Date   

Re: .pdf Problem

Martin Phillips G4CIO
 

I've had the same problem sometimes. Download the file and it opens with Adobe reader but it won't via the browser (Firefox).

Martin/


On 22 January 2020 20:19:17 CET, "Michael Scott via Groups.Io" <g3lyp@...> wrote:
Hi All
 
Sorry this is a bit off topic, but opening the new Scatterpoint .pdf file reminded me. Quite often when I try to open a pdf file Windows 10 reports a problem and doesn’t open the file, and I have to try again and it always works at the second attempt. I had a look on Google but the usual solution suggested was to uninstall Adobe Reader and reload it. This seemed to work for a while, but in a short time the problem reappeared. This seems to be a problem with W10 as I never had it with XP which I used until I got a new computer.
 
Any suggestions would be appreciated!
 
73, Mike, G3LYP.

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.


Re: 23 cm yagi design

Paul Selwood G3YDY
 

Hi Reg,

That is how Peter Blair and the Mid Essex contest group did it for VHF Field Days late 60’s early 70’s – we usually won that band. I can remember operating that set up and on one occasion we did not bother to change the cable over just put the logging pen on the N connecter!!

Paul

G3YDY

 

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Reg Woolley via Groups.Io
Sent: 22 January 2020 19:06
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 23 cm yagi design

 

I remember as a School boy going up to the Mull of Galoway. To see the lads from the South of Scotland CG. Running a tripler and converter to get onto 23cms. Telling the other end to hang on as they did not have a relay. So to change from transmit to Receive,  they had to swap the connections over.

 

I guess that was around 1976 or 77.

 

Oh how things have changed 

 

Reg g8vhi 

 

 

 

Sent from Samsung tablet.

 

 

-------- Original message --------

From: Chris Bartram G4DGU <chris@...>

Date: 22/01/2020 10:00 (GMT+00:00)

Subject: Re: [UKMicrowaves] 23 cm yagi design

 

Hello Ben,

> AM hi.

Laugh you not! I know I'm by no means alone on this group in having made
my first QSOs on 23cm using AM! At that time in the radio medieval
(early 1970s) , the kit consisted of a HB valve transmitter on 2m, and
two cascaded varactor triplers from 2m. It's was probably a good thing
that I didn't then have a spectrum analyser!

Incidentally, I still have some affection for varactor technology. It
was much maligned, but used sensibly capable of very good performance.
The Russians, in particular, used varactors extensively, and I have some
which should allow quite high power on 47 and 76GHz if I ever find time
to design and build the kit. Retirement seems to mean that there are
even fewer hours in the day to play radio!

73

Chris G4DGU




This email has been scanned by BullGuard antivirus protection.
For more info visit www.bullguard.com


Re: Spectrum Analyser conundrum

Andy G4JNT
 

Not really.   The Rado Test set / 6GHz SA is a nice narrowband analyser, going down to 1Hz resolution.  It's a digital FFT based system.   SO the last thing I want to do is use an LO that wobbles by even a few hundred Hz.  My main interest is narrow band spectrum analysis.

As for a converter, the only YIG needed in there is the YIG fiilter to kill spuris mixer responses when used as a subharmonic mixer.   Need to find some way of tying in filter tuning with the display.  A PC is going to be involved in the loop I suspect.



On Wed, 22 Jan 2020 at 10:47, geoffrey pike via Groups.Io <gi0gdp=yahoo.co.uk@groups.io> wrote:
Would you not think of using a YIG oscillator instead of a synth?
cheers
Geoff
GI0GDP

On Tuesday, 21 January 2020, 20:27:05 GMT, Andy G4JNT <andy.g4jnt@...> wrote:


Openly Pondering ...

My Ailtech / Eaton 757   22GHz spectrum analyser has died.   Now, I could just dig inside and repair it - looks like the main PSU has failed somewhere, so probably is repairable, and I hate repairing stuff, especially old tech.   ANd then there's all the niggly faults which appeared over time, probably dried out capacitors to be  replaced.   The thing weighs over 30kg has already hurt my back in days gone by and is too long in the tooth and irritating to drive

I'd buy a half- decent SA but many popular ones only go to a few GHz and 22GHz ones are not cheap. I already have a modern digital radio test set that has a quite good narrow band SA function that goes to 6GHz  with span up to a GHz, so spending a fair bit of money on an SA that doesn't go much beyond this seems totally pointless.

