Date   

Re: OZ5N Auto PLL

geoffrey pike
 

Hi Kevin,
The pics are too big for attaching so please go to the files section under OZ5N folder
Hope they are of some use
Geoff
GI0GDP


Re: Measuring Noise Figure

Andy G4JNT
 

I did it once with boiling water and room temperature on what was supposed to be a low noise amp (144MHz) of the late 1980s era.  I saw  a genuine "fraction of a dB" but back then didn't have the means to measure mean noise power reliably or accurately, especially in a wide bandwidth.

Simplistically:
Assume a 1dB noise figure LNA with sufficient gain to overcome any following stages.
1dB is equivalent to a noise temp T of  75K   (  since NF = 10.LOG(T / 290 + 1)

So the delta noise power seen at the output of the system for input at 100C = 373K and  Room Temp 290K 
= :
10.LOG[ (373 + 75) / (290 + 75) ]  = 0.89dB

Which ought to be measurable with modern wide bandwidth SDRs.  It wasn't reliable using a diode on the output of an SSB Rx in 1988 !

Andy  G4JNT

On 19 July 2016 at 11:54, Richard Baker perwick@... [ukmicrowaves] <ukmicrowaves@...> wrote:
 

Any noise measurement you make with an open transmission line is going to be dependant on its length.

Rather than me try to explain the theory I suggest you try the following experiment.

Connect a good 50 ohm dummy load to your 432MHz or above receiver under test and note the noise level (reading 1). Now disconnect the dummy load and take a series of readings (readings 2) with different lengths of open transmission line attached. Easily done by adding adaptors or short lengths of coax. You should find reading 2 is dependant on the length of the open transmission line. Finally add a dummy load to the end of your adjustable length transmission line to confirm you get the same value as reading 1.
 
If you are looking for a minimum equipment noise estimate I suggest you put your dummy load in the deep freeze for a few hours and while still very cold connect it to your receiver and note the noise level. Now let it warm to room temperature and note the reading again. You are looking for a very small change in noise level and indeed you might need to heat your dummy load to about 100C to see an easy to read difference. This is the hot and cold dummy load method and it should be reasonably accurate as long as the impedance of your dummy load does not change much with temperature.
 
I would be interested in what readings people get.
 
Richard
GD8EXI




On 18/07/2016, 18:19, "richard@... [ukmicrowaves]" <ukmicrowaves@...> wrote:

 
 
 
   

"Thoroughly disagree"  Thanks for your reply Chris. I am not clear with which approach you thoroughly disagree with however.

a) the gain method of measuring noise figure
b) measuring without an input load
c) measuring with an input load; or possibly
d) Derek's approach.

73 Richard G3CWI
 
   




Re: Measuring Noise Figure

Richard GD8EXI
 

Any noise measurement you make with an open transmission line is going to be dependant on its length.

Rather than me try to explain the theory I suggest you try the following experiment.

Connect a good 50 ohm dummy load to your 432MHz or above receiver under test and note the noise level (reading 1). Now disconnect the dummy load and take a series of readings (readings 2) with different lengths of open transmission line attached. Easily done by adding adaptors or short lengths of coax. You should find reading 2 is dependant on the length of the open transmission line. Finally add a dummy load to the end of your adjustable length transmission line to confirm you get the same value as reading 1.
 
If you are looking for a minimum equipment noise estimate I suggest you put your dummy load in the deep freeze for a few hours and while still very cold connect it to your receiver and note the noise level. Now let it warm to room temperature and note the reading again. You are looking for a very small change in noise level and indeed you might need to heat your dummy load to about 100C to see an easy to read difference. This is the hot and cold dummy load method and it should be reasonably accurate as long as the impedance of your dummy load does not change much with temperature.
 
I would be interested in what readings people get.
 
