Showing posts with label simple sideband. Show all posts
Showing posts with label simple sideband. Show all posts

28 Aug 2017

10m Simple Sideband

Yes, you read correctly - simple sideband, not single sideband.

For some time, I have had in my mind a very simple 10m rig. Sadly, my stroke got in the way, so this has not progressed. Such a rig would be ideal for Es and, certainly here in the UK, most of Europe should be workable with a simple antenna. At some point, I'd like to complete this. Maybe someone else already has.

A few years ago, the whole world would have been workable. Sadly with declining conditions, this is far less likely now on 10m. May, June and July are the best months for Es (sporadic-E) in the northern hemisphere. Of course, there is nothing stopping you work local SSB stations at any time.

See https://sites.google.com/site/g3xbmqrp3/hf/10msimple_sb .

14 Jun 2013

Low costs SSB "Pixie" from Argentina

Pedro LU7HZ has sent me an update on work in Argentina on a low cost approach to an HF QRP SSB transceiver using very few parts. Basically they are using simple electronics coupled with an SDR approach to the modulation and demodulation process.  My own approach would be the fully low tech approach (for a CW/DSB rig) but Pedro's approach is innovative and worth watching. I hope he produces kits or, at the least, documentation to allow others to duplicate the idea as it comes to fruition.
Roger,

This is a project we've been working together with Willoh (LW3DYL) which fits partially into your quest for an extremely low cost and easy to build rig ("UKP 20 decent HF...") although not using the low tech approach but the other way around.

The design is still being debugged and more simplifications will be attempted (such as a more simpler TR/RX switch and eliminate the 7474 based quadrature filter replacing it by an RC approach. The net result should be a one IC and 4 transistors design plus PA final.

The design uses an USB power source (out of an inexpensive cell phone switching power supply or straight out of the USB port at the PC) having 0.5W with it; more like 1W with +12V.

Main software platform will be a modified version of KGKSDR. Main use should be CW or SSB although no reason why not to use it with PSK or FreeDV or WSPR.

Should fit on a (small) pocket.


Main limitation so far is available time from the builders to devote to the project.

73 de Pedro LU7HZ
Dr. Pedro E. Colla
Va.Belgrano-Ciudad de Cordoba
Cordoba- Argentina
"La vida no es esperar a que pase la tormenta, es aprender a bailar bajo la lluvia". Anonimo

21 Sept 2012

10m Simple Sideband (DSB) Transceiver

Regular readers of this blog will recall that about a year ago I started breadboarding a simple DSB speech transceiver for 10m. Having had great success with the WISPY 10m WSPR transceiver, I now have a very simple design for the TX part of such a DSB speech transceiver (just need to add an audio preamp/clipper/filter), so I am beginning to get ideas together for this project again. A power of around 1W pep (DSB) equivalent to 500mW pep SSB is the minimum I think. On RX a single balanced diode mixer (or a double balanced mixer such as an ADE-1 or SBL1) should be fine. For the VFO, I am thinking of a mixer/VFO with a tuning range of 28.4-28.6MHz. The RX audio design from WISPY works well but it will need another audio stage to drive headphones.

I want to have another go at a 136kHz transverter (based on my latest architecture), more non-line-of-sight (NLOS) optical comms, E-field probes, more earth mode comms, WSPR beacons for other bands,  etc etc...

My problem is I've too many ideas in my head and not enough hours in the day to try them all out. What I need is a spare, free, design team (!) to take these ideas forward whilst I get on with other things, like looking after the grandchildren, gardening, maintaining the house, eating and sleeping etc. Since retiring 4 years ago I have no idea why I've no spare time!