Date   

Re: Heather Hall

Peter Day <microwaves@...>
 

Eddie G0EHV wrote:

Hello Peter,
You're all Southerners to me!
Regards,
Eddie
(On a very sunny Tyneside)
Away hinny! Way aye lad..


rf hamdesgn 1.9m dish

John Randall <m0els@...>
 

Has anyone successfully recovered these dishes with a finer mesh, to
enable 10ghz to be used and what mesh diamter.

Thanks
John


Re: Heather Hall

kenneth ferguson <ken_ferguson@...>
 

HEY I live up ere int  north it be noys an hille wid sum gud seanry ewe suthen folk sud cum fer a visit an sea what ewe bea misin 8>

ken

========================================
Message Received: Apr 19 2006, 04:48 PM
From: "Eddie G0EHV"
To: ukmicrowaves@...
Cc:
Subject: Re: [ukmicrowaves] Heather Hall


----- Original Message -----
From: "Peter Day"
To:
Sent: Tuesday, April 18, 2006 11:18 PM
Subject: Re: [ukmicrowaves] Heather Hall


> Ian Lamb wrote:
>> Andy, you wouldn't want to live up t'north would you????
>>
>>
>> Ian Lamb - G8KQW
>
>
> Nowt wrong wi' t'North tha naws.. Ah wuz born up 'ere o'coors.
>
> Peter, G3PHO
>

Hello Peter,
You're all Southerners to me!
Regards,
Eddie
(On a very sunny Tyneside)




Yahoo! Groups Links

<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ukmicrowaves/

<*> To unsubscribe from this group, send an email to:
ukmicrowaves-unsubscribe@...

<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/






ken ferguson
G0HYP IO84FN


Re: Heather Hall

kenneth ferguson <ken_ferguson@...>
 

HEY I live up ere int  north it be noys an hille wid sum gud seanry ewe suthen folk sud cum fer a visit an sea what ewe bea misin 8>

ken

========================================
Message Received: Apr 19 2006, 04:48 PM
From: "Eddie G0EHV"
To: ukmicrowaves@...
Cc:
Subject: Re: [ukmicrowaves] Heather Hall


----- Original Message -----
From: "Peter Day"
To:
Sent: Tuesday, April 18, 2006 11:18 PM
Subject: Re: [ukmicrowaves] Heather Hall


> Ian Lamb wrote:
>> Andy, you wouldn't want to live up t'north would you????
>>
>>
>> Ian Lamb - G8KQW
>
>
> Nowt wrong wi' t'North tha naws.. Ah wuz born up 'ere o'coors.
>
> Peter, G3PHO
>

Hello Peter,
You're all Southerners to me!
Regards,
Eddie
(On a very sunny Tyneside)




Yahoo! Groups Links

<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ukmicrowaves/

<*> To unsubscribe from this group, send an email to:
ukmicrowaves-unsubscribe@...

<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/






ken ferguson
G0HYP IO84FN


Re: Heather Hall

Eddie G0EHV
 

----- Original Message -----
From: "Peter Day" <microwaves@blueyonder.co.uk>
To: <ukmicrowaves@yahoogroups.com>
Sent: Tuesday, April 18, 2006 11:18 PM
Subject: Re: [ukmicrowaves] Heather Hall


Ian Lamb wrote:
Andy, you wouldn't want to live up t'north would you????
Ian Lamb - G8KQW
Nowt wrong wi' t'North tha naws.. Ah wuz born up 'ere o'coors.
Peter, G3PHO
Hello Peter,
You're all Southerners to me!
Regards,
Eddie
(On a very sunny Tyneside)


Re: UKuG Microwave Contest 23, 13,9cm: Sunday 23 April 2006

Peter Day <microwaves@...>
 

g4bel wrote:
Hi All,
I should be on from home for most of the event, so please add me to your list Peter.
Will do... many thanks Roger.

Peter


Re: ENV 50166-2

Graham Shirville <g.shirville@...>
 

 Hi All,
 
Many many thanks to everyone who has provided the technical, ethical and H&S etc answers to my question!
 
I now have more than enough data and information to enable me to complete the form required at this stage and, as usual learnt a lot of information from this group.
 
I am now well armed to provide any further answers needed when, hopefully, we get the U/S transponder completed and when the integration takes place at the ESTEC facility in the Netherlands, and eventually, when pre-flight testing is undertaken at the launch facility in Kourou in French Guiana.
 
I greatly appreciate your help!
 
