Date   

Re: 24GHz, 47GHz, and 76-248GHz Contests next weekend, 21st July

Martyn G3UKV
 

Hi Peter, Keith, Chris, Roger et al
Been studying potential paths re 24 GHz.
So....
Start at Brown Clee (IO82QL84), around 0930 (UTC). Path to JO01EP maybe ????(with lift!) + IO81LS, IO93FB, IO93AD likely
Rove to Little Wenlock area (IO82RQ60). Paths to IO81LS, IO93AD, IO93AF08 maybe. Middle of day.
Rove to Redhill or New Works (IO82TQ16, IO82SQ01). Later in afternoon.

Lots of room for new paths there, and lots of "....perhaps...". Any other suggestions ?
Trust the microwave group pick up the diesel fuel bill for participants ? (just to see who reads this...!)
Any one else other than previously declared coming out ?  The more the merrier;
73 Martyn (G3UKV/P on this occasion - rest of TDARS group gone AWOL)

On 17/07/2013 13:12, Peter Day wrote:
 


24GHz Sunday 21st July:

G3PHO/P: 24GHz only. 2watts to 60cm offset dish. Talkback:
144.175MHz ssb ...NO KST.

Roving around the Peak District: 10.00BST to
approx 11.30: Alport Height. IO93FB44
12:30BST-14:30: Merryton Low Triangle IO93AD
15:00BST - ? : Possibly Cat & Fiddle near Buxton or other
location on demand.

It would be great if some of the southern stations
travelled to a location suitable for working us northerners ... say
within 160km or so of
Alport and Merryton ... locations like Malvern
Hills, Cotswolds, Chilterns, Coombe Gibbett, Therfield, etc.

Years ago there were several of you who had a
sense of adventure and tried to do new paths etc on these bands. Today
they seem happy to reinvent the wheel and work the
same old tried and tested ones month after month ... boring! :-)

... and don't tell me you're all too old to make
the trip ... I'm older than all of you!

73

Peter G3PHO

"Have rig... will travel"



24G contest tomorrow

g4bao
 

Sorry mmwavers but 3 days of g100rsgb with camb-hams has used up all my xyl points this week so I won't be active after all. Other things to do on Sunday.
73
John


Re: CCX 3cms

Graham G3VKV
 

GB3CCX is back to full strength here now the temperature is lower. Graham G3VKV


Blade RF

Keith Le Boutillier <keithl@...>
 

 

Hi Group

 

I keep looking at the RF bade unit at http://www.nuand.com/blog/shop/ Out of the box the bladeRF can tune from 300MHz to 3.8GHz without the need for extra boards and has current open source drivers.

 

Has anybody looked to see if it’s of any use in the field of microwaves or as a transverter driver I can’t help thinking that this might end up being a winter project for me to play with.

 

73 Keith GU6EFB


Re: G100RSGB -underwhelmed with uWave QSOS

G0DJA <dave@...>
 

I took a listen yesterday when it was reported that GB100RSGB was on 1296.210MHz, but didn't hear anything.

10GHz is not operational here at the moment but I might rig up a receive system for a cross band 3cm/23cm contact.

Dave (G0DJA)

--- In ukmicrowaves@yahoogroups.com, g4bao <john@...> wrote:

Give me something positive to report in GHz bands. Email me direct for
skeds. Note we only have takeoff N to W on 3cms, but 23cms all round.

73
John


Re: 1st 9H <--> IT9 24Ghz qso

Mansueto Grech <mansueto.grech@...>
 

Hi All Again,
In the excitement and given the time the e-mail was written, mistakenly I wrote johnny's call sign as IT9ARO which should have been IW9ARO.  Sorry for the mistake.

The mistake has been corrected in the Text below.
My apologies for the mistake.

73's
Mans. 9H1GB

On 20 July 2013 00:40, Mansueto Grech <mansueto.grech@...> wrote:
Hi All,
Please to inform your that today July 19th 2013 the first ever QSO ON 24Ghz was made between 9H and IT9

At 17:21 GMT IW9ARO (Johnny) heard my (9H1GB) signal on 24.048200GHz+/- Immediately I switch to USB and the QSO was completed  with  a 51 52 exchange of reports.
two other friends were with me Joe 9H1VW and Joe 9H1CG completed the QSO at 17:47 53 53 report and 17:48  with 58 59 report respectively After which I call Johnny again at exchanged a a 58 59 report.

