TAYLOE DETECTOR


RICK PHILLIPS
 

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH



Bob Macklin <macklinbob@...>
 

You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH



Hans Summers
 

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH




Bob Macklin <macklinbob@...>
 

I sent the wrong link for the Softrock Ensemble receiver in my previous post.
 
The correct link is:
 
The kit version is here:
 
The kit used both through-hole parts and surface mount parts.
 
This receiver has a USB interface to a SI-570 VFO. There are several good PC programs to control it.
 
Performance of the Tayloe detector depends heavily on the sound card in your computer.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Saturday, July 15, 2017 10:40 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH




Alan
 

There are lots of pages on the web, one https://www.arrl.org/files/file/Technology/tis/info/pdf/020708qex013.pdf More with a search

Most soundcard SDRs use the Tayloe, the QRP Labs receiver is possibly better than the Softrock using all 4 90° phases.

73 Alan G4ZFQ


Bob Macklin <macklinbob@...>
 

The Softrock Ensemble receiver is a 4 band receiver with a VFO controlled by
a USB connection.

It seems to be a pretty good receiver. But performance will depend on your
soundcard.

And these soundcard receivers may not work with a laptop computer unless you
have an external (USB) soundcard.

Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
From: "Alan via Groups.Io" <alan4alan@...>
To: <QRPLabs@groups.io>
Sent: Saturday, July 15, 2017 11:52 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR


There are lots of pages on the web, one
https://www.arrl.org/files/file/Technology/tis/info/pdf/020708qex013.pdf
More with a search

Most soundcard SDRs use the Tayloe, the QRP Labs receiver is possibly
better than the Softrock using all 4 90° phases.

73 Alan G4ZFQ



Alan
 

Bob,

Yes, I have used Softrocks for 10 years or more.
But this is the QRP Labs group and a similar receiver is produced.
It is not as versatile as the Softrock but has a far tighter BPF and the difference in the Tayloe is actually that instrumentation amplifiers are used. It may be used with the QRP Labs VFO but so far no direct computer control.
But it is produced to compliment the U3.

Personally I'm not so sure about soundcards, most stereo ones will produce good results. I do not usually see a great difference with better cards but that probably depends on how critical you are.

73 Alan G4ZFQ

The Softrock Ensemble receiver is a 4 band receiver with a VFO controlled by
a USB connection.
It seems to be a pretty good receiver. But performance will depend on your
soundcard.


Bob Macklin <macklinbob@...>
 

Alan,

The problem with soundcards are two.

The sample rate determines how wide a band you can receive with a single LO
setting. With a 96KB sample rate you get a 96KHz bandwidth. With a 192KB
sample rate you get a 192 KHz bandwidth. And some older computers only have
48KB sample rate. That only gives you a 48KHz bandwidth. That's not very
good.

The bigger problem is the ADC. Many sound cards and motherboards only have
16bit ADCs. That limit the dynamic range/sensitivity. Better sound cards
have 24 bit ADCs. That's what you really need for a SDR

The disadvantage of the QRP-Labs VFO is it was not designed for computer
control (USB). That's the nice feature of the Softrock Ensemble. Plus the
Softrock Ensemble is a 4 band receiver.

Hans sent me a QRP-Labs VFO kit to experiment with. I want a VFO that has
independent transmitter and receiver tuning (RIT). I also want a USB
Computer interface. The current design uses the serial input for the GPS
input. That will have to be multiplexed. Or I can go to a CPU that has
multiple serial ports. There is an Arduino board that does that.

I have not played with the weak signal stuff that seems to be the primary
interest of the QRP-Labs group.

Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
From: "Alan via Groups.Io" <alan4alan@...>
To: <QRPLabs@groups.io>
Sent: Sunday, July 16, 2017 12:37 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR


Bob,

Yes, I have used Softrocks for 10 years or more.
But this is the QRP Labs group and a similar receiver is produced.
It is not as versatile as the Softrock but has a far tighter BPF and the
difference in the Tayloe is actually that instrumentation amplifiers are
used. It may be used with the QRP Labs VFO but so far no direct computer
control.
But it is produced to compliment the U3.

