Hello Mike,

If you Google on "Synchronous AM Detector" and "Exalted Carrier Reception"
you'll find lots of info

This is good place to start....
http://www.radio-electronics.com/inf...t/sync_det.php


Regards ............ Zim

--
MikeK
"Graeme Zimmer" wrote in message
...
Hello Mike,

If you Google on "Synchronous AM Detector" and "Exalted Carrier Reception"
you'll find lots of info

This is good place to start....
http://www.radio-electronics.com/inf...t/sync_det.php


Regards ............ Zim
Thanks Graeme,
I'm thinking about building the mixer that was in QST Feb., 1993, an
article by
Jacob Makhinson. Titled, "A High-Dynamic-Range MF/HF Receiver Front End"
The mixer uses a quad FET IC, (Si8901 from Calolgic corp.)
The only online reference that I can find is here; See pdf pages 26 (text)
27 (schematic)
http://files.bluecrow.net/Amateur%20...ok_2007/11.pdf
The front end is designed in three modules, preamp, mixer, and post amp.
Anyway I'm thinking about building the mixer and playing with it in the
AMBCB.
Even thoughts about building an I/Q receiver.
Mike
(Note; I do more thinking than building ;-)

In article ,
amdx wrote:

Thanks Graeme,
I'm thinking about building the mixer that was in QST Feb., 1993, an
article by
Jacob Makhinson. Titled, "A High-Dynamic-Range MF/HF Receiver Front End"
The mixer uses a quad FET IC, (Si8901 from Calolgic corp.)
The only online reference that I can find is here; See pdf pages 26 (text)
27 (schematic)
http://files.bluecrow.net/Amateur%20...ok_2007/11.pdf

Google around for "H-mode mixer" and "Tayloe mixer" if you want more
information. http://www.webalice.it/romano.cartoc...mode_links.htm
will get you started with *many* links to investigate.

There has been a lot of interest in this sort of switching mixer
topology in recent years... quite a few articles in QEX for example.
Many designs have come out, some of which are based on general-
purpose multi-FET parts such as you suggest, and others which are
based on CMOS "fast bus switching" ICs, such as the FST3125 and
similar. This seems to be a very good topology for handing signals
having a very wide dynamic range... I believe that Elecraft uses a
design of this sort in their K3 transceiver.

The front end is designed in three modules, preamp, mixer, and post amp.
Anyway I'm thinking about building the mixer and playing with it in the
AMBCB.
Even thoughts about building an I/Q receiver.

Yeah, I've been toying with that sort of idea too... making a
"binaural" direct-conversion receiver. There was a binaural design
published in QST a year or so ago, which uses the NE602 or similar
Gilbert-cell mixers... building one which uses H-mode switching mixers
and a couple of low-noise audio amplifying chains could be fun.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In article ,
"amdx" wrote:

--
MikeK
"Graeme Zimmer" wrote in message
...
Hello Mike,

If you Google on "Synchronous AM Detector" and "Exalted Carrier Reception"
you'll find lots of info

This is good place to start....
http://www.radio-electronics.com/inf...t/sync_det.php


Regards ............ Zim
Thanks Graeme,
I'm thinking about building the mixer that was in QST Feb., 1993, an
article by
Jacob Makhinson. Titled, "A High-Dynamic-Range MF/HF Receiver Front End"
The mixer uses a quad FET IC, (Si8901 from Calolgic corp.)
The only online reference that I can find is here; See pdf pages 26 (text)
27 (schematic)
http://files.bluecrow.net/Amateur%20...ok_2007/11.pdf
The front end is designed in three modules, preamp, mixer, and post amp.
Anyway I'm thinking about building the mixer and playing with it in the
AMBCB.
Even thoughts about building an I/Q receiver.
Mike
(Note; I do more thinking than building ;-)

You should look at the Northern Radio Model N570/571 Marine SSB Radios,
that were designed and built back in the Early 70's. They used at rather
unique design with a Double Balanced Mixer at the Receive Antenna Port,
that moved the IF up to a low VHF biDirectional Amp and Filter, and then
back down to a 10.7 Mhz IF with another Double Balanced Mixer, and on to
the Crystal SSB Filter, and Demodulator. The Double Balanced Mixers were
driven by an LO System that canceled out any Frequency Drift, by using
opposite Mixing Images.

Hi again Mike,

I'm thinking about building the mixer that was in QST Feb., 1993

You might have a look at my old DSP receiver at:
http://members.wideband.net.au/gzimmer/


Regards ............. Zim

Graeme Zimmer wrote:

You might have a look at my old DSP receiver at:
http://members.wideband.net.au/gzimmer/

I have built several Softrock kits and have no inclination to use any
other receiver as a result. It's a receiver from heaven.

Looking at yours and the simple block diagram I am curious about how
this differs from quadrature processing.

Can you provide a few words of explanation.

Jack K9act

Hi Jack,

Looking at yours and the simple block diagram I am curious about how this
differs from quadrature processing.

I'm not sure I understand your question.

As the diagrams show, the VFO is divided by four to produce 90deg quadrature
LO signals which drive two mixers.The two audio channels pass through two
BPF filters, one of which has a Gilbert transform to give 90 deg delay. It's
the standard Phasing Method..

If you're asking about Binaural reception, it's the same as above, but less
the Hilbert transform so there's no sideband suppression..

Admittedly that page is somewhat condensed (simplified) over the original.

Regards .......... Zim ........ VK3GJZ