Receive filters; switching

Eric W1NEJ

Can anyone explain the operation of the pass band receive filters in the AU520? Are the 7th order filters just for the contest bands, or are they now for all bands? Are these filters now magic, or do they still use inductors (coils) and capacitors?

Are these filters now electronically switched, and can a single antenna now be used for two or more slice receivers and run those through the appropriate filters, or will I still get the filter switched out (and "WIDE" displayed in the spectrum display)? I heard a rumor there was some sort of fast switching or multiplexing for that situation which implies electronic switching.

Mike-VA3MW

They are the same filters as the 8600, 7th order and for all bands.

You will still get WIDE if you try to use 2 different bands on the same Antenna port.

And, that is why they are called rumours. Someone is inventing technology that doesn't exist. They owe you a ****.

VE7ATJ_Don

So Mike… am I right in thinking that the Aurora is mainly the 8600 with a different/better transmitter and built in power supply? All the basic components (FPGAs, etc.) are essentially the same as in the 8600?

Eric W1NEJ

Thanks Mike. But the part about ALL filters (not just contest band) now being 7th order is true.

Regarding a single antenna feeding two filters: feeding a single antenna into two different filters, while maybe allowing for more flexibility, would have to be a compromise when it comes to noise. But it could be done, right?

Am looking forward to receiving the new AU520 I have ordered on Group 1!!

Mike-VA3MW

I am not an RF engineer so I really can't comment on what can or can't be done. In the absence of our filters (aka, in WIDE mode), you could always add your own RF bandpass filters.

Thanks for your support and we are still on track to start shipping in September baring any new hurdles. As a customer with a unit on order, you would have received 1 personalized update on the progress. That was a few weeks ago. We hope to get another out this week.

73

Trucker

I got the update email. Very encouraging. I guess my math is off slightly. I was under the impression that 1/4 of 12 months is 3 months. Everything I have been told says projected shipping should start in the 4th quarter of this year. That should put shipping to start as early as October. But, if it starts in September, I certainly won't complain! Looking forward to my AU-520M arriving!

James

WD5GWY

Eric W1NEJ

At 2:24 in this video, they say "the pre-selectors (band pass filters?) in the radio are now all solid state (electronically?) switched", so it would seem that that part of the "rumor" was also true.

Eric

https://www.youtube.com/watch?v=3p_HBOOqQmc&t=1156s