NOW ...

I have two old YIG filters that tune 4 - 18GHz.  The Ailtech will have another one inside it, as well as a harmonic mixer so thoughts are turning to an external converter.    YIG filter, harmonic mixer and integer-N synth LO with some basic drive electronics.   Simple enough.   Could butcher the old SA for it's harmonic mixer, or make one using a uWave DBM with subharmonic LO.  It also has the switchable attenuator going to 20GHz + and possibly other uWave bits that may prove useful

So the decision to repair (tedious and not exciting) or rip apart for bits to make an external converter has to be made,

Has anyone done this - an external SA convertger?   Might generate a bit of interest in building RF stuff again here !

 


Re: .pdf Problem

Andy G4JNT
 

Web browsers open .PDFs as well. 
I use Google Chrome here and sometimes think it is a better tool than PDF reader.

Right click on the .PDF file  and see what you are offered under "Open With"



On Wed, 22 Jan 2020 at 19:19, Michael Scott via Groups.Io <g3lyp=btinternet.com@groups.io> wrote:
Hi All
 
Sorry this is a bit off topic, but opening the new Scatterpoint .pdf file reminded me. Quite often when I try to open a pdf file Windows 10 reports a problem and doesn’t open the file, and I have to try again and it always works at the second attempt. I had a look on Google but the usual solution suggested was to uninstall Adobe Reader and reload it. This seemed to work for a while, but in a short time the problem reappeared. This seems to be a problem with W10 as I never had it with XP which I used until I got a new computer.
 
Any suggestions would be appreciated!
 
73, Mike, G3LYP.


.pdf Problem

Michael Scott
 

Hi All
 
Sorry this is a bit off topic, but opening the new Scatterpoint .pdf file reminded me. Quite often when I try to open a pdf file Windows 10 reports a problem and doesn’t open the file, and I have to try again and it always works at the second attempt. I had a look on Google but the usual solution suggested was to uninstall Adobe Reader and reload it. This seemed to work for a while, but in a short time the problem reappeared. This seems to be a problem with W10 as I never had it with XP which I used until I got a new computer.
 
Any suggestions would be appreciated!
 
73, Mike, G3LYP.


Re: 23 cm yagi design

Reg Woolley
 

I remember as a School boy going up to the Mull of Galoway. To see the lads from the South of Scotland CG. Running a tripler and converter to get onto 23cms. Telling the other end to hang on as they did not have a relay. So to change from transmit to Receive,  they had to swap the connections over.

I guess that was around 1976 or 77.

Oh how things have changed 

Reg g8vhi 



Sent from Samsung tablet.


-------- Original message --------
From: Chris Bartram G4DGU <chris@...>
Date: 22/01/2020 10:00 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 23 cm yagi design

Hello Ben,

> AM hi.

Laugh you not! I know I'm by no means alone on this group in having made
my first QSOs on 23cm using AM! At that time in the radio medieval
(early 1970s) , the kit consisted of a HB valve transmitter on 2m, and
two cascaded varactor triplers from 2m. It's was probably a good thing
that I didn't then have a spectrum analyser!

Incidentally, I still have some affection for varactor technology. It
was much maligned, but used sensibly capable of very good performance.
The Russians, in particular, used varactors extensively, and I have some
which should allow quite high power on 47 and 76GHz if I ever find time
to design and build the kit. Retirement seems to mean that there are
even fewer hours in the day to play radio!

73

Chris G4DGU





Re: Input Needed for RadCom Column

Andy G4JNT
 

Yes, I did. 
'fraid I can't reply to everyone who comments.  Relevent emails will be placed in  their own folder pending...
 


On Wed, 22 Jan 2020 at 17:44, Paul G8KFW <paul@...> wrote:

Hi Andy

 

Did you receive my email to your email address regarding possible future copy for the  RadCom Column

 

Regards Paul


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Andy G4JNT
Sent: 22 January 2020 17:09
To: UK Microwaves groups.io
Subject: Re: [UKMicrowaves] Input Needed for RadCom Column

 

So. you're saying, for the olde-mann ident stage, it would be preferable to introduce a carefully designed, non-linear chirp along with a bit of PR noise.   That can be done with a PIC / DDS combination, so a direct upconversion based beacon should be able to manage it.   But a PLL or RDDS based one can't hack it

 

For all  the use the CW ident is, might as well do something special and use some artistry for its sound.

