Date   

Re: But it's the wrong satellite, Grommit.

Andy
 

On 27/06/2020 17:51, Andy G4JNT wrote:
https://www.theguardian.com/science/2020/jun/26/satellite-experts-oneweb-investment-uk-galileo-brexit
I can't imagine that a range of decision makers can be that foolish or forced by government pressures.    Anyone know the real story? (and, more to the point, are allowed to revel properly)
The FT (hidden behind a paywall) went on saying the idea was not to build another GPS system.

The FT quote is

"Moreover, the US was pushing its partner in the Five Eyes intelligence-sharing alliance to avoid replicating the GPS system, said three people with knowledge of the situation. “The Americans do not think a British Galileo would be sufficiently different to GPS,” said one. “They understand the vulnerabilities of GPS. They want something technologically different.”

"US officials had been drawn to the idea that important navigation technology could be “hidden in plain sight” on up to 80 of OneWeb’s planned 648 satellites, making them harder to compromise, according to two people who held discussions with both US defence officials and the UK government.

"In early March, Stuart Martin, chief executive of the Satellite Applications Catapult, told the Financial Times that while it would be challenging to develop this “cutting-edge” technology on satellites at low orbit, the UK had the expertise and it would be highly exportable.

"“This would offer something genuinely different that enhances GPS,” he said. “It is another way to achieve a global system at lower cost and it makes more economic sense.”"



LOCSTAR was cancelled part-way through because, we know now, but didn't then,  people had looked to the future and seen GPS coming along .
There's nothing inherently wrong in principle with a location system based on LEO satellites.  TRANSIT did it in teh 1960s using V/UHF - but not to anyhting like such accuracy.  100s of metres ISTR
GPS was known about in the mid 80s to the right people.

I had a mate at university in 1983 who did his final year project on TRANSIT. Then he did a PhD. on satellite navigation and used to receive 9track tapes from the US which had the kind of data you should receive for the replacement for TRANSIT. One he got his PhD. he was snapped up by a US company (Hughes or TRW ISTR) and worked on GPS technology till a lucky stock options gamble paid off and he retired in his 40s.


Andy
(The other one)


Bits for sale

Reg Woolley
 
Edited


Hi all I have just been to a friends garden shed in Peterborough.  He has large amounts of cable and other bits for sale. From SMA cables up to ldf 5 50 and much in between.  Even some dummy loads and other stuff. Attached is just a small example of what he has. 

For more info e mail r.halliday@...

Reg G8VHI


Sent from my Samsung Galaxy S10e - Powered by Three


Re: Low ESR Capacitors - Part 2

Chris Bartram G4DGU
 

However, he says after being tempted away from the computer ... Making ESR measurements of RF capacitors is a different matter. Probably the best way is to use a calibrated network analyser, I guess that one of the £50 Chinese jobbies would be able to do the job, but whatever you use, it does require _good_ cal. standards to make realistic measurements. Sadly, you don't get those thrown-in with most affordable net.ans.

In practice most 1206, 0805 and 0402 SMD capacitors below 100pF can probably be assumed to be COG/NPO, and probably low loss, but there will always be exceptions ...

73

Chris G4DGU


Re: But it's the wrong satellite, Grommit.

Chris M0WEF
 

Why would it be infeasible to put atomic clocks on LEO satellites?

Chris.


Re: But it's the wrong satellite, Grommit.

Robin Szemeti - G1YFG
 

From what I read, the system would not be a true stand alone PTN system, but would piggyback on the GPS system as an enhancement, delivering stronger signals into deep attenuation areas such as inside buildings ... and this is what encouraged the US military to give it the thumbs-up, as they would still ultimately be in control.


On Sat, 27 Jun 2020 at 17:51, Andy G4JNT <andy.g4jnt@...> wrote:

I can't imagine that a range of decision makers can be that foolish or forced by government pressures.    Anyone know the real story? (and, more to the point, are allowed to revel properly)

Back in 1990, long before GPS, I worked on a satellite location system based on two way transponders carrying spread spectrum signals for ranging.   The    LOCSTAR project.  I don't recall the full constellation, but think is was two sats in Geostationary and worked with a-priori information on approximate (eg country, location beforehand.   Probably just aimed at just part of the World like Eu.     The US had a not-dissimilar system, GEOSTAR in the pipeline.  NOt sure whether it went ahead fully.

LOCSTAR was cancelled part-way through because, we know now, but didn't then,  people had looked to the future and seen GPS coming along .

