Output Attenuator

[F1SSF]

Hi alls,
I have a doubt about software, to use it for power ajustement because it is written in the wiki:
Note that it should only be put in-circuit for use with the signal generator at present. a further software update is required before it can be used with the Portsdown DATV transmitter.
Please can you confirm?
Also what is the best attenuator actully fully supported? (PE43713?)
Regards.
Franck F1SSF

[G8GKQ]

Hi Franck

Sorry, the wiki had not been updated. The attenuator can be used with the transmitter. Now updated.

The PE43703 or PE43713 work well.

Dave

[F1SSF]

Hi Dave, don't be sorry.
Ok for infos, but confirm PE43703 et PE43713 are same, because in RpdiDTVA screen, there has not button flaged PE43703 .
Best 73
Franck

[G8GKQ]

Hi Franck

Yes, as far as I can tell, the PE43703 and PE43713 are the same.

Dave

[F1SSF]

Hi Dave,
Sometimes, when I change the attenuation, I have a random state of the output.
If I want to be sure, I must reboot the RPI, and there it is perfect.
Have you noticed this phenomenon?
Best 73 Franck F1SSF

[G8GKQ]

Hi Franck

I had similar problems early on in my construction caused by very high speed reflections or ringing on the spi lines. I cured it by putting 200 ohm series resistors in the 3 spi control lines to the attenuator.

I have just checked my attenuator with the latest software and cannot reproduce any problems.

Dave

[F1SSF]

It is random, and I see this since the last version, but I not sure.

cured it by putting 200 ohm series resistors in the 3 spi control lines to the attenuator.

I have put 1K resistor like Wiki. Also I can try change 1K with 220U, and I can add smd emi filter on spi lines.
I can test this weekend.
Thank you Dave.