Date   

Re: Ecoflex 15?

Mark GM4ISM
 

Using LDF4-50 at 10GHz is possible but not reliable. Its fine at 6cm  but at 3cm it can support waveguide modes and given the opportunity it will try.   If the run is very straight  with only very shallow bends you may get away with it but given that that is not always practical,  any bends may launch waveguide modes which  then don't couple back out and  dramatically increase the through loss.  Even FSJ4-50, quoted as having a max frequency of 10.0 GHz can go lossy with tight bends.  I have however used this feeder successfully  in the past( after I  took out a sharp bend which increased the loss by 15dB)

The largest easily obtained coaxial cable  that is  reliable at 10GHz is 3/8" or similar .  My LDF2-50 run is more lossy than LDF4-50 would be but is about as good as you can get without going to waveguide (which of course would be no good for a multiband feed)

My system uses FSJ1-50  around the rotator btw, I find the bigger solid outer feeders fracture too easily.

My total feeder loss is 4db at 10GHz but it works..  A head-amp on RX  would help,  I don't mind the loss on TX with 50W in the shack HI

No free lunches here,  if you do get LFD4-50 to  run on 10GHz without excess losses, it probably wont be stable it there is any  movement  in the run.   I don't recommend it.

Mark GM4ISM



On 19/02/2021 22:42, Raymond Brooks wrote:
I'm thinking of using 4 x FSJ1-50 superflex to loop around rotator as I have a quantity of reasonable lengths, this will also make it easy to ground the feeder at the top of the mast. Has anyone tried using LDF4-50 for 6cm & 3cm. I know its outside the published frequency range but I was hoping to use it on a quad band dish feed on the mast as I'm not able to mount the tranverters on the mast.



On 17 Feb 2021 19:51, "militaryoperator via groups.io" <Military1944@...> wrote:
Where's the best place to get a short length of Eco15, say 10ft, 3 to 4Mtrs?

I want to replace the LMR400 feeder I'm using now.

ebay has a German supplier, any in UK?

Ben.


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Re: Ecoflex 15?

Raymond Brooks
 

I'm thinking of using 4 x FSJ1-50 superflex to loop around rotator as I have a quantity of reasonable lengths, this will also make it easy to ground the feeder at the top of the mast. Has anyone tried using LDF4-50 for 6cm & 3cm. I know its outside the published frequency range but I was hoping to use it on a quad band dish feed on the mast as I'm not able to mount the tranverters on the mast.



On 17 Feb 2021 19:51, "militaryoperator via groups.io" <Military1944@...> wrote:
Where's the best place to get a short length of Eco15, say 10ft, 3 to 4Mtrs?

I want to replace the LMR400 feeder I'm using now.

ebay has a German supplier, any in UK?

Ben.


--
Raymond G8KPS


Re: GB3SCF clean propagation

John Lemay
 

John, Neil

 

I can confirm that ‘PKT is good-n-loud here on 10GHz. No doubt lousy conditions as usual.

 

Never heard ‘OSW here either, and likewise I took advantage of likely tropo and rain to take a good listen.

 

John G4ZTR

 

 

From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of John Fell
Sent: 19 February 2021 14:35
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] GB3SCF clean propagation

 

Ah!

Missed that OSW is orf air .

I have yet to detect it here even with some impressive Wet along the path .

 

Looking at the mapping of reports on BeaconSpot.UK , nobody else has seen it to the South of its location - unless anybody wants to fess up ?

It's not the ideal path but maybe we are in an antenna null ?

 

Any news on the RPE and Greenham Common 10GHz Beacons anyone ??

 

73

John

G0API

 

On Fri, 19 Feb 2021 at 14:28, Neil Smith G4DBN <neil@...> wrote:

My signal into Mow Cop across the Pennines was almost free of scintillation around 00:30 this morning.  The faint troposcatter blur on the waterfall that GB3KBQ was managing to create from 340 km away was spread out over 50 Hz or so.  Nothing seen at all from PKT at 240 km.  With OSW and CAM both off and no signal this way from Martlesham, it was all a bit quiet, no sign of EU, not even the old faithfuls DB0GHZ or PI7ALK.

Neil G4DBN

On 19/02/2021 14:15, John Fell wrote:

Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

 

73

John

G0API

 

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:

GB3SCF seems extraordinarily non-scattered today on the 70km path.   