Although we were all ecstatic with the contact made, a distance of 206km QSO from JM7EV to JM77LQ (mt Etna). we were also  very please to have help a new radio amateur, still waiting for his call, Trevor to made the 24 and 10GHz as his first ever QSO, NOT A BAD WAY TO START.

Johnny was using  18dbm (70mw) into a 45cm dish and I was using 23dbm (200mw) after the filter into a 60cms dish.
I am hoping to make links to audio file for these QSO soon
We are planning new test and mods to our system in the hope to improve the performance.
Both Johnny and myself also took our 3cm equipment with us and QSO were also made in this band
73's all
Mans. 9H1GB



Re: Agilent 346A and N9069A reading high?

Conrad Farlow <conrad@...>
 

Good points made by all and to mitigate against it I have used narrower bandwidths. I makes very little difference but it is still worth noting so thankyou for that.  Basically the N9069A allows you to use any bandwidth that the EXA series of instruments can use, i.e very narrow indeed. I went down to 100kHz and yes I did calibrate at this bandwidth.

I think that there may be several issues.

  1. Sheffield city centre is full of pagers - hence I can't get a decent stable cal - I am doing this at work.
  2. The HA8ET preamp is not particularly well screened, it has loose fitting lids - this could be quite easily improved
  3. There are stability issues
  4. The device is suspect?

I do have a screened enclosure big enough to do the measurements in, it's not a chamber but I can get access to one in Essex next time I visit G8CUB's splendid establishment.

I will investigate this further most probably after my much needed holiday, the first for 4 years! I will be on an island in the I8 region.

Thanks for the advice from all, it's nice to have the kit :)

73

Conrad G0RUZ



John Makes a good point - NF meters can typically measure in bandwidths of several MHz and are assuming the noise figure, gain and match is constant across this bandwidth.

When you design a preamp for VHF it is normally a good idea to make it narrow band, especially in the UK where we have very strong pager signals either side of 144MHz. To a DXer, there is nothing of importance outside the 144-145MHz range and a preamp may have a 3dB bandwidth of 2MHz or less to cover this range plus a bit. What this means depends on the filter shape and the NF meter bandwidth, but its quite possible to be missing nearly half the noise due to the filter. 

As John says this will mean the ENR calibration won't be right so the difference between noise on and off will be lower than expected resulting in a higher recorded noise figure. You can fix this with a filter which is difficult, or by doing the maths if you know the relative bandwidths, which may be easier.

The negative noise figure issues is probably just noise. If you expect to get better than 0.1dB accuracy after calibration you will need to be very careful, do a lot of integrating and keep everything at a constant temperature and do it all in a screened room. You should see a mean value of zero. The fact it is reading -0.1dB consistently could just be the instrument needs recalibrating, or maybe you have not got the settings right for temperature, or indicate external noise is getting into it from local RF sources and disturbing the calibration. If you are doing this at home I would go with the QRM. Since they installed a mobile phone mast at RAL near the RF lab, we haven't been able to measure VHF/UHF noise figures accurately in the RF lab.

Mike

--- In ukmicrowaves@..., G3XDY  wrote:
Hi Conrad

I have also seen abnormally high NF readings on an example of the HA8ET 
preamp. This preamp includes narrow band filtering, and it could be that 
the noise bandwidth of the preamp is narrower than the Agilent test set 
bandwidth. I recollect that you might be able to configure the Agilent 
box for a narrower measurement bandwidth, but I don't have the manual to 
check. The 8970A will suffer from the same problem and is not 
configurable, the only way to test such preamps with the 8970 series 
boxes is to build a low loss narrow band 144MHz filter, then calibrate 
the instrument with the filter in circuit and then test the preamp via 
the filter (bear in mind that the filter won't look like a flat 50 ohm 
source so there will be errors due to changes in the impedance seen by 
the preamp input unless you include an isolator after the filter).

73

John G3XDY


On 18/07/2013 13:44, Conrad Farlow wrote:
I have access to an Agilent 346A head with an N9069A noise figure
measurement application running on an EXA series spectrum analyser. It
seems to have number of issues.

1. After calibration the noise figure and gain are never truly zero, the
noise figure normally reads -0.1 or similar and the gain will be -0.15
or thereabouts, these are just typical figures.

2.When I measure noise figure I see good results on the gain but the
noise figure seems high. For instance my HA8ET Extra 2 LNA reads about
1.4dB whereas I am pretty sure that it is much better than this.