Richard
GD8EXI




On 18/07/2016, 18:19, "richard@... [ukmicrowaves]" <ukmicrowaves@...> wrote:

 
 
 
   

"Thoroughly disagree"  Thanks for your reply Chris. I am not clear with which approach you thoroughly disagree with however.

a) the gain method of measuring noise figure
b) measuring without an input load
c) measuring with an input load; or possibly
d) Derek's approach.

73 Richard G3CWI
 
   



New file uploaded to ukmicrowaves

ukmicrowaves@...
 

Hello,


This email message is a notification to let you know that
a file has been uploaded to the Files area of the ukmicrowaves
group.


File : /OZ5N/P1010697.JPG
Uploaded by : gi0gdp <gi0gdp@yahoo.co.uk>
Description :


You can access this file at the URL:
https://groups.yahoo.com/neo/groups/ukmicrowaves/files/OZ5N/P1010697.JPG


To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398


Regards,


gi0gdp <gi0gdp@yahoo.co.uk>


New file uploaded to ukmicrowaves

ukmicrowaves@...
 

Hello,


This email message is a notification to let you know that
a file has been uploaded to the Files area of the ukmicrowaves
group.


File : /OZ5N/P1010696.JPG
Uploaded by : gi0gdp <gi0gdp@yahoo.co.uk>
Description :


You can access this file at the URL:
https://groups.yahoo.com/neo/groups/ukmicrowaves/files/OZ5N/P1010696.JPG


To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398


Regards,


gi0gdp <gi0gdp@yahoo.co.uk>


Re: F/GM0USI/P IN78/88 3cm next week

Alan
 

Ok..Ed,

I will see how it goes on Wednesday with the other stations..am sure l can certainly try another time up to Sunday when you might be able to make it...

73 Alan



Sent from my Samsung device


-------- Original message --------
From: "Edward Harland g3vpf@... [ukmicrowaves]"
Date: 19/07/2016 08:44 (GMT+01:00)
To: ukmicrowaves@..., ukmicrowaves@...
Subject: Re: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

Alan


Regrettably Weds is the only day this week I can't make, tied up in a meeting in Southampton all day. For info there was all the visual signs of a super-refraction duct out in the Channel this afternoon. Also, the weather will change overnight Tuesday into Wednesday to much cooler air so little chance of surface ducts after that.

Ed G3VPF


 

Yep you've picked a week of good weather Wednesday is good for me, have to be somewhere in the morning but should be done by lunch so will head straight over to lane end 

73 John


 

Hi there,

Have arrived in the Roscoff area and am staying for a week in St Pol de.Leon just to the south...wx looks extremely warm tomorrow so thinking Wednesday around 13-1500local...local time here is 1 hour ahead...
I can use my phone for calls and data so l can easily phone or attempt to get on KST...l will be using 10368.120...cw possible also
Kit is only around 1.75w to a flatflat panel antenna of around 20db...
Hopefully l haven't forgotten anything..
If Wednesday doesn't suit l may be able to make time on another occasion. .
Locator should be about IN88AQ but that may change if l can't get a parking space hi.
73 Alan F/GM0USI/P 07785744643




Sent from my Samsung device
-------- Original message --------
From: "Alan Dimmick dimmickalan@... [ukmicrowaves]"
Date: 18/07/2016 01:03 (GMT+01:00)
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

No probs Adrian,

Am.on the ferry as l write...l think tues or wed is looking possible but will post further details. .

73 Alan



Sent from my Samsung device


-------- Original message --------
From: "Adrian whatmore g4uvz@... [ukmicrowaves]"
Date: 17/07/2016 14:41 (GMT+00:00)
To: ukmicrowaves@...
Subject: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

I too am keen to work across from the south west from one of my sites near Taunton ..I think that you plan to work Edward VPF ..so could deploy at a similar time ..Happy for a timed sked if neccessary,,I too run the DGU but now with a 7 watt PA ,so we should have no problems
Adrian 07778 523 832   adrianwhatmore248@...


