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QST article needed please

Barry Chambers
 

Please would anyone have a copy of the following please?

Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers", QST, January 1978

Many thanks

-- 

73

Barry, G8AGN

Neil Smith G4DBN
 

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

  

Barry Chambers
 

Neil

Yes, that's the one. Many thanks for the very quick reply. Maybe an application for the 122 board Rx IQ outputs.

73

Barry, G8AGN
On 23/11/2019 16:10, Neil Smith G4DBN wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

Andy G4JNT
 

I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

  

Barry Chambers
 

Hi Andy

Thanks for the info. MC do one which has been used by VK5KK in his version of the 122 board. It's about $15 (plus any import etc)

73

Barry, G8AGN
On 23/11/2019 16:25, Andy G4JNT wrote:

I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

Andy G4JNT
 

Like just about every I/Q up converter I've seen, it has dual differential outputs.    While you can use a pair of matched baluns to go to single ended, and I've done this for a couple of projects, would like to find a design for a lumped element differential I/Q network with all four inputs used.

The old polyphase RC network was one such, designed for audio, so it ought to be possible with L/C at RF. 



On Sat, 23 Nov 2019 at 16:36, Barry Chambers <b.chambers@...> wrote:

Hi Andy

Thanks for the info. MC do one which has been used by VK5KK in his version of the 122 board. It's about $15 (plus any import etc)

73

Barry, G8AGN
On 23/11/2019 16:25, Andy G4JNT wrote:
I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

Barry Chambers
 

Hi Andy

I look forward to seeing what you come up with! That's another RC column sorted ?

73

Barry, G8AGN
On 23/11/2019 16:43, Andy G4JNT wrote:

Like just about every I/Q up converter I've seen, it has dual differential outputs.    While you can use a pair of matched baluns to go to single ended, and I've done this for a couple of projects, would like to find a design for a lumped element differential I/Q network with all four inputs used.

The old polyphase RC network was one such, designed for audio, so it ought to be possible with L/C at RF. 



On Sat, 23 Nov 2019 at 16:36, Barry Chambers <b.chambers@...> wrote:

Hi Andy

Thanks for the info. MC do one which has been used by VK5KK in his version of the 122 board. It's about $15 (plus any import etc)

73

Barry, G8AGN
On 23/11/2019 16:25, Andy G4JNT wrote:
I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

info@...
 

Hi this is what I have, let's hope it helps.
73 of IK5FGJ Raffaele

 

Da: UKMicrowaves@groups.io <UKMicrowaves@groups.io> Per conto di Barry Chambers
Inviato: sabato 23 novembre 2019 17:05
A: UKMicrowaves@groups.io
Oggetto: [UKMicrowaves] QST article needed please

 

Please would anyone have a copy of the following please?

Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers", QST, January 1978

Many thanks

-- 
 
73
 
Barry, G8AGN

Barry Chambers
 

Raffaele

Many thanks

73

Barry, G8AGN

Andy G4JNT
 

Had a think about it.
Instead of a four input network like the polyphase RC design, one resolution would be two standard hybrids followed by a 180 deg combiner.   See attached diagram

Since the chip outputs for most upconverters are designed for significantly higher than 50 ohms, the lumped element hybrids could be designed for a higher Zo then the combiner used for impedance tranformation as well.

Whether this is any better than two balun transformers and a single hybrid is debatable.

  
4PORTHYB.gif


On Sat, 23 Nov 2019 at 16:51, Barry Chambers <b.chambers@...> wrote:

Hi Andy

I look forward to seeing what you come up with! That's another RC column sorted ?

73

Barry, G8AGN
On 23/11/2019 16:43, Andy G4JNT wrote:
Like just about every I/Q up converter I've seen, it has dual differential outputs.    While you can use a pair of matched baluns to go to single ended, and I've done this for a couple of projects, would like to find a design for a lumped element differential I/Q network with all four inputs used.

The old polyphase RC network was one such, designed for audio, so it ought to be possible with L/C at RF. 



On Sat, 23 Nov 2019 at 16:36, Barry Chambers <b.chambers@...> wrote:

Hi Andy

Thanks for the info. MC do one which has been used by VK5KK in his version of the 122 board. It's about $15 (plus any import etc)

73

Barry, G8AGN
On 23/11/2019 16:25, Andy G4JNT wrote:
I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers

Barry Chambers
 

Andy

I guess we won't know whether any of these approaches work until we have 122 boards to play with?

Barry

On 24/11/2019 16:27, Andy G4JNT wrote:
Had a think about it.
Instead of a four input network like the polyphase RC design, one resolution would be two standard hybrids followed by a 180 deg combiner.   See attached diagram

Since the chip outputs for most upconverters are designed for significantly higher than 50 ohms, the lumped element hybrids could be designed for a higher Zo then the combiner used for impedance tranformation as well.

Whether this is any better than two balun transformers and a single hybrid is debatable.

  
4PORTHYB.gif


On Sat, 23 Nov 2019 at 16:51, Barry Chambers <b.chambers@...> wrote:

Hi Andy

I look forward to seeing what you come up with! That's another RC column sorted ?

73

Barry, G8AGN
On 23/11/2019 16:43, Andy G4JNT wrote:
Like just about every I/Q up converter I've seen, it has dual differential outputs.    While you can use a pair of matched baluns to go to single ended, and I've done this for a couple of projects, would like to find a design for a lumped element differential I/Q network with all four inputs used.

The old polyphase RC network was one such, designed for audio, so it ought to be possible with L/C at RF. 



On Sat, 23 Nov 2019 at 16:36, Barry Chambers <b.chambers@...> wrote:

Hi Andy

Thanks for the info. MC do one which has been used by VK5KK in his version of the 122 board. It's about $15 (plus any import etc)

73

Barry, G8AGN
On 23/11/2019 16:25, Andy G4JNT wrote:
I did one for 8.5MHz as the IF for this http://g4jnt.com/24G_IQ_beacon_source.pdf   using a bifilar wound iron dust core
Remarkably good results.

Not sure it would be quite so easy to get going at 100 - 200MHz which I assume you're thinking about for the 122GHz Rx
Could just buy a MiniCircuits ready made hybrid



On Sat, 23 Nov 2019 at 16:11, Neil Smith G4DBN <neil@...> wrote:

http://www.cqham.ru/forum/attachment.php?attachmentid=203217&d=1432904617

Is that the one?

Neil

On 23/11/2019 16:05, Barry Chambers wrote:
Reed Fisher (W2CQH), "Twisted-Wire Quadrature Hybrid Directional Couplers
-- 
73
Barry, G8AGN