I have Tcold set to the temperature on the surface of the device as
measured by a thermocouple.  I have used some loss compensation before
the device, I have generously allowed 0.1 dB for a high quality
female-female N type.

Does anyone have any advice as to what is going wrong? I do have an 8970
that I could use for a reference check but it hasn't been switched on
for a while, shocking I know.......

Bit puzzled..

      



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1st 9H <--> IT9 24Ghz qso

Mansueto Grech <mansueto.grech@...>
 

Hi All,
Please to inform your that today July 19th 2013 the first ever QSO ON 24Ghz was made between 9H and IT9

At 17:21 GMT IT9ARO (Johnny) heard my (9H1GB) signal on 24.048200GHz+/- Immediately I switch to USB and the QSO was completed  with  a 51 52 exchange of reports.
two other friends were with me Joe 9H1VW and Joe 9H1CG completed the QSO at 17:47 53 53 report and 17:48  with 58 59 report respectively After which I call Johnny again at exchanged a a 58 59 report.

Although we were all ecstatic with the contact made, a distance of 206km QSO from JM7EV to JM77LQ (mt Etna). we were also  very please to have help a new radio amateur, still waiting for his call, Trevor to made the 24 and 10GHz as his first ever QSO, NOT A BAD WAY TO START.

Johnny was using  18dbm (70mw) into a 45cm dish and I was using 23dbm (200mw) after the filter into a 60cms dish.
I am hoping to make links to audio file for these QSO soon
We are planning new test and mods to our system in the hope to improve the performance.
Both Johnny and myself also took our 3cm equipment with us and QSO were also made in this band
73's all
Mans. 9H1GB


Re: [Moon] [Moon-Net] Agilent 346A and N9069A reading high?

Graham D <graham.d@...>
 

On 19/07/2013 16:10, Conrad Farlow wrote:
 

Its hooting you were right. I removed the noise head and put a load on
it and I can see a descrete frequency that has an 8dB noise figure. This
will be the frequency at which it's oscillating.

Glad you found it Conrad.

if its an ATF then it'll most likely be in the 5 to 6 GHz region.

(the narrow filter will not be helping it because the out of band match will be appalling from everywhere to everywhere else)

and I forgot....if anyone thinks they are going to **consistantly** measure differences of .01 and .03 on anything made by Agilent/HP then it's time to call the men in the white coats.

These things are Production line instruments not Research instruments.

Graham


Re: [Moon] [Moon-Net] Agilent 346A and N9069A reading high?

Conrad Farlow <conrad@...>
 

Ooops should have gone to Graham sorry.

__________________________________________________

73

Conrad G0RUZ IO93FR


North Wakefield Radio Club

__________________________________________________

On 19/07/2013 14:10, Conrad Farlow wrote:
Its hooting you were right. I removed the noise head and put a load on
it and I can see a descrete frequency that has an 8dB noise figure. This
will be the frequency at which it's oscillating.

Do you have anything with a known NF that I can check as a reference.
I'll send it straight back to you.

__________________________________________________

73

Conrad G0RUZ IO93FR


North Wakefield Radio Club

__________________________________________________
On 19/07/2013 06:38, Graham D wrote:
2.When I measure noise figure I see good results on the gain but the
noise figure seems high. For instance my HA8ET Extra 2 LNA reads about
1.4dB whereas I am pretty sure that it is much better than this.
it's all a lot simpler than long convoluted theories....

the pre amp is oscillating

Graham 'MBI 'VHX



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Re: [Moon] [Moon-Net] Agilent 346A and N9069A reading high?

Conrad Farlow <conrad@...>
 

Its hooting you were right. I removed the noise head and put a load on it and I can see a descrete frequency that has an 8dB noise figure. This will be the frequency at which it's oscillating.

Do you have anything with a known NF that I can check as a reference. I'll send it straight back to you.