Re: Measuring Noise Figure

Chris Trask <christrask@...>
 

B


"Thoroughly disagree" Thanks for your reply Chris. I am not clear with which approach you thoroughly disagree with however.

a) the gain method of measuring noise figure
b) measuring without an input load
c) measuring with an input load; or possibly
d) Derek's approach.


73 Richard G3CWI

Chris

When the going gets weird, the weird turn pro
- Hunter S. Thompson


Re: OZ5N Auto PLL

Kevin Kerr <kkerr@...>
 

Is there any chance of pictures of how you installed it. I have a working G2 and am extremely nervous about attacking it with a solderong iron.

The picture on the website is a different transverter.

Kevin Kerr

M1BWS


On 18/07/2016 10:59, geoffrey pike gi0gdp@... [ukmicrowaves] wrote:
 
Back to DC matters at 10.368 GHz, i finally fitted my OZ5N auto pll and this is what happened.
Well it really didn't want to lock up at all, i changed the 82 p at the crystal to 56p. I gave everything some time to warm up and although
the blue LED flashed at 1 sec intervals it just wasn't for locking up.I adjusted the coil for a resting frequency about 200 Hz high and tried again and it locked up OK. I measured the control voltage at 1.04v and readjusted for 1.7v as i thought that this would be better and sure enough when i tried it all again the lock up was within 2 seconds.
with a soldering ir
I then put it all back together again and got my signal source fro 10.368200 GHz going and tuned in spot on 144.200 on the 290 and it just sits there rock steady T9. So that only leaves azimuth control of the dish as an unknown !.
regards
Geoff
GI0GDP
I measured the crystal frequency on the collector of the first tripler via a 22p cap


Re: Measuring Noise Figure

Chris Trask <christrask@...>
 

Yes. When I get home I'll locate a PDF document I wrote for doing it.


Hi Chris,

Your method sounds interesting - I'd like to try it.

Can you outline the calculations required, or point to a site or source that has the detail ?

Regards,

Martin - G8JNJ

Chris Trask
N7ZWY / WDX3HLB
Senior Member IEEE
http://www.home.earthlink.net/~christrask/


Re: Measuring Noise Figure

Martin - G8JNJ
 

Hi Chris,

Your method sounds interesting - I'd like to try it.

Can you outline the calculations required, or point to a site or source that has the detail ?

Regards,

Martin - G8JNJ

www.g8jnj.net
www.tc2m.info
http://websdr.suws.org.uk


Re: F/GM0USI/P IN78/88 3cm next week

Ed G3VPF
 

Alan

Regrettably Weds is the only day this week I can't make, tied up in a meeting in Southampton all day. For info there was all the visual signs of a super-refraction duct out in the Channel this afternoon. Also, the weather will change overnight Tuesday into Wednesday to much cooler air so little chance of surface ducts after that.

Ed G3VPF


On Mon, 18 Jul, 2016 at 16:33, 'g7jtt@...' g7jtt@... [ukmicrowaves]
wrote:
 

Yep you've picked a week of good weather Wednesday is good for me, have to be somewhere in the morning but should be done by lunch so will head straight over to lane end 

73 John


 

Hi there,

Have arrived in the Roscoff area and am staying for a week in St Pol de.Leon just to the south...wx looks extremely warm tomorrow so thinking Wednesday around 13-1500local...local time here is 1 hour ahead...
I can use my phone for calls and data so l can easily phone or attempt to get on KST...l will be using 10368.120...cw possible also
Kit is only around 1.75w to a flatflat panel antenna of around 20db...
Hopefully l haven't forgotten anything..
If Wednesday doesn't suit l may be able to make time on another occasion. .
Locator should be about IN88AQ but that may change if l can't get a parking space hi.
73 Alan F/GM0USI/P 07785744643




Sent from my Samsung device
-------- Original message --------
From: "Alan Dimmick dimmickalan@... [ukmicrowaves]"
Date: 18/07/2016 01:03 (GMT+01:00)
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

No probs Adrian,

Am.on the ferry as l write...l think tues or wed is looking possible but will post further details. .

