

Hallo Uli,

die 20 W Endstufe von PE1CMO braucht 70 ...80mW Eingangsleistung, der CN0417 macht 20 dB Verstärkung, so dass Du am Ausgang des Pluto nur etwa 1 mW benötigst. Ich werde das Spektrum mit Dreitonaussteuerung morgen mal messen.

Bei dem Signal/Rauschabstand des QO100 verschwinden alle Nebenaussendungen im Rauschen.

Gruß Detlev

Hallo Uli,

wie sieht denn Deine Station aus? Was kommt sendeseitig hinter dem Pluto?

Gruß Detlev

Here is the diagram of Rev. D

Quote from i2NDT

hi DC7KG !

can you send me the link to the manual of the Hugen79 interface?

did you try it?

73

de

i2NDT Claudio

Display More

Hi Claudio,

I attach the manual. I had some problems with the Hugen interface, probably caused by the USB driver

Best regards,

Detlev

Yes, the KE5FX tool is very helpful.

Regards,

Detlev

The MAV11 has a high Noise Figure.

Regards, Detlev

Hi George,

did you measure the phase noise?

Best regards,

Detlev

Hi Roberto,

Please send a sketch of your setup.

Best regards,

Detlev

The Pluto can uses clock frequencies up to 320 MHz, you have to choose the right scaling factor to get near to 80 MHz, i.e 320 x 1/4. Pluto uses 40 x 2 = 80 and when you use 50 MHz, then you have to change the factor to 1. 50 x 1 = 50.

Hi,

the Pluto uses 40 MHz x 2 = 80 MHz, you have to change the factor from 2 to 1, when you use 50 MHz.

Detlev

Hi George,

you need a much higher time constant for the VCO:

Configuration for VCO range, time constant (4-32000s) and a lot of other parameter

Regards,

Detlev

Hi,

the control loop is much too fast.

GPSDO producer say they reach the highest accuracy after 1 day of reception:

- High frequency accuracy (when tracked GNSS over 1 day)

<5e-11 at 1s

<2e-11 at 10s

<1e-11 at 100s

<5e-12 at 1,000s

<2e-12 at 10,000s

Detlev

Hi George,

very interesting. Rohde & Schwarz says:

This figure shows the proven MER measurement for a DVB-T signal that was mainly affected by unwanted modulator phase noise. The cause cannot be seen in the constellation diagram. The R&S®ETL can make the cause visible with a new unique measurement capability.

Best regards Detlev

Hi George,

did you measure the phase noise? There is a toolkit by KE5FX: http://www.ke5fx.com/gpib/readme.htm

Regards Detlev

Hallo Nick,

hier ist der Link zum UG570: https://ez.analog.com/cfs-file…nual_5F00_UG_2D00_570.pdf

Gruß Detlev

Hallo Nick,

der Hersteller gibt dazu im Reference Manual UG570 folgendes an:

REFERENCE CLOCK SETUP AND OPERATION

If the DCXO is not used, an external reference clock needs to be ac-coupled to XTALN (Pin M12). XTALP (Pin M11) is not connected (leave floating). The clock frequency must be between 5 MHz and 320 MHz, and can be scaled by 1×, ½×, ¼× and 2× using BBPLL, Rx and Tx reference dividers. The valid frequency range for the RFPLL phase detectors is 10 MHz to 80 MHz, and the scaled frequency of the reference clock must be within this range. For optimum phase noise it is recommended to operate the scaled clock as close to 80 MHz as possible. The selection between DCXO and external reference clock is made in the ad9361_init function.

The level for the clock should be 1.3 V p-p maximum(lower swings can be used but will limit performance). This signal can be a clipped sine wave or a CMOS signal. The best performance will be seen with the highest slew rate possible.

The XTALN (Pin M12) has an input resistance of ~ 10 kΩ in parallel with 10 pF.

PHASE NOISE SPECIFICATION

The AD9361 Rx and Tx RFPLLs use the DCXO or external clock as their reference clock as well. For this reason, it is extremely critical that the crystal or clock source have very low phase noise. The recommended phase noise specification is shown in Figure 2.

Das Bild habe ich ja oben eingestellt.

Gruß Detlev

Hi Nick,

für den AD9364 habe ich folgendes gefunden:

Gruß Detlev