Date   

Re: Region 2 Sky Dish

Christopher Bartram <cbartram@...>
 

Hello John,

Unless somebody does a proper set of measurements, or finds an authoritative paper on the design, we'll never know for sure!

My understanding of the dish shape is that it was conceived as a way of coping with several feeds installed along the 'horizontal' axis to enable it to be used for multi-satellite feeds with minimum gain loss, and that it tends to a spherical, rather than parabolic, contour on that axis. That would allow the use of a line feed, rather like Arecibo, or several more conventional horns. However, I can also see the contrary argument ...

73

Chris GW4DGU






Chris surely you mean it's designed to NARROW the horizontal beamwidth to acommodate closely space sats in the Clarke belt.



-- 


Re: WG11 flanges

 

I have a 3" length of copper waveguide with two brass flanges in my scrap metal bin if you want it.

Ken G3YKI


Re: Region 2 Sky Dish

g4bao
 

Chris surely you mean it's designed to NARROW the horizontal beamwidth to acommodate closely space sats in the Clarke belt.

73
John



On 29 May 2017 at 15:57, Christopher Bartram cbartram@... [ukmicrowaves] <ukmicrowaves@...> wrote:
 

Hello Geoff

It should make very little difference. While the spacing is ~0.1WL, it's not really like a conventional mesh dish, as there is a lot more material between the holes. Alternatively, the feed may well be wrong: there's little information available on that dish, and it would be interesting if someone were to try to understand it fully. My attitude after looking at a couple of samples has been to to use conventional offset dishes, as they are much easier to understand!

I have seen observations that these dishes start to loose efficiency at 24GHz and that's been ascribed to the perforations, but it could also be due to the use of an inappropriate dish feed, or the dish not actually having a parabolic profile. I have a strong suspicion that the Sky dish is shaped so as to widen the horizontal beamwidth (as it's usually mounted) and the dish feeds we use are probably not particularly appropriate for that.

There are some particularly apposite articles by Dick Knadle, K2RIW, in the soon to be electronically republished version of 'Backscatter', a digest of technical information from 'Scatterpoint' 1999 - 2006.

73

Chris
GW4DGU

Does the measured 6mm spacing of the perfs in these dishes case problems using
it for 5.7 GHz
This is what i use and it only occured to me to measure the spacing after yesterdays
outing to the North Antrim hills.
thanks
Geoff
GI0GDP



Re: Region 2 Sky Dish

geoffrey pike
 

Hi Chris,
Well i was just wanting to be sure that it wasn't an issue, however the horn feed i'am using maybe worth improving on.
thanks
Geoff


On Monday, 29 May 2017, 15:57, "Christopher Bartram cbartram@... [ukmicrowaves]" wrote:


 
Hello Geoff
It should make very little difference. While the spacing is ~0.1WL, it's not really like a conventional mesh dish, as there is a lot more material between the holes. Alternatively, the feed may well be wrong: there's little information available on that dish, and it would be interesting if someone were to try to understand it fully. My attitude after looking at a couple of samples has been to to use conventional offset dishes, as they are much easier to understand!
I have seen observations that these dishes start to loose efficiency at 24GHz and that's been ascribed to the perforations, but it could also be due to the use of an inappropriate dish feed, or the dish not actually having a parabolic profile. I have a strong suspicion that the Sky dish is shaped so as to widen the horizontal beamwidth (as it's usually mounted) and the dish feeds we use are probably not particularly appropriate for that.
There are some particularly apposite articles by Dick Knadle, K2RIW, in the soon to be electronically republished version of 'Backscatter', a digest of technical information from 'Scatterpoint' 1999 - 2006.

73

Chris
GW4DGU

Does the measured 6mm spacing of the perfs in these dishes case problems using
it for 5.7 GHz
This is what i use and it only occured to me to measure the spacing after yesterdays
outing to the North Antrim hills.
thanks
Geoff
GI0GDP



Region 2 Sky Dish

Christopher Bartram <cbartram@...>
 

Hello Geoff

It should make very little difference. While the spacing is ~0.1WL, it's not really like a conventional mesh dish, as there is a lot more material between the holes. Alternatively, the feed may well be wrong: there's little information available on that dish, and it would be interesting if someone were to try to understand it fully. My attitude after looking at a couple of samples has been to to use conventional offset dishes, as they are much easier to understand!

I have seen observations that these dishes start to loose efficiency at 24GHz and that's been ascribed to the perforations, but it could also be due to the use of an inappropriate dish feed, or the dish not actually having a parabolic profile. I have a strong suspicion that the Sky dish is shaped so as to widen the horizontal beamwidth (as it's usually mounted) and the dish feeds we use are probably not particularly appropriate for that.