Personally I'm not so sure about soundcards, most stereo ones will produce
good results. I do not usually see a great difference with better cards
but that probably depends on how critical you are.

73 Alan G4ZFQ

The Softrock Ensemble receiver is a 4 band receiver with a VFO controlled
by
a USB connection.

It seems to be a pretty good receiver. But performance will depend on
your
soundcard.



Alan
 

The sample rate determines how wide a band you can receive with a single LO
setting.
Bob,

Many are happy with 48KHz. In my opinion it does not really matter with a VFO. Yes, others want more.
The QRP Labs RX is fundamentally intended as a single channel RX

The bigger problem is the ADC. Many sound cards and motherboards only have
16bit ADCs. That limit the dynamic range/sensitivity. Better sound cards
have 24 bit ADCs.
But the dynamic range advantage of 24 bit cards is not achieved by unmodified Softrocks as their gain is optimised for 16 bit cards. Read the posts from Leif on the Softrock group.
But even 16 bits gives an impressive dynamic range.
I suspect this is also the case for the QRP Labs RX.
The gain of the SDR front end defines sensitivity, basically if antenna noise is seen then it is sensitive enough.

independent transmitter and receiver tuning (RIT).
This would be part of a SDR program, not hardware.

I also want a USB> Computer interface.
It would be a way of extending the use of the QRP Labs RX. I have used a Si570 as in the Softrock. There is a published method using a USB Trinket and HDSDR to control a Si5351 https://ceworkbench.wordpress.com/2016/03/24/controlling-the-si5351-signal-generator-from-hdsdr/ but I've not yet mastered programming a Trinket.

73 Alan G4ZFQ


Bob Macklin <macklinbob@...>
 

Alan,

I use the contests to test receivers.

This fall I will be testing the Softrock Ensemble on both 16 bit and 24 bit
systems.

My Softrock Ensemble sees the minimum my signal generator puts out on a 16
bit system. And I have only been playing with it for maybe a year now. I
normally use good real receivers. But I want one with computer control. And
I am not modifying any of my real receivers.

Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
From: "Alan via Groups.Io" <alan4alan@...>
To: <QRPLabs@groups.io>
Sent: Sunday, July 16, 2017 2:22 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR



The sample rate determines how wide a band you can receive with a single
LO
setting.
Bob,

Many are happy with 48KHz. In my opinion it does not really matter with a
VFO. Yes, others want more.
The QRP Labs RX is fundamentally intended as a single channel RX

The bigger problem is the ADC. Many sound cards and motherboards only
have
16bit ADCs. That limit the dynamic range/sensitivity. Better sound cards
have 24 bit ADCs.
But the dynamic range advantage of 24 bit cards is not achieved by
unmodified Softrocks as their gain is optimised for 16 bit cards. Read the
posts from Leif on the Softrock group.
But even 16 bits gives an impressive dynamic range.
I suspect this is also the case for the QRP Labs RX.
The gain of the SDR front end defines sensitivity, basically if antenna
noise is seen then it is sensitive enough.

independent transmitter and receiver tuning (RIT).
This would be part of a SDR program, not hardware.

I also want a USB> Computer interface.
It would be a way of extending the use of the QRP Labs RX. I have used a
Si570 as in the Softrock. There is a published method using a USB Trinket
and HDSDR to control a Si5351
https://ceworkbench.wordpress.com/2016/03/24/controlling-the-si5351-signal-generator-from-hdsdr/
but I've not yet mastered programming a Trinket.

73 Alan G4ZFQ







RICK PHILLIPS
 

Bob,

Thank you for the reply.  It seems as though the built version is better for me because I don't have experience with SMD devices.  Does the hf receiver have a built in vfo or do you need another kit for the vfo. 


I am more interested in how the Tayloe detector works and how IQ modulation is used for transmission and reception of digital, am, fm, and ssb signals.  On Youtube, W2AEW had a good video on IQ modulation.  I am still not clear how the Tayloe detector separates the incoming quadrature signal and gives you an output at 1/4 the incoming frequency with each of the cardinal phases of the waveform.


Richard Phillips

On July 16, 2017 at 2:28 AM Bob Macklin <macklinbob@...> wrote:

I sent the wrong link for the Softrock Ensemble receiver in my previous post.
 