73
 
Graham G3VZV


Risk

Steve Bunting M0BPQ
 

Reg Wrote

"Am I right in assuming not any old Tom, Dick or harry can write one. Unless
you have done a course on how to structure etc. Then your not deemed a
competent person to do so? Reg G8VHI"

The issue here, Reg, is "Will a risk assessment done by a untrained person stand up in court should litigation start?" Most organizations' chief execs (who are now legally responsible for H&S) will answer "no" to that and therefore insist that people are trained. Training reduces the risk of a incorrect assessment!

In the environment that Graham is working I would be amazed if no-one is responsible for H&S and able advise on document format etc. However, Graham may not be able to pass the buck as the designated H&S person often consults a local procedural or technical expert to fill in gaps in his/her knowledge. I agree 100% with others that there is no legal substitute for measurement and compliance with standards, no matter how daft you think they are. Just be thankful that you don't have to get ethical approval for projects - that is a minefield in itself so don't get me started :-)

73
Steve


Re: ENV 50166-2

Mark GM4ISM <gm4ism@...>
 

The issue of competency is probably the biggest issue here.
Almost any adult can be deemed a competent person for the purpose of carrying out low level tasks with instructions.
To do a risk assessment may not require formal training, but someone with appropriate responsibility has to determine that the individual doing the assessment is competent to do it. This decision would probably also be recorded!
In this case, a person involved with the technical aspects of the activity,  with the relevant experience / training / knowledge of the hazard, and knowledge of any risk assessment protocols used in the organisation may be deemed competent.
Its a minefield!
Mark GM4ISM

----- Original Message -----
Sent: Wednesday, April 19, 2006 1:59 PM
Subject: Re: [ukmicrowaves] ENV 50166-2

In a message dated 19/04/2006 13:54:50 GMT Standard Time, gm4ism@... writes:
To reduce the chance of litigation, a risk assessment needs to be formally recorded and performed by a person competent to do it. You will get extremely high readings on an e-field probe like an EMR300  when in close proximity to the antenna.  There is no RF meter on the market that can accurately assess near field levels (within a few wavelengths of the antenna)  
Am I right in assuming not any old Tom, Dick or harry can write one. Unless you have done a course on how to structure etc. Then your not deemed a competent person to do so? Reg G8VHI


No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.385 / Virus Database: 268.4.3/317 - Release Date: 18/04/2006


Re: ENV 50166-2

Mark GM4ISM <gm4ism@...>
 

Gents,
Chris and Andy are both essentially right, but a couple of other points need to be raised.
The use of a calibrated hazard meter is essential for an assessment of the safety of the work environment, they can be hired from test gear suppliers like microlease and others (I have a few contacts of companies I have hired them from in the past, please contact me off list)
To reduce the chance of litigation, a risk assessment needs to be formally recorded and performed by a person competent to do it. You will get extremely high readings on an e-field probe like an EMR300  when in close proximity to the antenna.  There is no RF meter on the market that can accurately assess near field levels (within a few wavelengths of the antenna)  
The people working on the project need to be aware of the hazard and any control measures taken to reduce risk. The transmitter power is low. Even at a small distance the most pessimistic analysis to show field less than the levels indicated by current legislation. That is not including time averaging, which is a road I would not go down. The prescribed levels are not limits but if you treat them so you will be well on the side of safety.
My main concern is that someone could get their eyes significantly closer to the radiating element while the transmitter is on, and at the power levels indicated there is a small but finite risk of eye damage.. The eye cannot dissipate heat energy very well.
Possible control measures
Physically restricting approach to the antennas to a safe distance is probably best, though you may consider having a bright light next to the antenna that is on when the transmitter is running, to warn 'trained' personnel to keep their heads away.
The actual risk from this scenario seems to be quite low, but that risk assessment does need to be done properly, and to be seen to be done properly.
Again, please contact me off list, I may be able to help with informal or formal advice.
 
regards
Mark
GM4ISM
 

----- Original Message -----
Sent: Tuesday, April 18, 2006 9:30 PM
Subject: [ukmicrowaves] ENV 50166-2

 Hi All,
 
I am working on the SSETI-ESEO GTO satellite project with a planned U/S linear transponder and 400bps telemetry channel and need to quote some information about radiation levels that might be expected during integration and testing of the satellite referenced to the above pre-standard which is entitled "Human exposure to electromagnetic fields. High frequency (10 kHz to 300 GHz)"
 
The transmitter will be using approx 9 watts of RF at 2.4GHz probably split between two quadrilifar antennas.
 
Assuming that some "engineers" might be working within 1 or 2 metres of these antennas for some days and that the transmitters will be operational for say up to 5% of the time - would this exceed the maximum levels contained in the ENV or not?
 
