Monday, January 09, 2012

More Operatics

Paul PC4T may be taking a rest from blogging but he is still active. Yesterday evening I spotted him using the new Opera mode.

Andy K3UK has prepared a quick guide to using Opera which some may find helpful. As he points out, Opera is not a QSO mode. The only information that is sent in a beacon transmission is your callsign. Other information that is displayed in the software such as QTH, distance and bearing is sent over the internet back-channel by connected software clients.

Eldon WA0UWH has taken the Parallax Propeller code from my previous post and tried it out on the air. He has already received several reception reports.

Before I can do the same I will need to build a small PA / LPF with an output in the range 200mW to 500mW. Hopefully I can find a suitable circuit that uses standard components such as 2N3904 or 2N2222 which I have in my parts box. Suggestions welcome.

10 comments:

Paul PC4T said...

Hi Julian, yes I am still active on air. I like Opera and I will test it on 30 m daytime and maybe tonight on 160 meter. See if it can beat WSPR.

mat fauzi said...

I am new in ham radio.I always enjoy reading of your projects and reviews.

73
9w2CFZ West Malaysia

PE4BAS, Bas said...

What is your opinion Julian, do you think this mode can beat WSPR? I'm a little suspicious as it is made by the same guy that made ROS. Only tests will reveal! 73, Bas

Julian Moss said...

I haven't seen enough reports to form a conclusion, Bas, but my feeling is that Opera2 is at least as good. Theoretically it should have an edge over WSPR as it is a) slower, b) narrower and c) contains less information. It does however have an annoying propensity to report what are obviously decode errors.

Lynn (D) said...

I'll be downloading Opera shortly, but until I get it up and running, does it have a Receive-Only mode and what frequency is being used on 30m?

Julian Moss said...

Yes, beaconing can be turned off. 10.135 seems to be the 30m frequency.

Anonymous said...

Julian,

It is good to see you messing about with your Ham radio interests.

As to OPERA, it is always good to see new ideas and innovation and it seems that OPERA has caught the attention of many. Unfortunately there is no version of OPERA (yet) for LINUX nor does it seem to work with LINUX and WINE.

I have been trying to follow the many developments of this new mode as it does appear to have value. I am going to try and dig deeper into to the technical details of the mode and see if I can't get some sort of decoder working on LINUX. Perhaps a stand alone encoder/decoder based on one or another of the numerous Arduino (i.e Mega 2560) or ChipKIT (Arduino like PIC board) or RaspberryPI. Something like the RaspberryPI might hold a lot of promise.

cheers, Graham ve3gtc (Ottawa, Canada)

Richard said...

Hello Julian

For a very effective 500mW output linear, have a look at Harry Lythall's site - http://www.sm0vpo.com/

The linear uses 5 transistors (BC547/2N2222) and has 21dB gain.

Good Luck... and keep fighting!

73 de Richard F5VJD

Julian Moss said...

Thanks, Richard. That looks interesting, though the amp does not need to be linear for this application.

Richard said...

Hi again Julian

I realised that it doesn't have to be linear, but a linear broadband amp' is a very useful thing to have in the shack.

An alternative to Harry's design is the JBOT (Just a Bunch Of Transistors ) from Ashar Farwan ( of BITX20 fame) using 5 easily obtainable transisors producing 5W output for 1mW input.

... and the layout is not so cramped which is bound to be easier for you at the present.

73 de Richard F5VJD