The correct link is:
 
The kit version is here:
 
The kit used both through-hole parts and surface mount parts.
 
This receiver has a USB interface to a SI-570 VFO. There are several good PC programs to control it.
 
Performance of the Tayloe detector depends heavily on the sound card in your computer.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 10:40 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH


 

 


 


 


Bob Macklin <macklinbob@...>
 

Richard,
 
The Softrock Ensemble doe include the VFO. It is a SI-570 and is controlled by the SDR software on your computer.
 
The Softrock receiver should allow you to learn about the Tayloe detector.
 
The four phase clock is generated by a primary clock (the VFO) running at 4 times the frequency you want for the LO. This generates the 4 samples 90 degrees apart that are fed to the computer. The rest of the magic is done in the computer.
 
If you are interested in the reverse process for transmitting you might try the transmitter/receiver version.  have not tried it yet.
 
To really understand the way this works you will need to do a lot of reading. If you want to work on the hardware you will need a good scope.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Sunday, July 16, 2017 4:03 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

Bob,

Thank you for the reply.  It seems as though the built version is better for me because I don't have experience with SMD devices.  Does the hf receiver have a built in vfo or do you need another kit for the vfo. 


I am more interested in how the Tayloe detector works and how IQ modulation is used for transmission and reception of digital, am, fm, and ssb signals.  On Youtube, W2AEW had a good video on IQ modulation.  I am still not clear how the Tayloe detector separates the incoming quadrature signal and gives you an output at 1/4 the incoming frequency with each of the cardinal phases of the waveform.


Richard Phillips

On July 16, 2017 at 2:28 AM Bob Macklin <macklinbob@...> wrote:

I sent the wrong link for the Softrock Ensemble receiver in my previous post.
 
The correct link is:
 
The kit version is here:
 
The kit used both through-hole parts and surface mount parts.
 
This receiver has a USB interface to a SI-570 VFO. There are several good PC programs to control it.
 
Performance of the Tayloe detector depends heavily on the sound card in your computer.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 10:40 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH



 


 



 


 


RICK PHILLIPS
 

Bob,

Very good.  I'm doing the reading part now.  I read a paper by Dan Tayloe about the Tayloe detector.  He has a schematic of his Tayloe detector on the back page.  If I don't try to go too deep, I think that I have a grasp on what he is doing.  However, I don't quite have it together on how the I and Q signals are produced by sampling the 0, 90, 180, and 270 degree parts of the sine (or cosine wave?).  In fact, I am not sure how the I and Q signals can represent the different modes of analog radio transmission.  I know that you add the I and Q signals at the transmitter to produce a signal that varies in phase.  I am not sure about the receiving side.  I guess that the Tayloe detector eliminates the need for a reference clock.  I know that I can't learn this over night, but what a adventure in trying to learn this stuff.   I am planning to purchase the SoftRock RX Ensemble II Receiver a little bit later.  Thanks again for your advice.


Richard Phillips

On July 16, 2017 at 10:23 AM Bob Macklin <macklinbob@...> wrote:

Richard,
 
The Softrock Ensemble doe include the VFO. It is a SI-570 and is controlled by the SDR software on your computer.
 
The Softrock receiver should allow you to learn about the Tayloe detector.
 
The four phase clock is generated by a primary clock (the VFO) running at 4 times the frequency you want for the LO. This generates the 4 samples 90 degrees apart that are fed to the computer. The rest of the magic is done in the computer.
 
If you are interested in the reverse process for transmitting you might try the transmitter/receiver version.  have not tried it yet.
 
To really understand the way this works you will need to do a lot of reading. If you want to work on the hardware you will need a good scope.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Sunday, July 16, 2017 4:03 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

Bob,

Thank you for the reply.  It seems as though the built version is better for me because I don't have experience with SMD devices.  Does the hf receiver have a built in vfo or do you need another kit for the vfo. 


I am more interested in how the Tayloe detector works and how IQ modulation is used for transmission and reception of digital, am, fm, and ssb signals.  On Youtube, W2AEW had a good video on IQ modulation.  I am still not clear how the Tayloe detector separates the incoming quadrature signal and gives you an output at 1/4 the incoming frequency with each of the cardinal phases of the waveform.