I guess this is a simple question that will probably have a complicated answer but would appreciate any help ....
 
many thanks
 
Graham G3VZV


No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.385 / Virus Database: 268.4.3/317 - Release Date: 18/04/2006


UKuG Microwave Contest 23, 13,9cm: Sunday 23 April 2006

g4bel <RogerTaylor@...>
 

Hi All,

I should be on from home for most of the event, so please add me to
your list Peter.


G4BEL JO02BI Cambridge

23cm 300w 1.5m dish

13cm 60w 1.5m dish

9cm 50w 70cm dish.

73
Roger


ENV 50166-2

Chris Bartram <yahoo@...>
 

Do a simple back of envelope calculation first to get a ROM estimate, then if
it looks to be marginal look in more detail----
At 1 metre distance, area of a sphere = 4.pi.r^2 = 12.5m^2
You haven't stated the gain of the antennas, but lets say 5dBi (quad helix,
semi-omni coverage??) so EIRP from 9W split between 2 of these is 14 Watts
each.   On boresight, 14 watts if it were spread over 12.5m^2 = 1.1
W/m^2,  or 110uW/cm^2
Which is way below the 5mW/cm^2  nanny-state-imposed safety limit.
And with that margin, I don't think anyone in their right mind - even a
lawyer - is going to argue the near field enhancement game.
I couldn't dispute Andy's argument in a free-space environment, but in an
indoor environment, you also have to factor-in reflections, which can cause
large variations in field strength.

Incidentally, the current HPA exposure standard for amateur radio applications
above 23cm is 10W/m^2 (1mW/cm^2) averaged over 6min, so there's not that big
a margin in Andy's estimate...

If you are exposing people to radiation, you have a legal duty of care to
ensure that they are not exposed to levels above the statutory limits. A
back-of-envelope calculation would probably not be seen as adequate by a
Court... Systematic measurement with a calibrated instrument would be. I
guess that Andy and I have different attitudes wrt Health and Safety: I could
get sued if I get things wrong, I suspect Andy works under Crown Immunity!!


Vy 73

Chris
GW4DGU


Re: UKuG Microwave Contest 23, 13,9cm: Sunday 23 April 2006

Sean <m1ecy@...>
 

Hi All,

I will be working till 5pm, but will be happy to join in when I can -
At present only QRP on 23 cm from home - 10W to 4x23ele - I doubt the
PA will be ready by then......

Cheers
Sean
M1ECY


--- In ukmicrowaves@yahoogroups.com, Peter Day <microwaves@...> wrote:

Hello folks,

It's now the time to dust off the microwave gear that you've not been
using since last October!

The UK Microwave Group's first contest of 2006 takes place this coming
Sunday, 23rd April with the Low Band Contest on 23, 13 and 9cm...
scheduled from 0900GMT to 2000GMT.

Please try to come on if only for a short time. The portable stations
in particular would welcome contacts to justifiy the effort made to
get out on what might be a cold and rainy day!

Proposed activity reported to me so far is shown below. If you wish to
be on this list then let me know before Friday lunchtime as the last
version of this activity list will be emailed around my list on late
Friday evening.

Some of you may receive this twice if you get a direct version as well
as the one on the UKuG Microwave Reflector.



...........................................................................................................

UK MICROWAVE GROUP LOWBAND (23/13/9cm) CONTEST SUNDAY 23 APRIL 2006
-------------------------------------------------------------------

G3PHO/P:Either Yorkshire Wolds (IO93PW37) or Blakey Ridge, North
York Moors (IO94MI) (depends on how early I can get out of
bed!)
Active from 0900-1800GMT.
23cm: 18W to a 23 element Tonna
9cm: 16W to a 1.2m dish
13cm: Not available
144.175MHz ssb Talkback
Mobile phone: 07811 808605
KST: Only last resort... need another pair of hands
for this!

G0DPS/P:Oxenhope Moor, IO93FL12
23cm: 10 watts to 4 by 36 ele long yagis, about 433 mtrs asl

G8ACE: Unlikely to be /p now so operation from home at IO91IB.
9cm and 23cm bands.

G1EHF/P:IO80WP (Whiteways Hill on the Purbecks)
Operators:G3TCU (Phil), G4SJH (Barry), G3TCT (Graham) and G1EHF
(Dave)
1.3 GHz - 250W into 4 x 35 element
2.3 GHz - 10W into 25 element
3.4 GHz - 10W into 0.8m offset dish
Talkback: 144.175MHz and ON4KST

2E0CDJ: IO71XT Home station.
23cm: 10W to 2 x 35ele Tonnas
655ft asl.
(Welcome to the UK Microwave Group Daran !)