 

Now there's a thought for any GB3SC# update - a custom CW ident 

 

Andy

 

 

 

On Wed, 22 Jan 2020 at 17:01, Neil Smith G4DBN <neil@...> wrote:

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:

Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


Re: Input Needed for RadCom Column

Chris Bartram G4DGU
 

Hello Andy,

There seems to be no restriction on using a tone signaling system with tones or frequency offsets chosen from a series of frequencies related by 2e(1/12). That should give a nice quasi-musical character to beacon idents without upsetting those who run the system.

73

Chris G4DGU


On 22/01/2020 17:35, Andy G4JNT wrote:
Unfortunately, the old people who run the system still mandate CW idents.  I see no point whatsoever in them, but whatevs...

The period of plain carrier, also mandated,  is essential as it gives a constant measure for any beacon.

But the proper modulation type is a free-for-all.  So a combination of fast mode plus slow mode is quite possible.   JT9 woul dbe good for that as it can have a lot of generator code in common, just changing the symbol rate and tone shift .  In fact for uWaves,  the same tone shift for fast and slow mode could even be maintained.



Re: Input Needed for RadCom Column

Paul G8KFW
 

Hi Andy

 

Did you receive my email to your email address regarding possible future copy for the  RadCom Column

 

Regards Paul


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Andy G4JNT
Sent: 22 January 2020 17:09
To: UK Microwaves groups.io
Subject: Re: [UKMicrowaves] Input Needed for RadCom Column

 

So. you're saying, for the olde-mann ident stage, it would be preferable to introduce a carefully designed, non-linear chirp along with a bit of PR noise.   That can be done with a PIC / DDS combination, so a direct upconversion based beacon should be able to manage it.   But a PLL or RDDS based one can't hack it

 

For all  the use the CW ident is, might as well do something special and use some artistry for its sound.

 

Now there's a thought for any GB3SC# update - a custom CW ident 

 

Andy

 

 

 

On Wed, 22 Jan 2020 at 17:01, Neil Smith G4DBN <neil@...> wrote:

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:

Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


Re: Input Needed for RadCom Column

Andy G4JNT
 

Unfortunately, the old people who run the system still mandate CW idents.  I see no point whatsoever in them, but whatevs...

The period of plain carrier, also mandated,  is essential as it gives a constant measure for any beacon.

But the proper modulation type is a free-for-all.  So a combination of fast mode plus slow mode is quite possible.   JT9 woul dbe good for that as it can have a lot of generator code in common, just changing the symbol rate and tone shift .  In fact for uWaves,  the same tone shift for fast and slow mode could even be maintained.



On Wed, 22 Jan 2020 at 17:25, Neil Smith G4DBN <neil@...> wrote:

Something like the sound of a pump key with a CO/PA two-valve transmitter circa 1956 would do the job. Decent click, bit of droop, gradual drift, good amount of chirp, and a few character spacing and symbol length errors to add some idiosyncratic "swing".  Instant recognition of the "fist" without hearing more than a couple of characters.

Is a CWID actually required at all under the beacon licence?  The beacon could have a theme tune instead.  Local folk song melody, or a nice short ID like the Radio Tirana ident from the 70s.

I'd certainly be keen to have a decent slow mode like JT4F/G or PI4 which would work via rainscatter as well as weak troposcatter, but also a fast mode like JT9F-fast that would work off aircraft, and some plain carrier to look at the shape of the troposcatter spectrum over 20s or so.

Neil G4DBN

On 22/01/2020 17:09, Andy G4JNT wrote:
So. you're saying, for the olde-mann ident stage, it would be preferable to introduce a carefully designed, non-linear chirp along with a bit of PR noise.   That can be done with a PIC / DDS combination, so a direct upconversion based beacon should be able to manage it.   But a PLL or RDDS based one can't hack it

For all  the use the CW ident is, might as well do something special and use some artistry for its sound.

Now there's a thought for any GB3SC# update - a custom CW ident 



On Wed, 22 Jan 2020 at 17:01, Neil Smith G4DBN <neil@...> wrote:

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:
Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  
-- 
Neil
<a href="http://g4dbn.uk/"><small>g4dbn.uk</small></a>


Re: Input Needed for RadCom Column

Neil Smith G4DBN
 

Something like the sound of a pump key with a CO/PA two-valve transmitter circa 1956 would do the job. Decent click, bit of droop, gradual drift, good amount of chirp, and a few character spacing and symbol length errors to add some idiosyncratic "swing".  Instant recognition of the "fist" without hearing more than a couple of characters.