__________________________________________________

73

Conrad G0RUZ IO93FR


North Wakefield Radio Club

__________________________________________________

On 19/07/2013 06:38, Graham D wrote:
2.When I measure noise figure I see good results on the gain but the
noise figure seems high. For instance my HA8ET Extra 2 LNA reads about
1.4dB whereas I am pretty sure that it is much better than this.
it's all a lot simpler than long convoluted theories....

the pre amp is oscillating

Graham 'MBI 'VHX



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OFCOM - DRAFT RESPONSE FOR COMMENT

g6jyb <mjniman@...>
 

Thanks for all inputs so far

THE RSGB DRAFT REPOSNSE IS NOW ONLINE

Web page:
http://rsgb.org/main/operating/band-plans/microwaves/spectrum-release/

Short Link:
http://rsgb.org/main/files/2013/07/draft-response-v2.pdf

This may be used for your own ideas as well as for comments back to me on substance and typos

Please note there are items in this draft that so far may have been missed in other considerations inc on:-

a) the answer to Q1,
b) impact on European amateurs, if the bands are lost
c) the 2300-2310 option offer
d) a wider range of other measures that would complement the technical support offer that I am glad UKuG and BATC are up for

As with other efforts I would be glad of formal endorsements by UKuG, BATC and Amsat-UK who have contributed to various aspects

regards

Murray

Based on feedback we will update it add boilerplate etc prior to teh 5pm Monday deadline

--- In ukmicrowaves@yahoogroups.com, "Michael Scott" <g3lyp@...> wrote:

Hi Murray and others.

Folowing the useful discussion session at Finningley, I have just submitted my response online.

73, Mike, G3LYP
----- Original Message -----
From: g6jyb
To: ukmicrowaves@yahoogroups.com
Sent: Thursday, July 18, 2013 11:35 AM
Subject: [ukmicrowaves] Re: Ofcom deadline approaching (next Monday July 22nd)




For those who dont like the online form, a MS-Word Template is on the UKuG home page if you look at the latest update there

Murray

--- In ukmicrowaves@yahoogroups.com, "g8gtz" <noel@> wrote:
>
> All,
>
> Just a reminder that the closing date for the Ofcom 2.3 Ghz consultation process is approaching.
>
> I believe that everyone, whether active on 2.3 Ghz or not should respond, as we need to show Ofcom that we value the spectrum we have access to.
>
> If they do not see a large response, they will be more inclined when considering the future of other bands, such as 10 GHz, to take the approach of the authorities in Sweden and Australia and just remove our access to bands without consultation.
>
> In order to encourage responses from the ATV community, who are particularly affected by the proposed changes, I have posted my own proposed responses on the BATC forum at http://www.batc.org.uk/forum/viewtopic.php?f=2&t=3176&start=10
>
> Chris GW4DGU has also published his responses in the latest issue of Scatterpoint.
>
> Thanks to the good work by Murray and others we do have a good relationship with our regulator in the UK and this is the opportunity for us all to show them how much we value the spectrum we have access to.
>
> 73
>
> Noel - G8GTZ
>


Re: G100RSGB -underwhelmed with uWave QSOS

Robert Price <g8dtf@...>
 

Sorry John taken the transverter and antenna off the mast so I could paint my shack whilst the weather was good.

73

Bob
G8DTF



From: g4bao
To: "Ukmicrowaves (ukmicrowaves@...)" <ukmicrowaves@...>
Sent: Friday, 19 July 2013, 11:54
Subject: [ukmicrowaves] G100RSGB -underwhelmed with uWave QSOS

 
Come on UKmicrowavers! G100RSGB has been ready with 23 and 3cms gear and so far, above 1GHz we have had two 3cms and 6 23cms QSOs. Almost no UK 3cms stations logged in to KST yesterday, compared to tens in France, and no sked requests via the 6 and 2m stations.
Give me something positive to report in GHz bands. Email me direct for skeds. Note we only have takeoff N to W on 3cms, but 23cms all round.
73
John



Re: G100RSGB -underwhelmed with uWave QSOS

Ralph
 

Hello John,
 
I have had virtually no conditions on any band 2m and up for past two days.
 
If your on after 7 or 8 in the evening I will gladly try but the bands are
as flat as a pancake here during the day.
 
I have been in the shack around 0500-0600z for the past week
but since last week-end It really was a waste of good sleep
73
Ralph

----- Original Message -----
From: g4bao
Sent: Friday, July 19, 2013 11:54 AM
Subject: [ukmicrowaves] G100RSGB -underwhelmed with uWave QSOS

 

Come on UKmicrowavers! G100RSGB has been ready with 23 and 3cms gear and so far, above 1GHz we have had two 3cms and 6 23cms QSOs. Almost no UK 3cms stations logged in to KST yesterday, compared to tens in France, and no sked requests via the 6 and 2m stations.
Give me something positive to report in GHz bands. Email me direct for skeds. Note we only have takeoff N to W on 3cms, but 23cms all round.