G4RFR/P:I080??: Flight RTefuelling HQ Wimborne, Dorset
M0EYT and G0NZO and possibly some other local
microwavers are planning to install 23, 13 and 9cm on the mast up at
the FRARS HQ.
Talk back: 144.175MHz ssb and KST r...

G3XDY: JO02OB Home station.
1.3GHz 200W to 4 x 23ele Yagis
2.3GHz 120W to 0.8m dish
3.4GHz 20W to 0.6m dish
ON4KST and 144.175MHz for talkback, but mostly CQing
around 1296.213MHz.


Cloverleaf

Chris Bartram <yahoo@...>
 

A member of our Club(MIDCARS) is trying to find information about a  Clover
Leaf antenna for 23Cms he built a few years ago form articles in VHF  Comms -
has anybody got a copy of the articles or any further information  please.
G8ATB
Somewhere in my junk boxes I have a 23cm clover leaf which I made in the 1980s
for mobile use. It worked surprisingly well.

If your friend can't find the VHF Comms article, I'd be happy to lend it to
him so he can copy it.

Vy 73

Chris
GW4DGU


UKuG Microwave Contest 23, 13,9cm: Sunday 23 April 2006

Peter Day <microwaves@...>
 

Hello folks,

It's now the time to dust off the microwave gear that you've not been
using since last October!

The UK Microwave Group's first contest of 2006 takes place this coming
Sunday, 23rd April with the Low Band Contest on 23, 13 and 9cm...
scheduled from 0900GMT to 2000GMT.

Please try to come on if only for a short time. The portable stations
in particular would welcome contacts to justifiy the effort made to
get out on what might be a cold and rainy day!

Proposed activity reported to me so far is shown below. If you wish to
be on this list then let me know before Friday lunchtime as the last
version of this activity list will be emailed around my list on late
Friday evening.

Some of you may receive this twice if you get a direct version as well
as the one on the UKuG Microwave Reflector.



...........................................................................................................

UK MICROWAVE GROUP LOWBAND (23/13/9cm) CONTEST SUNDAY 23 APRIL 2006
-------------------------------------------------------------------

G3PHO/P:Either Yorkshire Wolds (IO93PW37) or Blakey Ridge, North
York Moors (IO94MI) (depends on how early I can get out of
bed!)
Active from 0900-1800GMT.
23cm: 18W to a 23 element Tonna
9cm: 16W to a 1.2m dish
13cm: Not available
144.175MHz ssb Talkback
Mobile phone: 07811 808605
KST: Only last resort... need another pair of hands
for this!

G0DPS/P:Oxenhope Moor, IO93FL12
23cm: 10 watts to 4 by 36 ele long yagis, about 433 mtrs asl

G8ACE: Unlikely to be /p now so operation from home at IO91IB.
9cm and 23cm bands.

G1EHF/P:IO80WP (Whiteways Hill on the Purbecks)
Operators:G3TCU (Phil), G4SJH (Barry), G3TCT (Graham) and G1EHF (Dave)
1.3 GHz - 250W into 4 x 35 element
2.3 GHz - 10W into 25 element
3.4 GHz - 10W into 0.8m offset dish
Talkback: 144.175MHz and ON4KST

2E0CDJ: IO71XT Home station.
23cm: 10W to 2 x 35ele Tonnas
655ft asl.
(Welcome to the UK Microwave Group Daran !)

G4RFR/P:I080??: Flight RTefuelling HQ Wimborne, Dorset
M0EYT and G0NZO and possibly some other local
microwavers are planning to install 23, 13 and 9cm on the mast up at
the FRARS HQ.
Talk back: 144.175MHz ssb and KST r...

G3XDY: JO02OB Home station.
1.3GHz 200W to 4 x 23ele Yagis
2.3GHz 120W to 0.8m dish
3.4GHz 20W to 0.6m dish
ON4KST and 144.175MHz for talkback, but mostly CQing
around 1296.213MHz.


Re: Clover Leaf attena

Jonathan Naylor <naylorjs@...>
 

I am sure that there was a clover leaf antenna design in the 1970s
vintage VHF Manual from the ARRL.

Jonathan ON/G4KLX


Re: Clover Leaf attena

Chris G8BKE
 

VHF Comms 4/1979 has a 23cms Big Wheel (clover leaf?) antenna article in it by DD0QT..do you want a
copy?

73 de Chris G8BKE

Web Site:-
http://www.qsl.net/g8bke/index.html





Hi all

A member of our Club(MIDCARS) is trying to find information about a Clover Leaf antenna for 23Cms he
built a few years ago form articles in VHF Comms - has anybody got a copy of the articles or any
further information please.