Richard Phillips

On July 16, 2017 at 2:28 AM Bob Macklin <macklinbob@...> wrote:

I sent the wrong link for the Softrock Ensemble receiver in my previous post.
 
The correct link is:
 
The kit version is here:
 
The kit used both through-hole parts and surface mount parts.
 
This receiver has a USB interface to a SI-570 VFO. There are several good PC programs to control it.
 
Performance of the Tayloe detector depends heavily on the sound card in your computer.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 10:40 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH



 


 



 


 


 


Bob Macklin <macklinbob@...>
 

Rick,
 
The 0  and 180 degree signals are the"I" (IN PHASE) and the 90 and 270 degree signals are the "Q" (QUADERATURE).
 
From there the decoding is done by the software in the computer.
 
Check out Rocky and HDSDR. Rocky is a very simple SDR program and HDSDR is a very complex SDR program.
 
Start with Rocky.
 
You don't need to worry about the transmitting until you understand the receiving.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Sunday, July 16, 2017 12:13 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

Bob,

Very good.  I'm doing the reading part now.  I read a paper by Dan Tayloe about the Tayloe detector.  He has a schematic of his Tayloe detector on the back page.  If I don't try to go too deep, I think that I have a grasp on what he is doing.  However, I don't quite have it together on how the I and Q signals are produced by sampling the 0, 90, 180, and 270 degree parts of the sine (or cosine wave?).  In fact, I am not sure how the I and Q signals can represent the different modes of analog radio transmission.  I know that you add the I and Q signals at the transmitter to produce a signal that varies in phase.  I am not sure about the receiving side.  I guess that the Tayloe detector eliminates the need for a reference clock.  I know that I can't learn this over night, but what a adventure in trying to learn this stuff.   I am planning to purchase the SoftRock RX Ensemble II Receiver a little bit later.  Thanks again for your advice.


Richard Phillips

On July 16, 2017 at 10:23 AM Bob Macklin <macklinbob@...> wrote:

Richard,
 
The Softrock Ensemble doe include the VFO. It is a SI-570 and is controlled by the SDR software on your computer.
 
The Softrock receiver should allow you to learn about the Tayloe detector.
 
The four phase clock is generated by a primary clock (the VFO) running at 4 times the frequency you want for the LO. This generates the 4 samples 90 degrees apart that are fed to the computer. The rest of the magic is done in the computer.
 
If you are interested in the reverse process for transmitting you might try the transmitter/receiver version.  have not tried it yet.
 
To really understand the way this works you will need to do a lot of reading. If you want to work on the hardware you will need a good scope.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Sunday, July 16, 2017 4:03 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

Bob,

Thank you for the reply.  It seems as though the built version is better for me because I don't have experience with SMD devices.  Does the hf receiver have a built in vfo or do you need another kit for the vfo. 


I am more interested in how the Tayloe detector works and how IQ modulation is used for transmission and reception of digital, am, fm, and ssb signals.  On Youtube, W2AEW had a good video on IQ modulation.  I am still not clear how the Tayloe detector separates the incoming quadrature signal and gives you an output at 1/4 the incoming frequency with each of the cardinal phases of the waveform.


Richard Phillips

On July 16, 2017 at 2:28 AM Bob Macklin <macklinbob@...> wrote:

I sent the wrong link for the Softrock Ensemble receiver in my previous post.
 
The correct link is:
 
The kit version is here:
 
The kit used both through-hole parts and surface mount parts.
 
This receiver has a USB interface to a SI-570 VFO. There are several good PC programs to control it.
 
Performance of the Tayloe detector depends heavily on the sound card in your computer.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 10:40 PM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

A small correction...

The Tayloe Detector (a.k.a. Quadrature Sampling Detector) uses a 2-phase clock AT the operating frequency. Not at 4x The operating frequency. 

An oscillator signal at 4x the operating frequency is often used to generate the correct 90-degree phase offset 2nd phase clock signal. For example the QRP Labs receiver module http://qrp-labs.com 

It is also possible to use an oscillator like the Si5351A synthesizer chip, which has multiple outputs. You can configure two of these outputs to be at the operating frequency with a 90-degree phase offset between them. See http://qrp-labs.com/bro

73 Hans G0UPL 


On Jul 15, 2017 23:04, "Bob Macklin" <macklinbob@...> wrote:
You might be better off to start with a Softrock Ensemble kit. Or buy an assembled Softrock Ensemble. Then learn how to make it work with available software.
 