The trace it so sharp you can make out frequency wobble from the GPSDO on it

 

 


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Re: GB3SCF clean propagation

John Fell
 

My reply was to avoid Bonging your email thingy with Beacon Keeper reports OM .

I do get QSB even at 21km LOS ....LOL  . Got a couple of dB enhancement on 24GHz during that cold dry spell recently and to think it will be 20 years this May since we put them on air - TF.

John
G0API 

On Fri, 19 Feb 2021 at 14:31, Andy G4JNT <andy.g4jnt@...> wrote:
You are LOS to them, John :-)
I'd be worried if it never was its usual self with you

Double diffraction path here, with the New Forest mid point, and a local hill 1km away.



On Fri, 19 Feb 2021 at 14:15, John Fell <john.g0api@...> wrote:
Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

73
John
G0API

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:
GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it


image.png


Re: GB3SCF clean propagation

John Fell
 

Ah!
Missed that OSW is orf air .
I have yet to detect it here even with some impressive Wet along the path .

Looking at the mapping of reports on BeaconSpot.UK , nobody else has seen it to the South of its location - unless anybody wants to fess up ?
It's not the ideal path but maybe we are in an antenna null ?

Any news on the RPE and Greenham Common 10GHz Beacons anyone ??

73
John
G0API

On Fri, 19 Feb 2021 at 14:28, Neil Smith G4DBN <neil@...> wrote:

My signal into Mow Cop across the Pennines was almost free of scintillation around 00:30 this morning.  The faint troposcatter blur on the waterfall that GB3KBQ was managing to create from 340 km away was spread out over 50 Hz or so.  Nothing seen at all from PKT at 240 km.  With OSW and CAM both off and no signal this way from Martlesham, it was all a bit quiet, no sign of EU, not even the old faithfuls DB0GHZ or PI7ALK.

Neil G4DBN

On 19/02/2021 14:15, John Fell wrote:
Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

73
John
G0API

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:
GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it



Re: GB3SCF clean propagation

Andy G4JNT
 

You are LOS to them, John :-)
I'd be worried if it never was its usual self with you

Double diffraction path here, with the New Forest mid point, and a local hill 1km away.



On Fri, 19 Feb 2021 at 14:15, John Fell <john.g0api@...> wrote:
Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

73
John
G0API

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:
GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it


image.png


Re: GB3SCF clean propagation

Neil Smith G4DBN
 

My signal into Mow Cop across the Pennines was almost free of scintillation around 00:30 this morning.  The faint troposcatter blur on the waterfall that GB3KBQ was managing to create from 340 km away was spread out over 50 Hz or so.  Nothing seen at all from PKT at 240 km.  With OSW and CAM both off and no signal this way from Martlesham, it was all a bit quiet, no sign of EU, not even the old faithfuls DB0GHZ or PI7ALK.

Neil G4DBN

On 19/02/2021 14:15, John Fell wrote:
Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

73
John
G0API

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:
GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it



Re: GB3SCF clean propagation

John Fell
 

Seems it's usual self here , all be it windy and damp ..... all other beacons at IO80UU59QP  normal too.

73
John
G0API

On Fri, 19 Feb 2021 at 13:54, Andy G4JNT <andy.g4jnt@...> wrote:
GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it


image.png


GB3SCF clean propagation

Andy G4JNT
 

GB3SCF seems extraordinarily non-scattered today on the 70km path.   
The trace it so sharp you can make out frequency wobble from the GPSDO on it


image.png


10 and 24GHz dish feeds

John Lemay
 

'Morning all

Just a very brief commercial interlude, to let you know that I now have in
stock dish feeds for 10 and 24GHz.

Please browse Microwave Dish Feeds at www.aerial-parts.co.uk.


Regards

John G4ZTR





--
This email has been checked for viruses by AVG.
https://www.avg.com


Re: 3cm receive only system

Martyn G3UKV
 

Hi Dave
The German Octagon (PLL version) was quite good without mods, but it needed 30-45 minutes to stabilise.
I have changed over to the 'Bullseye 10KHz' which claims 2 ppm TCXO stability. It certainly is far better than the Octagon, and after 2-3 minutes power applied, stayed within the QO-100 NB beacon frequency, and didn't need re-tuning on a typical SSB or CW signal. In fact, I had slightly more initial drift from the SDRplay (Mk 1) which is my IF (~739 MHz) receiver.
73 Martyn G3UKV