73 Alan



Sent from my Samsung device


-------- Original message --------
From: "Adrian whatmore g4uvz@... [ukmicrowaves]"
Date: 17/07/2016 14:41 (GMT+00:00)
To: ukmicrowaves@...
Subject: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

I too am keen to work across from the south west from one of my sites near Taunton ..I think that you plan to work Edward VPF ..so could deploy at a similar time ..Happy for a timed sked if neccessary,,I too run the DGU but now with a 7 watt PA ,so we should have no problems
Adrian 07778 523 832   adrianwhatmore248@...


Re: Measuring Noise Figure

richard@...
 

"Thoroughly disagree"  Thanks for your reply Chris. I am not clear with which approach you thoroughly disagree with however.

a) the gain method of measuring noise figure
b) measuring without an input load
c) measuring with an input load; or possibly
d) Derek's approach.

73 Richard G3CWI


Re: Measuring Noise Figure

Chris Trask <christrask@...>
 

Thoroughly disagree. I use the 3dB method, which requires a 50-ohm termination, a 3-dB attenuation pad, a noise source, and a means for measuring output noise power (typically a spectrum analyzer). You first measure the amplifier output noise with the 50-ohm termination at the input. Then you add the 3-dB attenuator to the output and the noise source to the input. You adjust the noise source power until the two measurements are the same, then go through some calculations to determine the NF.


I watched a Youtube video recently about measuring noise figure using the measured gain of an amplifier
and a spectrum analyser. The thing that I found odd was that the video maker did not terminate the input
of the amplifier - he said it did not matter. I can think of two reasons why it might matter:

1) the input load resistor provides the base thermal noise level (I suppose it might not matter much if
the amplifier is very noisy)
2) some amplifiers are not entirely stable when un-terminated.

Would you agree?


Chris

When the going gets weird, the weird turn pro
- Hunter S. Thompson


432 and Above EME Newsletter for July 2016

rein0zn@...
 

Hello All,

The 432 MHz and Above EME Newsletter for July 2016 by K2UYH can be downloaded from:

http://www.nitehawk.com/rasmit/em70cm.html

-- Enjoy

73 Rein W6SZ


Re: Measuring Noise Figure

Derek Kozel <derek.kozel@...>
 

There are different approaches to measuring noise figure. I always use a y factor test and leave the noise source attached to the input of the amplifier/receiver. Powering on and off the noise source provides the change in stimulus to calculate the noise figure but keeps the termination as close as possible, including reducing thermal changes in the short term.

On Mon, Jul 18, 2016 at 7:09 AM, richard@... [ukmicrowaves] <ukmicrowaves@...> wrote:
 

Hi all


I watched a Youtube video recently about measuring noise figure using the measured gain of an amplifier and a spectrum analyser. The thing that I found odd was that the video maker did not terminate the input of the amplifier - he said it did not matter. I can think of two reasons why it might matter:


1) the input load resistor provides the base thermal noise level (I suppose it might not matter much if the amplifier is very noisy)

2) some amplifiers are not entirely stable when un-terminated.


Would you agree?


73 Richard G3CWI



Re: F/GM0USI/P IN78/88 3cm next week

John McCarthy
 

Yep you've picked a week of good weather Wednesday is good for me, have to be somewhere in the morning but should be done by lunch so will head straight over to lane end 
73 John


On Mon, 18 Jul, 2016 at 16:28, Alan Dimmick dimmickalan@... [ukmicrowaves]
wrote:
 

Hi there,

Have arrived in the Roscoff area and am staying for a week in St Pol de.Leon just to the south...wx looks extremely warm tomorrow so thinking Wednesday around 13-1500local...local time here is 1 hour ahead...
I can use my phone for calls and data so l can easily phone or attempt to get on KST...l will be using 10368.120...cw possible also
Kit is only around 1.75w to a flatflat panel antenna of around 20db...
Hopefully l haven't forgotten anything..
If Wednesday doesn't suit l may be able to make time on another occasion. .
Locator should be about IN88AQ but that may change if l can't get a parking space hi.
73 Alan F/GM0USI/P 07785744643