There are some particularly apposite articles by Dick Knadle, K2RIW, in the soon to be electronically republished version of 'Backscatter', a digest of technical information from 'Scatterpoint' 1999 - 2006.

73

Chris
GW4DGU

Does the measured 6mm spacing of the perfs in these dishes case problems using
it for 5.7 GHz
This is what i use and it only occured to me to measure the spacing after yesterdays
outing to the North Antrim hills.
thanks
Geoff
GI0GDP


Re: WG11 flanges

Noel G8GTZ
 

Thanks Gary – I will PM you.

Just need a 2nd one now...

73 Noel – G8GTZ

 

From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: Monday, May 29, 2017 1:41 PM
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] WG11 flanges

 

 

Hi Noel. 

 

I have one transition, I don't need it right now, so happy to loan it. 

 

I'll take a look in my other 3.4GHz box to make sure I don't have two. 

 

Gary M1EGI 

 

 

On 29 May 2017 09:59, "'Noel Matthews' noel@... [ukmicrowaves]" <ukmicrowaves@...> wrote:

 

I’m looking for a couple of WG11 (3.4GHz) to N type flanges, either to borrow for a few days (preferred) or buy.

Has anyone got anything they will part with?

73

Noel – G8GTZ

 


Re: WG11 flanges

Gary M1EGI
 

Hi Noel. 

I have one transition, I don't need it right now, so happy to loan it. 

I'll take a look in my other 3.4GHz box to make sure I don't have two. 

Gary M1EGI 


On 29 May 2017 09:59, "'Noel Matthews' noel@... [ukmicrowaves]" <ukmicrowaves@...> wrote:
 

I’m looking for a couple of WG11 (3.4GHz) to N type flanges, either to borrow for a few days (preferred) or buy.

Has anyone got anything they will part with?

73

Noel – G8GTZ



Re: WG11 flanges

Dr. David Kirkby (Kirkby Microwave Ltd) <drkirkby@...>
 

On 29 May 2017 at 09:59, 'Noel Matthews' noel@... [ukmicrowaves] <ukmicrowaves@...> wrote:


I’m looking for a couple of WG11 (3.4GHz) to N type flanges, either to borrow for a few days (preferred) or buy.

Has anyone got anything they will part with?

73

Noel – G8GTZ



I don't have any. You can probably find formula on the web for making them, which would not be too hard if you have flanges. I just checked a couple of largest transitions I have, and it seems the centre conductor of the insert needs to be about half the height of the guide from the rear wall. Hence about 14 mm in a waveguide of that size (60.2488 x 28.4988 mm), and extend about 14 mm into the guide.

I think W1GHZ did some work on making ones own.

Ultimately an EM simulator would give you the best answer, but if you not too fussy about the return loss, making your own from some guidelines might be worth an attempt.

Dave


Sky Zone 2 dish

geoffrey pike
 

Does the measured 6mm spacing of the perfs in these dishes case problems using
it for 5.7 GHz
This is what i use and it only occured to me to measure the spacing after yesterdays
outing to the North Antrim hills.
thanks
Geoff
GI0GDP


Re: WG11 flanges

Noel G8GTZ
 

Should have said transitions not flanges J

 

From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: Monday, May 29, 2017 9:59 AM
To: ukmicrowaves@...
Subject: [ukmicrowaves] WG11 flanges

 

 

I’m looking for a couple of WG11 (3.4GHz) to N type flanges, either to borrow for a few days (preferred) or buy.

Has anyone got anything they will part with?

73

Noel – G8GTZ


WG11 flanges

Noel G8GTZ
 

I’m looking for a couple of WG11 (3.4GHz) to N type flanges, either to borrow for a few days (preferred) or buy.

Has anyone got anything they will part with?

73

Noel – G8GTZ


Re: Dishes available.

david.crowe2003@...
 

Hi All

Can I ask if the people that picked up the Advent 1.5m dish back in June last year from Devizes  could contact me so I can have a chat or put me in contact with them it would realy help me. You can contact me offline  david_s_crowe (at) hotmail.com.

73's
G4MVU
Dave


Re: New 122 and 241 GHz Distances Claim May 2017

John Lambo
 

I mean Tripod ;-)

Dutch  ;-)


73  John PA7JB


Op 27-5-2017 om 21:47 schreef John Lambo:

Gratulations John and Ian,
Very nice set up you have there !!!
I like your trypot
Keep up the good work......