73
John

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2013.0.3349 / Virus Database: 3204/6502 - Release Date: 07/18/13


Re: Ofcom deadline approaching (next Monday July 22nd)

Michael Scott
 

Hi Murray and others.
 
Folowing the useful discussion session at Finningley, I have just submitted my response online.
 
73, Mike, G3LYP

----- Original Message -----
From: g6jyb
Sent: Thursday, July 18, 2013 11:35 AM
Subject: [ukmicrowaves] Re: Ofcom deadline approaching (next Monday July 22nd)

 


For those who dont like the online form, a MS-Word Template is on the UKuG home page if you look at the latest update there

Murray

--- In ukmicrowaves@..., "g8gtz" wrote:
>
> All,
>
> Just a reminder that the closing date for the Ofcom 2.3 Ghz consultation process is approaching.
>
> I believe that everyone, whether active on 2.3 Ghz or not should respond, as we need to show Ofcom that we value the spectrum we have access to.
>
> If they do not see a large response, they will be more inclined when considering the future of other bands, such as 10 GHz, to take the approach of the authorities in Sweden and Australia and just remove our access to bands without consultation.
>
> In order to encourage responses from the ATV community, who are particularly affected by the proposed changes, I have posted my own proposed responses on the BATC forum at http://www.batc.org.uk/forum/viewtopic.php?f=2&t=3176&start=10
>
> Chris GW4DGU has also published his responses in the latest issue of Scatterpoint.
>
> Thanks to the good work by Murray and others we do have a good relationship with our regulator in the UK and this is the opportunity for us all to show them how much we value the spectrum we have access to.
>
> 73
>
> Noel - G8GTZ
>


Re: CCX 3cms - on or off - not CW

John Fell
 

I also have not seen CCX for several weeks , but it needs some rain along the path to pop up above noise and its been 30C a lot and very dry for July so far .Prepare for flooding .........

73
John 
G0API


On Fri, Jul 19, 2013 at 12:04 PM, g3vkv <g3vkv@...> wrote:
 

Hi John, that one has been fixed some time ago, the GB3UK repeater antenna has been moved to another corner of the mast, will see if I can find out more info - perhaps it doesn't like the heat, CCX is way down in strength here, maybe the PA has gone, it would only take a few milliwatts to be the strength it is here at 4km. 73 Graham

--- In ukmicrowaves@..., "usuallyqrt" wrote:
>
> CCX 3cms had a fault some time back where it would go off if the 70cm repeater was on. Easy to check if the 70cms is on and the beacon is off thats it. Or fire up the repeater and see if CCX goes off. Not seen anything reported that its been fixed. I dont hear CCX at ohm so unable to check this out myself. 73s John.
>



Re: CCX 3cms - on or off - not CW

Graham G3VKV
 

Hi John, that one has been fixed some time ago, the GB3UK repeater antenna has been moved to another corner of the mast, will see if I can find out more info - perhaps it doesn't like the heat, CCX is way down in strength here, maybe the PA has gone, it would only take a few milliwatts to be the strength it is here at 4km. 73 Graham

--- In ukmicrowaves@yahoogroups.com, "usuallyqrt" <usuallyqrt@...> wrote:

CCX 3cms had a fault some time back where it would go off if the 70cm repeater was on. Easy to check if the 70cms is on and the beacon is off thats it. Or fire up the repeater and see if CCX goes off. Not seen anything reported that its been fixed. I dont hear CCX at ohm so unable to check this out myself. 73s John.


G100RSGB -underwhelmed with uWave QSOS

g4bao
 

Come on UKmicrowavers! G100RSGB has been ready with 23 and 3cms gear and so far, above 1GHz we have had two 3cms and 6 23cms QSOs. Almost no UK 3cms stations logged in to KST yesterday, compared to tens in France, and no sked requests via the 6 and 2m stations.
Give me something positive to report in GHz bands. Email me direct for skeds. Note we only have takeoff N to W on 3cms, but 23cms all round.

73
John


Re: Agilent 346A and N9069A reading high?

Mike Willis
 

John Makes a good point - NF meters can typically measure in bandwidths of several MHz and are assuming the noise figure, gain and match is constant across this bandwidth.

When you design a preamp for VHF it is normally a good idea to make it narrow band, especially in the UK where we have very strong pager signals either side of 144MHz. To a DXer, there is nothing of importance outside the 144-145MHz range and a preamp may have a 3dB bandwidth of 2MHz or less to cover this range plus a bit. What this means depends on the filter shape and the NF meter bandwidth, but its quite possible to be missing nearly half the noise due to the filter.