On 18/02/2021 21:48, Dave Brown wrote:
I want to set up a receive only 3cm system to monitor beacons etc.
 I understand that there are a few LNBs that use a crystal controlled LO and
some of these are being used (with mods) to receive QO-100. As this
application is 3cm receive only I believe I should be able to use the LNB,
mechanically unmodified?
 I have no real limitations as regards IF frequency as long as its below
2GHz . I'm looking for recommendations as to which of the few LNBs available
that fall in this category I should get. If I can get away with no LO mods
so much the better but happy to eventually use an external  frequency source
if I find stability inadequate. Had a trawl through earlier posts re QO-100
etc but no clear picture has emerged re which LNB might be best for this
application.
 73
 Dave, ZL3FJ
 Christchurch, NZ











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Re: 3cm receive only system

eightyelectric
 

They can also be used modified, but the drift due to temparature is more than I could live with.



Sent from my Galaxy


-------- Original message --------
From: "eightyelectric via groups.io" <Eightyelectric@...>
Date: 18/02/2021 22:10 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 3cm receive only system

I have modified several of these, and the 4 output versions, for use on q100, and 10.368 GHz.


https://www.ebay.co.uk/itm/Octagon-Twin-PLL-Satellite-LNB-OTLG-0-1dB-Technology-Sensitive-25-MHZ-Crystal-/202622912037?_trksid=p2349624.m46890.l49292


Paul G6UAJ


Sent from my Galaxy


-------- Original message --------
From: Dave Brown <2c39a@...>
Date: 18/02/2021 21:48 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 3cm receive only system

I want to set up a receive only 3cm system to monitor beacons etc.
I understand that there are a few LNBs that use a crystal controlled LO and
some of these are being used (with mods) to receive QO-100. As this
application is 3cm receive only I believe I should be able to use the LNB,
mechanically unmodified?
I have no real limitations as regards IF frequency as long as its below
2GHz . I'm looking for recommendations as to which of the few LNBs available
that fall in this category I should get. If I can get away with no LO mods
so much the better but happy to eventually use an external  frequency source
if I find stability inadequate. Had a trawl through earlier posts re QO-100
etc but no clear picture has emerged re which LNB might be best for this
application.
73
Dave, ZL3FJ
Christchurch, NZ










Re: 3cm receive only system

Colin G4EML
 

Dave,

 

The problem is that the supply of LNBs is very unpredictable. Even those with the same part number often have different insides.

 

The Octagon LNBS were at one time very popular but QO-100 has caused the supply of those to dry up.

 

Basically any PLL type LNB will probably do what you want but there is always an element of chance when ordering.  Feed it with 18 V via a Bias T and listen on 618 MHz with a SDR Dongle.

 

You can get away without modifying if you are happy to cope with quite a lot of drift.  The frequency can be expected to be off  by 100s of KHz at 10GHz with  temperature drift. But it is normally fairly slow so you can still receive beacons OK. If you have a strong beacon to act as a marker it is not too much of a problem to compensate for the drift but if you only have weak beacons then you may struggle to find them.

It is fairly easy to modify most LNBs to feed in an external high stability reference, once you do that they work very well.  I have had one on  my mast without a dish for some years now and I can often hear beacons by rain scatter.

 

Colin G4EML

 

 

 

 

From: Dave Brown
Sent: 18 February 2021 21:48
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 3cm receive only system

 

I want to set up a receive only 3cm system to monitor beacons etc.

I understand that there are a few LNBs that use a crystal controlled LO and

some of these are being used (with mods) to receive QO-100. As this

application is 3cm receive only I believe I should be able to use the LNB,

mechanically unmodified?

I have no real limitations as regards IF frequency as long as its below

2GHz . I'm looking for recommendations as to which of the few LNBs available

that fall in this category I should get. If I can get away with no LO mods

so much the better but happy to eventually use an external  frequency source

if I find stability inadequate. Had a trawl through earlier posts re QO-100

etc but no clear picture has emerged re which LNB might be best for this

application.