There's nothing inherently wrong in principle with a location system based on LEO satellites.  TRANSIT did it in teh 1960s using V/UHF - but not to anyhting like such accuracy.  100s of metres ISTR

If used in the same way as GNSS, they'd all have to carry highly accurate clocks Cs or Rb  which is totally infeasible (? nowadays ?).   But it's not unreasonable to use them as transponders carrying a ranging PN sequence transmitted from the ground.   Then the same correlation techniques can be carried out by users as with satellite generated PN codes.  Of course, satellite ephemeris will have to be known to cm accuracy if it's to match the performance of GNSS.   But given this, and a transponder payload with good phase stability for the PN code it's feasible I'd have thought.

The  ground station requirements are a bit frightening though.

As for mass produced low cost receivers.  IF the frequency band is around the same as GNSS, ie L-Band, I can see all those GNSS chip set manufacturers just yawning and building in compatibility.   After all, they upgraded from GPS to GLONASS,  Beidou, Galileo and I think there's another they work with now as well all in one tiny module costing a few quid.    It's all just IP/Firmare/juggling with numbers.


Re: Low ESR Capacitors

Chris Bartram G4DGU
 

FWIW, I use a 'Multifunction Transistor Tester Diodes LCR - TC1 Full Color Graphics Display' bought off Epay for about a tenner. Probably not accurate by lab standards, but a quick shotgun test using a 4.7uF polyester capacitor and a series resistor gave realistic results. It's certainly been good enough to detect a couple of high-ESR aluminium electrolytics in my spec.an.

73

Chris

G4DGU



But it's the wrong satellite, Grommit.

Andy G4JNT
 


I can't imagine that a range of decision makers can be that foolish or forced by government pressures.    Anyone know the real story? (and, more to the point, are allowed to revel properly)

Back in 1990, long before GPS, I worked on a satellite location system based on two way transponders carrying spread spectrum signals for ranging.   The    LOCSTAR project.  I don't recall the full constellation, but think is was two sats in Geostationary and worked with a-priori information on approximate (eg country, location beforehand.   Probably just aimed at just part of the World like Eu.     The US had a not-dissimilar system, GEOSTAR in the pipeline.  NOt sure whether it went ahead fully.

LOCSTAR was cancelled part-way through because, we know now, but didn't then,  people had looked to the future and seen GPS coming along .

There's nothing inherently wrong in principle with a location system based on LEO satellites.  TRANSIT did it in teh 1960s using V/UHF - but not to anyhting like such accuracy.  100s of metres ISTR

If used in the same way as GNSS, they'd all have to carry highly accurate clocks Cs or Rb  which is totally infeasible (? nowadays ?).   But it's not unreasonable to use them as transponders carrying a ranging PN sequence transmitted from the ground.   Then the same correlation techniques can be carried out by users as with satellite generated PN codes.  Of course, satellite ephemeris will have to be known to cm accuracy if it's to match the performance of GNSS.   But given this, and a transponder payload with good phase stability for the PN code it's feasible I'd have thought.

The  ground station requirements are a bit frightening though.

As for mass produced low cost receivers.  IF the frequency band is around the same as GNSS, ie L-Band, I can see all those GNSS chip set manufacturers just yawning and building in compatibility.   After all, they upgraded from GPS to GLONASS,  Beidou, Galileo and I think there's another they work with now as well all in one tiny module costing a few quid.    It's all just IP/Firmare/juggling with numbers.


Re: Low ESR Capacitors

Gordon REASON <gordonj.reason@...>
 

I made one up , from a simple circuit , taken fron google .........

Analogue panel meter ........ works fine .........

get's used about every five years or so , if I can find it !

On 27 June 2020 at 16:40 "Michael Scott via groups.io" <g3lyp@...> wrote:

Following the recent discussion on low ESR capacitors ( 7L18 ), what is a reliable method of measurement of ESR? Peak do a meter for around £100, but there are several cheaper multimeters which claim to be able to measure ESR.
 
Has anyone any advice/experience of these devices.
 
I am asking because the subject has come up recently when I have been asked for capacitors from the Chipbank for Sam’s Iceni and other transverters. Many of the capacitors I have in stock were given to me in plastic pots with no information other than the capacitance value. Sam specifies COG/NPO for most of his designs, and in some cases I have reels where the spec or code is given and I can track back to a datasheet, but for the loose ones it is pot luck what you get!
 
73,
 
Mike G3LYP
 
From: Paul G8KFW
Sent: Saturday, June 27, 2020 2:54 PM
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 

Hi

 

This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups

 

and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement

But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive

 

Regards Paul

 


From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?

 

Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot. 

Question,  what's the opinion on what type to use for the replacements?

Paul

 

-------- Original message --------

From: Paul G8KFW <paul@...>

Date: 26/06/2020 23:57 (GMT+00:00)

To: UKMicrowaves@groups.io

Subject: Re: [UKMicrowaves] 7L18?