Is a CWID actually required at all under the beacon licence?  The beacon could have a theme tune instead.  Local folk song melody, or a nice short ID like the Radio Tirana ident from the 70s.

I'd certainly be keen to have a decent slow mode like JT4F/G or PI4 which would work via rainscatter as well as weak troposcatter, but also a fast mode like JT9F-fast that would work off aircraft, and some plain carrier to look at the shape of the troposcatter spectrum over 20s or so.

Neil G4DBN

On 22/01/2020 17:09, Andy G4JNT wrote:
So. you're saying, for the olde-mann ident stage, it would be preferable to introduce a carefully designed, non-linear chirp along with a bit of PR noise.   That can be done with a PIC / DDS combination, so a direct upconversion based beacon should be able to manage it.   But a PLL or RDDS based one can't hack it

For all  the use the CW ident is, might as well do something special and use some artistry for its sound.

Now there's a thought for any GB3SC# update - a custom CW ident 



On Wed, 22 Jan 2020 at 17:01, Neil Smith G4DBN <neil@...> wrote:

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:
Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  
-- 
Neil
<a href="http://g4dbn.uk/"><small>g4dbn.uk</small></a>


Re: Input Needed for RadCom Column

Andy G4JNT
 

So. you're saying, for the olde-mann ident stage, it would be preferable to introduce a carefully designed, non-linear chirp along with a bit of PR noise.   That can be done with a PIC / DDS combination, so a direct upconversion based beacon should be able to manage it.   But a PLL or RDDS based one can't hack it

For all  the use the CW ident is, might as well do something special and use some artistry for its sound.

Now there's a thought for any GB3SC# update - a custom CW ident 



On Wed, 22 Jan 2020 at 17:01, Neil Smith G4DBN <neil@...> wrote:

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:
Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  


Re: Input Needed for RadCom Column

Neil Smith G4DBN
 

It is a GLORIOUS sound Adrian, expecially after it has travelled 342km to reach here, which, as you know, it does quite often. I like PI7RTD as well, and all of the others the whoop and slide and chirp. Perfection is boring, at least for the CWID.

Neil G4DBN

On 22/01/2020 15:56, Adrian G4UVZ via Groups.Io wrote:
Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  
_._,_._,_



Spectrum Analysers for sale from SK

Neil, G3RIR
 

I have two spectrum analysers for sale on behalf of the widow of an old friend of mine.

One is a Marconi TF2370 110 MHz I believe

The other is Tektronics 7603 with 7L18 plug-in  1.5 - 18 GHz.

I do not know if either are working as I do not know enough about them. Therefore I do not know the value.

Both are heavy so really only collect from my QTH south Leicestershire very near jnctn 20 M!.

If any one is seriously interested I may be able to take them to the Harwell Rally 9th Feb.

Neil G3RIR


Re: Input Needed for RadCom Column

Adrian G4UVZ
 

Whilst the idea of keying the 5Mhz sounds interesting ..I fear that the df/dt of the keying by the time it had gone through the PLL would be  pretty poor..as you can hear the exisiting keying is no wonderful!  https://www.beaconspot.uk/beaconsnd.php?beaconcall=GB3KBQ  


Re: Input Needed for RadCom Column

Andy G4JNT
 

I once generated WSPR using a carefully adjusted varicap across a crystal, then drove it with a simple two-bit A/D (two resistors).   JT4x would work just as well (there's not a lot of difference between it and WSPR)

But still needed a PIC to generate the timing and symbols; you can't get away from having to use some sort of controller.   Unless...   You coded it onto a wheel with an opto coupler (dual channel of course for four levels)    But you still need PC software to calculate the symbol pattern and GPS or accurate clock time info.
  


On Wed, 22 Jan 2020 at 15:29, Adrian G4UVZ via Groups.Io <adrianwhatmore248=btinternet.com@groups.io> wrote:
A question rather than an answer!  A couple of years ago, as beacon keeper for GB3KBQ I wanted to bring the beacon into the 21st century. Whilst the existing system is very frequency stable using 35 year old  a Pye HS400  https://uhf-satcom.com/misc/hs400-reference-oscillator  and multiplying it's 27MHz o/p up to 10368.87 MHz . The FSK keying is very agricultural using a reed relay to offset the 5MHz TCXO. Having seen the benefits of JT4G modulation system in tests with Neil G4DBN, I was hoping that I might be able to get KBQ emitting these tones. Sadly I drew a blank on a suitable design. The beacon requires around 0dBm at 10GHz ..or 108MHz at a similar level.(Tone spacing woud have to be divided by 96)

For avoidance of any doubt ..whilst I can build hardware, measure rf levels and frequency accurately. Programming eproms, flash memory, PICs, programmable arrays etc is beyond my ability!