As John says this will mean the ENR calibration won't be right so the difference between noise on and off will be lower than expected resulting in a higher recorded noise figure. You can fix this with a filter which is difficult, or by doing the maths if you know the relative bandwidths, which may be easier.

The negative noise figure issues is probably just noise. If you expect to get better than 0.1dB accuracy after calibration you will need to be very careful, do a lot of integrating and keep everything at a constant temperature and do it all in a screened room. You should see a mean value of zero. The fact it is reading -0.1dB consistently could just be the instrument needs recalibrating, or maybe you have not got the settings right for temperature, or indicate external noise is getting into it from local RF sources and disturbing the calibration. If you are doing this at home I would go with the QRM. Since they installed a mobile phone mast at RAL near the RF lab, we haven't been able to measure VHF/UHF noise figures accurately in the RF lab.

Mike

--- In ukmicrowaves@yahoogroups.com, G3XDY <g3xdy@...> wrote:

Hi Conrad

I have also seen abnormally high NF readings on an example of the HA8ET
preamp. This preamp includes narrow band filtering, and it could be that
the noise bandwidth of the preamp is narrower than the Agilent test set
bandwidth. I recollect that you might be able to configure the Agilent
box for a narrower measurement bandwidth, but I don't have the manual to
check. The 8970A will suffer from the same problem and is not
configurable, the only way to test such preamps with the 8970 series
boxes is to build a low loss narrow band 144MHz filter, then calibrate
the instrument with the filter in circuit and then test the preamp via
the filter (bear in mind that the filter won't look like a flat 50 ohm
source so there will be errors due to changes in the impedance seen by
the preamp input unless you include an isolator after the filter).

73

John G3XDY


On 18/07/2013 13:44, Conrad Farlow wrote:
I have access to an Agilent 346A head with an N9069A noise figure
measurement application running on an EXA series spectrum analyser. It
seems to have number of issues.

1. After calibration the noise figure and gain are never truly zero, the
noise figure normally reads -0.1 or similar and the gain will be -0.15
or thereabouts, these are just typical figures.

2.When I measure noise figure I see good results on the gain but the
noise figure seems high. For instance my HA8ET Extra 2 LNA reads about
1.4dB whereas I am pretty sure that it is much better than this.

I have Tcold set to the temperature on the surface of the device as
measured by a thermocouple. I have used some loss compensation before
the device, I have generously allowed 0.1 dB for a high quality
female-female N type.

Does anyone have any advice as to what is going wrong? I do have an 8970
that I could use for a reference check but it hasn't been switched on
for a while, shocking I know.......

Bit puzzled..


Re: Agilent 346A and N9069A reading high?

John Quarmby
 

Hi Conrad

I have also seen abnormally high NF readings on an example of the HA8ET preamp. This preamp includes narrow band filtering, and it could be that the noise bandwidth of the preamp is narrower than the Agilent test set bandwidth. I recollect that you might be able to configure the Agilent box for a narrower measurement bandwidth, but I don't have the manual to check. The 8970A will suffer from the same problem and is not configurable, the only way to test such preamps with the 8970 series boxes is to build a low loss narrow band 144MHz filter, then calibrate the instrument with the filter in circuit and then test the preamp via the filter (bear in mind that the filter won't look like a flat 50 ohm source so there will be errors due to changes in the impedance seen by the preamp input unless you include an isolator after the filter).

73

John G3XDY

On 18/07/2013 13:44, Conrad Farlow wrote:
I have access to an Agilent 346A head with an N9069A noise figure
measurement application running on an EXA series spectrum analyser. It
seems to have number of issues.

1. After calibration the noise figure and gain are never truly zero, the
noise figure normally reads -0.1 or similar and the gain will be -0.15
or thereabouts, these are just typical figures.

2.When I measure noise figure I see good results on the gain but the
noise figure seems high. For instance my HA8ET Extra 2 LNA reads about
1.4dB whereas I am pretty sure that it is much better than this.

I have Tcold set to the temperature on the surface of the device as
measured by a thermocouple. I have used some loss compensation before
the device, I have generously allowed 0.1 dB for a high quality
female-female N type.

Does anyone have any advice as to what is going wrong? I do have an 8970
that I could use for a reference check but it hasn't been switched on
for a while, shocking I know.......

Bit puzzled..