G8ATB

"Many years ago I was given a article for a Clover leaf and 4ele beam for 1296 to use with a
Microwave converter. I see from this VHF Comms site that two articles are listed
DD0OT 1973/2 page 110-115 Clover leaf.
DC8XB 1980/1 page 203-207 4ele beam."


Re: Clover Leaf attena

Andy Rutter, G8HCK
 

G3at@aol.com wrote:

Hi all
A member of our Club(MIDCARS) is trying to find information about a Clover Leaf antenna for 23Cms he built a few years ago form articles in VHF Comms - has anybody got a copy of the articles or any further information please.
G8ATB
"Many years ago I was given a article for a Clover leaf and 4ele beam for 1296 to use with a Microwave converter. I see from this VHF Comms site that two articles are listed
DD0OT 1973/2 page 110-115 Clover leaf.
DC8XB 1980/1 page 203-207 4ele beam."


I don't have 1973/2, but there is no reference to the Clover Leaf article in the 1973 index. I do have 1979/4 which has 'Big Wheel - An Omnidirectional Antenna for the 23cm Band' by DD0QT. Could this be the article you need?

I think your VHF Comms references are a little awry - the 4 ele beam article by DC8XB is actually 1971/3 pg 132-133 - or maybe these are not from the UK version.

--
Andy, g8hck


Re: ENV 50166-2

regwoolley@...
 

In a message dated 19/04/2006 13:54:50 GMT Standard Time, gm4ism@... writes:
To reduce the chance of litigation, a risk assessment needs to be formally recorded and performed by a person competent to do it. You will get extremely high readings on an e-field probe like an EMR300  when in close proximity to the antenna.  There is no RF meter on the market that can accurately assess near field levels (within a few wavelengths of the antenna)  
Am I right in assuming not any old Tom, Dick or harry can write one. Unless you have done a course on how to structure etc. Then your not deemed a competent person to do so? Reg G8VHI


Re: ENV 50166-2

Mark GM4ISM <gm4ism@...>
 

Gents,
Chris and Andy are both essentially right, but a couple of other points need to be raised.
The use of a calibrated hazard meter is essential for an assessment of the safety of the work environment, they can be hired from test gear suppliers like microlease and others (I have a few contacts of companies I have hired them from in the past, please contact me off list)
To reduce the chance of litigation, the risk assessment needs to be formally recorded and performed by a person competent to do it. You will get extremely high readings on an e-field probe like an EMR300  when in close proximity to the antenna.  There is no RF meter on the market that can accurately assess near field levels (within a few wavelengths of the antenna)  
The people working on the project need to be aware of the hazard and any control measures taken to reduce risk. The transmitter power is low. Even at a small distance the most pessimistic analysis to show field less than the levels indicated by current legislation. That is not including time averaging, which is a road I would not go down. The prescribed levels are not limits but if you treat them so you will be well on the side of safety.
My main concern is that someone could get their eyes significantly closer to the radiating element while the transmitter is on, and at the power levels indicated there is a small but finite risk of eye damage.. The eye cannot dissipate heat energy very well.
Possible control measures
Physically restricting approach to the antennas to a safe distance is probably best, though you may consider having a bright light next to the antenna that is on when the transmitter is running, to warn 'trained' personnel to keep their heads away.
The actual risk from this scenario seems to be quite low, but that risk assessment does need to be done properly, and to be seen to be done properly.
Again, please contact me off list, I may be able to help with informal or formal advice.
 
regards
Mark
GM4ISM
 
 

----- Original Message -----
Sent: Tuesday, April 18, 2006 9:30 PM
Subject: [ukmicrowaves] ENV 50166-2

 Hi All,
 
I am working on the SSETI-ESEO GTO satellite project with a planned U/S linear transponder and 400bps telemetry channel and need to quote some information about radiation levels that might be expected during integration and testing of the satellite referenced to the above pre-standard which is entitled "Human exposure to electromagnetic fields. High frequency (10 kHz to 300 GHz)"
 
The transmitter will be using approx 9 watts of RF at 2.4GHz probably split between two quadrilifar antennas.
 
Assuming that some "engineers" might be working within 1 or 2 metres of these antennas for some days and that the transmitters will be operational for say up to 5% of the time - would this exceed the maximum levels contained in the ENV or not?
 
I guess this is a simple question that will probably have a complicated answer but would appreciate any help ....
 
many thanks
 
Graham G3VZV


No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.385 / Virus Database: 268.4.3/317 - Release Date: 18/04/2006