Perhaps an article addressing the above would be of interest to other beacon keepers?

Adrian  G4UVZ


Re: Input Needed for RadCom Column

Adrian G4UVZ
 

A question rather than an answer!  A couple of years ago, as beacon keeper for GB3KBQ I wanted to bring the beacon into the 21st century. Whilst the existing system is very frequency stable using 35 year old  a Pye HS400  https://uhf-satcom.com/misc/hs400-reference-oscillator  and multiplying it's 27MHz o/p up to 10368.87 MHz . The FSK keying is very agricultural using a reed relay to offset the 5MHz TCXO. Having seen the benefits of JT4G modulation system in tests with Neil G4DBN, I was hoping that I might be able to get KBQ emitting these tones. Sadly I drew a blank on a suitable design. The beacon requires around 0dBm at 10GHz ..or 108MHz at a similar level.(Tone spacing woud have to be divided by 96)

For avoidance of any doubt ..whilst I can build hardware, measure rf levels and frequency accurately. Programming eproms, flash memory, PICs, programmable arrays etc is beyond my ability!

Perhaps an article addressing the above would be of interest to other beacon keepers?

Adrian  G4UVZ


Re: Spectrum Analyser conundrum

geoffrey pike
 

Would you not think of using a YIG oscillator instead of a synth?
cheers
Geoff
GI0GDP

On Tuesday, 21 January 2020, 20:27:05 GMT, Andy G4JNT <andy.g4jnt@...> wrote:


Openly Pondering ...

My Ailtech / Eaton 757   22GHz spectrum analyser has died.   Now, I could just dig inside and repair it - looks like the main PSU has failed somewhere, so probably is repairable, and I hate repairing stuff, especially old tech.   ANd then there's all the niggly faults which appeared over time, probably dried out capacitors to be  replaced.   The thing weighs over 30kg has already hurt my back in days gone by and is too long in the tooth and irritating to drive

I'd buy a half- decent SA but many popular ones only go to a few GHz and 22GHz ones are not cheap. I already have a modern digital radio test set that has a quite good narrow band SA function that goes to 6GHz  with span up to a GHz, so spending a fair bit of money on an SA that doesn't go much beyond this seems totally pointless.

NOW ...

I have two old YIG filters that tune 4 - 18GHz.  The Ailtech will have another one inside it, as well as a harmonic mixer so thoughts are turning to an external converter.    YIG filter, harmonic mixer and integer-N synth LO with some basic drive electronics.   Simple enough.   Could butcher the old SA for it's harmonic mixer, or make one using a uWave DBM with subharmonic LO.  It also has the switchable attenuator going to 20GHz + and possibly other uWave bits that may prove useful

So the decision to repair (tedious and not exciting) or rip apart for bits to make an external converter has to be made,

Has anyone done this - an external SA convertger?   Might generate a bit of interest in building RF stuff again here !

 


Re: 23 cm yagi design

Chris Bartram G4DGU
 

Hello Ben,

AM hi.
Laugh you not! I know I'm by no means alone on this group in having made my first QSOs on 23cm using AM! At that time in the radio medieval (early 1970s) , the kit consisted of a HB valve transmitter on 2m, and two cascaded varactor triplers from 2m. It's was probably a good thing that I didn't then have a spectrum analyser!

Incidentally, I still have some affection for varactor technology. It was much maligned, but used sensibly capable of very good performance. The Russians, in particular, used varactors extensively, and I have some which should allow quite high power on 47 and 76GHz if I ever find time to design and build the kit. Retirement seems to mean that there are even fewer hours in the day to play radio!

73

Chris G4DGU


Re: 23 cm yagi design

militaryoperator
 


73

Chris G4DGU - who you last worked as GW4DGU on 5MHz AM! There's an
admission!


-=-=-=-=-=-=-=-=-=-=-=-

We'll try 23 next Chris, AM hi. 


cheers. Ben

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