73

Dave, ZL3FJ

Christchurch, NZ

 

 

 

 

 

 

 

 

 


Re: 3cm receive only system

eightyelectric
 

I have modified several of these, and the 4 output versions, for use on q100, and 10.368 GHz.


https://www.ebay.co.uk/itm/Octagon-Twin-PLL-Satellite-LNB-OTLG-0-1dB-Technology-Sensitive-25-MHZ-Crystal-/202622912037?_trksid=p2349624.m46890.l49292


Paul G6UAJ


Sent from my Galaxy


-------- Original message --------
From: Dave Brown <2c39a@...>
Date: 18/02/2021 21:48 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 3cm receive only system

I want to set up a receive only 3cm system to monitor beacons etc.
I understand that there are a few LNBs that use a crystal controlled LO and
some of these are being used (with mods) to receive QO-100. As this
application is 3cm receive only I believe I should be able to use the LNB,
mechanically unmodified?
I have no real limitations as regards IF frequency as long as its below
2GHz . I'm looking for recommendations as to which of the few LNBs available
that fall in this category I should get. If I can get away with no LO mods
so much the better but happy to eventually use an external  frequency source
if I find stability inadequate. Had a trawl through earlier posts re QO-100
etc but no clear picture has emerged re which LNB might be best for this
application.
73
Dave, ZL3FJ
Christchurch, NZ










3cm receive only system

Dave Brown
 

I want to set up a receive only 3cm system to monitor beacons etc.
I understand that there are a few LNBs that use a crystal controlled LO and
some of these are being used (with mods) to receive QO-100. As this
application is 3cm receive only I believe I should be able to use the LNB,
mechanically unmodified?
I have no real limitations as regards IF frequency as long as its below
2GHz . I'm looking for recommendations as to which of the few LNBs available
that fall in this category I should get. If I can get away with no LO mods
so much the better but happy to eventually use an external frequency source
if I find stability inadequate. Had a trawl through earlier posts re QO-100
etc but no clear picture has emerged re which LNB might be best for this
application.
73
Dave, ZL3FJ
Christchurch, NZ


Re: A proper RAE again

Glyn M0XGT
 

Andrew,
Yes, you’re right – I was collecting the data from the RSGB pages for each licence and the new page actually gave specific details of what it wasn’t! The PDF does indeed say 75 questions in 2.5 hrs which is much more sensible.

Glyn M0XGT


Re: A proper RAE again

Andrew G8TZJ
 
Edited

With the proposal to add:
Direct to Full: 130 questions, 4.5-hour, fee £73.00.
Have I read that correctly? 4 hours 30 mins for an exam? I took the first RAE multiple choice exam in 1979. The exam was split into two both circa 1 hours each, completed in one evening exam. Even degree level exams don't exceed 3 hours!

Subsequent edit.

AH that's more like it, SEE the PDF;
The Direct to Full Level assessment consists of an examination comprising 75 questions lasting 2½ hours.



73 Andrew G8TZJ


Re: Q65 test 23cms tonight?

Alan Beard
 

It's 23on23 in a day or three.

Here in Sydney Australia, at 8pm local, any hope???
That's 09:00 UTC.

Alan VK2ZIW

On Thu, 18 Feb 2021 19:26:04 +0000, Conrad, PA5Y wrote
> GE chaps after try Q65 on 432 I would like to try on 1296 if anyone is available. I will be on KST.
>  
> 73
>  
> Conrad PA5Y

---------------------------------------------------
Alan VK2ZIW
Before the Big Bang, God, Sela.
OpenWebMail 2.53, nothing in the cloud.


Q65 test 23cms tonight?

Conrad, PA5Y
 

GE chaps after try Q65 on 432 I would like to try on 1296 if anyone is available. I will be on KST.

 

73

 

Conrad PA5Y


Re: Ecoflex 15?

Conrad, PA5Y
 

I am also quite sure that the Commscope equivalent would be just as good. Here SCF12-50 is the cheapest cable I can find. The spinner connectors are also cheap.

 

Look here:

 

https://awbroadcast.com/produkt/rfs-cellflex-scf12-50j-superflexible-kabel/

 

Of course Brexit has made purchasing from here or Germany most unattractive and probably Arjan the proprietor of AW broadcast will not ship to the UK. But at these prices I will not use anything else.

 

73

 

Conrad PA5Y

 

PS drop G4LOH an email he has a very nice way of doing things and it seems super reliable.

 

 

 

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Dave G8KHU via groups.io
Sent: 18 February 2021 18:34
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Ecoflex 15?

 

Thank you Conrad :)

I'm hoping to get a decent antenna setup erected this year and will try using SCF12-50 for the loops
73
Dave

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