 
The Tyloe Detector works on a 2 phase clock operating at 4 times the frequency.
 
There is also a Softrock Yahoo group.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message -----
Sent: Saturday, July 15, 2017 9:50 AM
Subject: [QRPLabs] TAYLOE DETECTOR

Hello,
Thank you for letting me join QRPLabs.  I would like to learn more about the Tayloe detector.  I have done some reading on the Tayloe detector, but there are some things that I don't understand fully.  I am having trouble with how the detector captures the 0, 90, 180, 270 degree segments of the input signal at 4 times the frequency.  My guess is that I need to review RC time constants. 

I originally wanted to build my own Tayloe detector using discrete parts in order to see how it works.  I found the QRPLabs website and found the information on the SDR receiver module and the VFO Signal Generator.  I think that I would have better results with the kits rather than building my own Tayloe detector.  I would appreciate any advice from the QRPLabs members. 

I hope to understand IQ modulation works with both transmitting and receiving and explain the principles of IQ modulation in an intuitive way to members of my Amateur Radio club. 

Thank you,

Richard Phillips
WA9MTH



 


 



 


 


 


Eric Smith
 

On Jul 16, 2017 1:15 PM, "RICK PHILLIPS" <raphillips5@...> wrote:

  I am not sure about the receiving side.  I guess that the Tayloe detector eliminates the need for a reference clock.

It doesn't. The Taylor detector separates the received signal into in-phase and quadrature signals (I and Q) relative to an oscillator in the receiver, but that isn't necessarily in phase with the transmitter, unless some other means is used to synchronize the transmitter and receiver oscillators, and that usually isn't done at this point in the receiver chain.

Since the phase doesn't match, the I and Q output of the Tayloe detector contains the same signal content as was transmitted, but the phase is rotated arbitrarily, and that phase rotation drifts. If you're trying to demodulate something where phase is unimportant, such as FSK or voice, it's not a problem. If you're trying to demodulate PSK modulations that use relative phase shifts, it's not a problem for that, either.

If you're demodulating something where the absolute phase matters, such as QAM or OFDM, then your SDR software has to do some form of carrier phase tracking, and rotate the received I and Q samples back to the "correct" phase. This might be done by the transmitter establishing the reference phase using a preamble at the start of transmission, or periodically within the transmission, or on a separate pilot carrier (eg in OFDM modulation).


RICK PHILLIPS
 

Eric,

This is what I originally thought.  I was wondering about synchronizing the transmitter and receiver. 


Thanks,

Richard Phillips

On July 16, 2017 at 4:10 PM Eric Smith <spacewar@...> wrote:

On Jul 16, 2017 1:15 PM, "RICK PHILLIPS" <raphillips5@...> wrote:

  I am not sure about the receiving side.  I guess that the Tayloe detector eliminates the need for a reference clock.

It doesn't. The Taylor detector separates the received signal into in-phase and quadrature signals (I and Q) relative to an oscillator in the receiver, but that isn't necessarily in phase with the transmitter, unless some other means is used to synchronize the transmitter and receiver oscillators, and that usually isn't done at this point in the receiver chain.

Since the phase doesn't match, the I and Q output of the Tayloe detector contains the same signal content as was transmitted, but the phase is rotated arbitrarily, and that phase rotation drifts. If you're trying to demodulate something where phase is unimportant, such as FSK or voice, it's not a problem. If you're trying to demodulate PSK modulations that use relative phase shifts, it's not a problem for that, either.

If you're demodulating something where the absolute phase matters, such as QAM or OFDM, then your SDR software has to do some form of carrier phase tracking, and rotate the received I and Q samples back to the "correct" phase. This might be done by the transmitter establishing the reference phase using a preamble at the start of transmission, or periodically within the transmission, or on a separate pilot carrier (eg in OFDM modulation).