Sent from my Samsung device
-------- Original message --------
From: "Alan Dimmick dimmickalan@... [ukmicrowaves]" <ukmicrowaves@...>
Date: 18/07/2016 01:03 (GMT+01:00)
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

No probs Adrian,

Am.on the ferry as l write...l think tues or wed is looking possible but will post further details. .

73 Alan



Sent from my Samsung device


-------- Original message --------
From: "Adrian whatmore g4uvz@... [ukmicrowaves]"
Date: 17/07/2016 14:41 (GMT+00:00)
To: ukmicrowaves@...
Subject: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

I too am keen to work across from the south west from one of my sites near Taunton ..I think that you plan to work Edward VPF ..so could deploy at a similar time ..Happy for a timed sked if neccessary,,I too run the DGU but now with a 7 watt PA ,so we should have no problems
Adrian 07778 523 832   adrianwhatmore248@...


Re: F/GM0USI/P IN78/88 3cm next week

Alan
 

Hi there,

Have arrived in the Roscoff area and am staying for a week in St Pol de.Leon just to the south...wx looks extremely warm tomorrow so thinking Wednesday around 13-1500local...local time here is 1 hour ahead...
I can use my phone for calls and data so l can easily phone or attempt to get on KST...l will be using 10368.120...cw possible also
Kit is only around 1.75w to a flatflat panel antenna of around 20db...
Hopefully l haven't forgotten anything..
If Wednesday doesn't suit l may be able to make time on another occasion. .
Locator should be about IN88AQ but that may change if l can't get a parking space hi.
73 Alan F/GM0USI/P 07785744643




Sent from my Samsung device

-------- Original message --------
From: "Alan Dimmick dimmickalan@... [ukmicrowaves]"
Date: 18/07/2016 01:03 (GMT+01:00)
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

No probs Adrian,

Am.on the ferry as l write...l think tues or wed is looking possible but will post further details. .

73 Alan



Sent from my Samsung device


-------- Original message --------
From: "Adrian whatmore g4uvz@... [ukmicrowaves]"
Date: 17/07/2016 14:41 (GMT+00:00)
To: ukmicrowaves@...
Subject: [ukmicrowaves] Re: F/GM0USI/P IN78/88 3cm next week

 

I too am keen to work across from the south west from one of my sites near Taunton ..I think that you plan to work Edward VPF ..so could deploy at a similar time ..Happy for a timed sked if neccessary,,I too run the DGU but now with a 7 watt PA ,so we should have no problems
Adrian 07778 523 832   adrianwhatmore248@...


Re: Further Millimetric report Sunday 17th July

Roger Ray
 

John - That is a great achievement considering the high humidity.
That means there was some form of communication on Sunday, on all bands 24GHz and above.
Thats a first!!

Roger
G8CUB


Measuring Noise Figure

richard@...
 

Hi all


I watched a Youtube video recently about measuring noise figure using the measured gain of an amplifier and a spectrum analyser. The thing that I found odd was that the video maker did not terminate the input of the amplifier - he said it did not matter. I can think of two reasons why it might matter:


1) the input load resistor provides the base thermal noise level (I suppose it might not matter much if the amplifier is very noisy)

2) some amplifiers are not entirely stable when un-terminated.


Would you agree?


73 Richard G3CWI


Re: First UK QSO on the 122 GHz band

mjniman@...
 


Congrats on another mmWave first!

Whilst we have often not favoured the 122GHz band due to the Oxgyen resonance losses (similar to the 60 GHz band)  - all activity counts! - and like the exempt 60Ghz band is expected to see a growth in new chips and short range devices

73

 Murray G6JYB

PS Video/pics welcome of course!