Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)

In message , Gareth's Downstairs Computer
writes
Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)



We discussed this last year. I had some limited success using
Spectrumlab software but hit problems with tuning latency.

SM0VPO has a circuit for a hardware version here.

Http://www.sm0vpo.com/ under Morse Code, Stereo CW


Brian
--
Brian Howie

On 26/07/2017 13:09, Brian Howie wrote:
In message , Gareth's Downstairs Computer
writes
Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)



We discussed this last year. I had some limited success using
Spectrumlab software but hit problems with tuning latency.

SM0VPO has a circuit for a hardware version here.

Http://www.sm0vpo.com/ under Morse Code, Stereo CW


Brian


Actually Projects / Morse Code / Stereo CW, but thanks anyway.

The days of ex-GPO 88mH inductors seem to be long past.

Brian Howie wrote on 7/26/2017 8:09 AM:
In message , Gareth's Downstairs Computer
writes
Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)



We discussed this last year. I had some limited success using Spectrumlab
software but hit problems with tuning latency.

SM0VPO has a circuit for a hardware version here.

Http://www.sm0vpo.com/ under Morse Code, Stereo CW

That's what happens when you try to use a PC to do an MCU's job! Dedicated
hardware is pretty mundane. This should be a pretty simple task on fairly
minimal hardware. Filtering software is not too complex. A single FIR
filter can be used to generate one channel, say the low pass, then the high
pass can be found by subtracting that from the original signal.

This could be extended to work with a surround sound speaker arrangement and
achieve 360 degree separation of signals. Audio processing on MCUs is not
at all over taxing these days. A Raspberry Pi would be a great platform to
at least test out the concept and allow 100% COTS hardware.

--

Rick C

On 26/07/17 13:09, Brian Howie wrote:
In message , Gareth's Downstairs Computer
writes
Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)



We discussed this last year. I had some limited success using
Spectrumlab software but hit problems with tuning latency.

SM0VPO has a circuit for a hardware version here.

Http://www.sm0vpo.com/ under Morse Code, Stereo CW


Brian

Wouldn't a simple, switched capacitor filter, do the job- with much less
fuss?

On Wed, 26 Jul 2017, Gareth's Downstairs Computer wrote:

Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)


There was a guy with a last name of Hildreth who wrote a number of
articles on this sort of thing in Ham Radio magazine in the seventies.
Used active filters, but he also did some other things.

Receivers with phasing adapters could be modified so you could listen to
one sideband in one ear, and the other sideband in the other ear, that
apparently gave some interesting effects.

They guy who's written a lot in recent times in QST about the phasing
method, a string of projects, one was in effect a phasing receiver except
no audio phasing network. So he had two mixers, fed from an oscillator
with quadrature output, and then each of the mixers fed one of side of
stereo headphones. That apparently gave some nice depth effect.

Michael

On 26/07/2017 18:33, Michael Black wrote:
On Wed, 26 Jul 2017, Gareth's Downstairs Computer wrote:

Intrigued by the possibility of Binaural reception, where
audio filtering passes lo frequencies to the left ear
and higher ones to the right, causing the tuning of
a CW signal to move in front of your eyes, and musing
that headphones today are invariably stereo, and that
LM386 audio amps are as cheap as chips, that it should
be a feature of receivers to have two audio amps for the
stereo effect with the splitting filters before either of them,
and that those wishing speaker output might just as well
use the audio amps sold for computer use, and now that
the 100 miniature roller-operated microswitches have
arrived from China it is time to get on with the
"vapourware" 50 years RX project, if anything, just
to spite / spike one of M3OSN's guns?

(C) Copyright 2017 The Impossibly Long Sentence Co Ltd :-)


There was a guy with a last name of Hildreth who wrote a number of
articles on this sort of thing in Ham Radio magazine in the seventies.
Used active filters, but he also did some other things.

Receivers with phasing adapters could be modified so you could listen to
one sideband in one ear, and the other sideband in the other ear, that
apparently gave some interesting effects.

They guy who's written a lot in recent times in QST about the phasing
method, a string of projects, one was in effect a phasing receiver
except no audio phasing network. So he had two mixers, fed from an
oscillator with quadrature output, and then each of the mixers fed one
of side of stereo headphones. That apparently gave some nice depth effect.

Michael

Also discussed in Pat Hawkers Technical Topics column, long ago, whe I
was a G8..
Dave
G4UGM

On 26/07/2017 21:30, David Wade wrote:
On 26/07/2017 18:33, Michael Black wrote:
On Wed, 26 Jul 2017, Gareth's Downstairs Computer wrote:

Intrigued by the possibility of Binaural reception,
snip

There was a guy with a last name of Hildreth who wrote a number of
articles on this sort of thing in Ham Radio magazine in the seventies.
Used active filters, but he also did some other things.

Receivers with phasing adapters could be modified so you could listen
to one sideband in one ear, and the other sideband in the other ear,
that apparently gave some interesting effects.

They guy who's written a lot in recent times in QST about the phasing
method, a string of projects, one was in effect a phasing receiver
except no audio phasing network. So he had two mixers, fed from an
oscillator with quadrature output, and then each of the mixers fed one
of side of stereo headphones. That apparently gave some nice depth
effect.

Michael

Also discussed in Pat Hawkers Technical Topics column, long ago, whe I
was a G8..
Dave
G4UGM

Around 1979 IIRC. There was a simple circuit using passive components in
a highpass/lowpass config to drive a pair of headphones. It worked well
for me with CW.

--
Mouse.
Where Morse meets House.