73  John  PA7JB



Op 27-5-2017 om 11:29 schreef kits@... [ukmicrowaves]:
 

A few OPs may have become aware that G8KQW and myself G8ACE spent Sunday 21st May testing and succeeding in extending two way communication distances on 122 and 241 GHz. The two way UK distance claim is now  6.8Km.  I am most grateful to Ian G8KQW whom drove over to Winchester spending twelve hours of his time driving and testing to make a two way possible.  There is a lengthy supporting video on my YouTube channel of the testing,  search  UKG8ACE.   Same videos are also on my web page.  www.microwaves.dsl.pipex.com

I shall add information to the video as time permits including some details of the equipment etc.  

Note initially on both bands a 3.9Km path was tried and then with success at that distance a move was made by G8KQW to another location 6.8Km away.  In each instance G8ACE was operating from his home qth.

73 John G8ACE





Re: GB3SEE

g4uvz@...
 

Back again this morning ...just in time for the contest!


Re: New 122 and 241 GHz Distances Claim May 2017

John Lambo
 

Gratulations John and Ian,
Very nice set up you have there !!!
I like your trypot
Keep up the good work......


73  John  PA7JB



Op 27-5-2017 om 11:29 schreef kits@... [ukmicrowaves]:

 

A few OPs may have become aware that G8KQW and myself G8ACE spent Sunday 21st May testing and succeeding in extending two way communication distances on 122 and 241 GHz. The two way UK distance claim is now  6.8Km.  I am most grateful to Ian G8KQW whom drove over to Winchester spending twelve hours of his time driving and testing to make a two way possible.  There is a lengthy supporting video on my YouTube channel of the testing,  search  UKG8ACE.   Same videos are also on my web page.  www.microwaves.dsl.pipex.com

I shall add information to the video as time permits including some details of the equipment etc.  

Note initially on both bands a 3.9Km path was tried and then with success at that distance a move was made by G8KQW to another location 6.8Km away.  In each instance G8ACE was operating from his home qth.

73 John G8ACE




Re: Activity list for the 5.7GHz and 10GHz UK Microwave Group Contests tomorrow

Martyn G3UKV
 

Callsign: G3ZME/P
Locator: IO82QL (Brown Clee)
Bands: 5.7 and 10 GHz
Talkback: 144.175 MHz (preferred) and 'KST.   Mobile 07932 927887
73 Martyn G3UKV

On 27/05/2017 15:58, stewart.g0lgs@... [ukmicrowaves] wrote:
 


Callsign G0LGS/P Stewart (and 2E0MDJ/P Matt)
Locator IO81XW
Bands:
5GHz WBFM 2.5W 23dBi Panel
10GHz 1 W 40cm Dish
Talkback ON4KST,  07552 849233, 144.175



Re: Activity list for the 5.7GHz and 10GHz UK Microwave Group Contests tomorrow

Stewart Wilkinson
 


Callsign G0LGS/P Stewart (and 2E0MDJ/P Matt)
Locator IO81XW
Bands:
5GHz WBFM 2.5W 23dBi Panel
10GHz 1 W 40cm Dish
Talkback ON4KST,  07552 849233, 144.175


Re: Activity list for the 5.7GHz and 10GHz UK Microwave Group Contests tomorrow

Andy G4JNT
 

The missing callsign, fourth in that list located at IO90IV with 5.76GHz is me
G4JNT

Andy


On 27 May 2017 at 13:26, G3XDY g3xdy@... [ukmicrowaves] <ukmicrowaves@...> wrote:
 

Thanks for your inputs - here is the activity list for tomorrows events, good luck everybody:

Callsign G6TRM/P
Locator JO01QD
Band 10GHz 10Watts 0.8M dish
Talkback ON4KST,  07941447392 Callsign: G4JNT

Callsign: G4ASR
Locator: IO81MX
Bands:  10GHz  5W  0.5m procomm dish
Talkback: ON4KST, 144.175
Times: Various (grandchildren & 70MHz cumulative!)