WB8LZR - Ron <ron@...>
 

On Sun, Jul 16, 2017 at 01:43 am, Bob Macklin wrote:
The disadvantage of the QRP-Labs VFO is it was not designed for computer
control (USB). That's the nice feature of the Softrock Ensemble. Plus the
Softrock Ensemble is a 4 band receiver.
Is that still true of the Qrp-Labs VFO?   The Prog-rock kit was changed to facilitate serial control in mid April or May?  I'm able to use a USB-2-serial cable, coupled with an RS-232/TTL converter to control my (just received) Progrock's frequency.  Perhaps the VFO kit may not yet include the firmware changes for serial op ...

Or, are you talking about more control than just setting the frequency registers?





Bob Macklin <macklinbob@...>
 

The QRP-Labs VFO uses the ATmega Rx pin for input from the GPS. The Tx out is not connected to anything.
 
I am redesigning the QRP-Labs VFO to enable USB input/output so it can be set from a computer.
 
I am also redesigning it for independent VFOs for transmitting and receiving.
 
I am considering making a more complex VFO by using the ATmeaga2568 chip. It has 4 serial ports. It would allow a host USB and the GPS.
 
The Arduino MEGA has the ATmega2568 chip.
 
This will be my next project.
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Monday, July 17, 2017 10:19 AM
Subject: Re: [QRPLabs] TAYLOE DETECTOR

On Sun, Jul 16, 2017 at 01:43 am, Bob Macklin wrote:
The disadvantage of the QRP-Labs VFO is it was not designed for computer
control (USB). That's the nice feature of the Softrock Ensemble. Plus the
Softrock Ensemble is a 4 band receiver.
Is that still true of the Qrp-Labs VFO?   The Prog-rock kit was changed to facilitate serial control in mid April or May?  I'm able to use a USB-2-serial cable, coupled with an RS-232/TTL converter to control my (just received) Progrock's frequency.  Perhaps the VFO kit may not yet include the firmware changes for serial op ...

Or, are you talking about more control than just setting the frequency registers?





Eric Smith
 

On Jul 17, 2017 5:49 AM, "RICK PHILLIPS" <raphillips5@...> wrote:

this is what I originally thought.  I was wondering about synchronizing the transmitter and receiver.  

In the days before DSP or SDR, one might have used a VCO to control the Tayloe detector, and controlled that based on carrier phase tracking from a demodulator. However, with DSP, SDR, etc., it is easier just to run the Tayloe on the local oscillator without attempting to track the transmitter phase, and apply any phase rotation (if needed) in the digital domain to the sampled I and Q data.

In practice, before DSP and SDR, modulations where absolute phase was necessary were not commonly used, at least in part to spare the expense of this added complexity.

In the early days of DSP it was more common to use a Hilbert Transform to filter the receive signal into I and Q, rather than a Tayloe detector.


RICK PHILLIPS
 

Eric,

This sounds complicated.  I have a few books on DSP.  I feel that I need more mathematics knowledge to understand the books.  My  hope was to learn by doing.  I might not understand this on an engineering level, but I would like to have an intuitive understanding on SDR.  I appreciate your explanation.   We had a talk on SDR at our ham radio club.  The talk went into SDR a little, but with not much information on how I Q modulation works.  I would like to understand this better.  I am beginning to think that the first suggestion I received might be a good idea.  This was to learn how to work with the software.  However, there is a lot I need to learn. 


Richard Phillips

On July 17, 2017 at 3:51 PM Eric Smith <spacewar@...> wrote:

On Jul 17, 2017 5:49 AM, "RICK PHILLIPS" <raphillips5@...> wrote:

this is what I originally thought.  I was wondering about synchronizing the transmitter and receiver.  

In the days before DSP or SDR, one might have used a VCO to control the Tayloe detector, and controlled that based on carrier phase tracking from a demodulator. However, with DSP, SDR, etc., it is easier just to run the Tayloe on the local oscillator without attempting to track the transmitter phase, and apply any phase rotation (if needed) in the digital domain to the sampled I and Q data.

In practice, before DSP and SDR, modulations where absolute phase was necessary were not commonly used, at least in part to spare the expense of this added complexity.

In the early days of DSP it was more common to use a Hilbert Transform to filter the receive signal into I and Q, rather than a Tayloe detector.