Callsign: G1DFL/P (and Rob G1TYY/P)
Locator: IO91OQ (Lacey Green), roving to IO91MP (Christmas Common)
Bands:  10GHz 0.2W 60cm offset dish
Talkback: 144.175MHz, 07713 432632, KST
Times: 1.30pm to 4.30pm

Locator: IO90IV
Bands: 5.7GHz 30cm flat plate antenna
Talkback: 01489 787424, possibly ON4KST

Callsign: GW3TKH/P
Locator: IO81LS
Bands: 5.7GHz 10W 1m dish
             10GHz  10W 1m dish
Talkback: ON4KST, 144.175, 07762885015
Times: From about 0900 BST

Callsign: GW4HQX/P
Locator: IO81LS
Bands: 5.7GHz 15W 23dBi flat panel
             10GHz  200mW 40cm dish
Talkback: ON4KST, 144.175, 07762885015
Times: Various

Callsign:GI0GDP/P
Locator: IO74CR or BU
Bands:   5.7GHz 4W Sky Zone 2 dish (Xtal)
             10GHz  1W Sky Zone 2 dish (GPS)
Time: From about 11:00 clock time
Mobile 07817 177907

Callsign: G8GTZ/p
Locator: IO91xx
Bands: 10GHz  5W 60cm offset dish
Talkback: ON4KST, 144.175
Times: 2pm onwards

Call: M0DTS/P
Loc: IO94LI
Bands: 10GHz 8w/60cm
Talkback: 144.175, Maybe KST if it works.

Call: G4UVZ
Loc: IO80KX
Bands: 10GHz 6W to 80cm dish
Talkback:
144.175  and KST ...if I can remember how to work it!
Times: 11:15 local onwards

Callsign: GM0USI/P
Loc: IO76XA
Bands: 10GHz 9W to 85cm dish
Talkback: phone me on 07785744643 if you would like sked
Times: about 1200 - 1400

Callsign: G3XDY
Locator: JO02OB
Bands: 5.7GHz 15W 60cm dish
              10GHz  10W 60cm dish
Talkback: ON4KST, 144.175
Times: Various

73

John G3XDY


Virus-free. www.avast.com



Activity list for the 5.7GHz and 10GHz UK Microwave Group Contests tomorrow

John Quarmby
 

Thanks for your inputs - here is the activity list for tomorrows events, good luck everybody:

Callsign G6TRM/P
Locator JO01QD
Band 10GHz 10Watts 0.8M dish
Talkback ON4KST,  07941447392 Callsign: G4JNT

Callsign: G4ASR
Locator: IO81MX
Bands:  10GHz  5W  0.5m procomm dish
Talkback: ON4KST, 144.175
Times: Various (grandchildren & 70MHz cumulative!)

Callsign: G1DFL/P (and Rob G1TYY/P)
Locator: IO91OQ (Lacey Green), roving to IO91MP (Christmas Common)
Bands:  10GHz 0.2W 60cm offset dish
Talkback: 144.175MHz, 07713 432632, KST
Times: 1.30pm to 4.30pm

Locator: IO90IV
Bands: 5.7GHz 30cm flat plate antenna
Talkback: 01489 787424, possibly ON4KST

Callsign: GW3TKH/P
Locator: IO81LS
Bands: 5.7GHz 10W 1m dish
             10GHz  10W 1m dish
Talkback: ON4KST, 144.175, 07762885015
Times: From about 0900 BST

Callsign: GW4HQX/P
Locator: IO81LS
Bands: 5.7GHz 15W 23dBi flat panel
             10GHz  200mW 40cm dish
Talkback: ON4KST, 144.175, 07762885015
Times: Various

Callsign:GI0GDP/P
Locator: IO74CR or BU
Bands:   5.7GHz 4W Sky Zone 2 dish (Xtal)
             10GHz  1W Sky Zone 2 dish (GPS)
Time: From about 11:00 clock time
Mobile 07817 177907

Callsign: G8GTZ/p
Locator: IO91xx
Bands: 10GHz  5W 60cm offset dish
Talkback: ON4KST, 144.175
Times: 2pm onwards

Call: M0DTS/P
Loc: IO94LI
Bands: 10GHz 8w/60cm
Talkback: 144.175, Maybe KST if it works.

Call: G4UVZ
Loc: IO80KX
Bands: 10GHz 6W to 80cm dish
Talkback:
144.175  and KST ...if I can remember how to work it!
Times: 11:15 local onwards

Callsign: GM0USI/P
Loc: IO76XA
Bands: 10GHz 9W to 85cm dish
Talkback: phone me on 07785744643 if you would like sked
Times: about 1200 - 1400

Callsign: G3XDY
Locator: JO02OB
Bands: 5.7GHz 15W 60cm dish
              10GHz  10W 60cm dish
Talkback: ON4KST, 144.175
Times: Various

73

John G3XDY


Virus-free. www.avast.com


GB3FNM 5760.92MHz

Andy G4JNT
 

Does anyone know the latest status of GB3FNM?

Beaconspot is showing it as "MAY BE AN INTERMITTENT FAULT" with the last spot several months ago on 24 October.

'jnt