 

Hi Ben

 

The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors

 

Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results

Then replace the suspect ones

 

Regards Paul B

 


From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?

 

Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?

 

Only mine has a problem.

 

Ben

--------------------------------------

Curator, Owner and Display coordinator

Military Wireless Museum

Kidderminster , UK .

 

This message was meant for the recipient

Any likeness to persons living or dead is odd

---------------------------------------

 

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


 


 


F1JGP 10GHz PA

Adrian G4UVZ
 

Built from an original F1JGP PCB fitted with a genuine FLM1011-8F Fet 
12 volt single supply and output monitor etc see attached details...delivering 5 -6 watts when last used about a year ago ...would probably benefit from snowflaking!
Please PM me with offers if interested..


Re: Low ESR Capacitors

Michael Scott
 

Sorry Ben, we have been chastised for going off topic without changing the subject line!!
 
Mike.
 

From: militaryoperator via groups.io
Sent: Saturday, June 27, 2020 4:44 PM
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Low ESR Capacitors
 
 
Following the recent discussion on low ESR capacitors ( 7L18 ),
Thanks for changing the subject line Mike. 
 
Every time a 7L18 popped up I was hoping for a solution, hi.
 
Ben

 
 
-----Original Message-----
From: Michael Scott via groups.io <g3lyp@...>
To: UKMicrowaves@groups.io
Sent: Sat, 27 Jun 2020 16:40
Subject: [UKMicrowaves] Low ESR Capacitors

Following the recent discussion on low ESR capacitors ( 7L18 ), what is a reliable method of measurement of ESR? Peak do a meter for around £100, but there are several cheaper multimeters which claim to be able to measure ESR.
 
Has anyone any advice/experience of these devices.
 
I am asking because the subject has come up recently when I have been asked for capacitors from the Chipbank for Sam’s Iceni and other transverters. Many of the capacitors I have in stock were given to me in plastic pots with no information other than the capacitance value. Sam specifies COG/NPO for most of his designs, and in some cases I have reels where the spec or code is given and I can track back to a datasheet, but for the loose ones it is pot luck what you get!
 
73,
 
Mike G3LYP
 
From: Paul G8KFW
Sent: Saturday, June 27, 2020 2:54 PM
Subject: Re: [UKMicrowaves] 7L18?
 
Hi
 
This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups
 
and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement
But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive
 
Regards Paul
 

From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 
Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot. 
Question,  what's the opinion on what type to use for the replacements?
Paul
 
-------- Original message --------
From: Paul G8KFW <paul@...>
Date: 26/06/2020 23:57 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 
Hi Ben
 
The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors
 
Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results
Then replace the suspect ones
 
Regards Paul B
 

From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?
 
Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?
 
Only mine has a problem.
 
Ben
--------------------------------------
Curator, Owner and Display coordinator
Military Wireless Museum
Kidderminster, UK.
 
This message was meant for the recipient
Any likeness to persons living or dead is odd
---------------------------------------
 
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.

--
Paul Bicknell G8KFW   South Coast UK
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.

--
Paul Bicknell G8KFW   South Coast UK


Re: Low ESR Capacitors

Neil Smith G4DBN
 

I use a Hutale LCR meter from Dr Le Hung. Must put it into a box.  Comes with kelvin clips.  Does all sorts as well as LCR.

Neil G4DBN

http://lcr.is-best.net/en/LCR_eng.pdf



On 27/06/2020 16:40, Michael Scott via groups.io wrote:
Following the recent discussion on low ESR capacitors ( 7L18 ), what is a reliable method of measurement of ESR? Peak do a meter for around £100, but there are several cheaper multimeters which claim to be able to measure ESR.
 
Has anyone any advice/experience of these devices.
 
I am asking because the subject has come up recently when I have been asked for capacitors from the Chipbank for Sam’s Iceni and other transverters. Many of the capacitors I have in stock were given to me in plastic pots with no information other than the capacitance value. Sam specifies COG/NPO for most of his designs, and in some cases I have reels where the spec or code is given and I can track back to a datasheet, but for the loose ones it is pot luck what you get!
 
73,
 
Mike G3LYP
 


Re: Low ESR Capacitors

militaryoperator
 


Following the recent discussion on low ESR capacitors ( 7L18 ),
Thanks for changing the subject line Mike. 

Every time a 7L18 popped up I was hoping for a solution, hi. 

Ben



-----Original Message-----
From: Michael Scott via groups.io <g3lyp@...>
To: UKMicrowaves@groups.io
Sent: Sat, 27 Jun 2020 16:40
Subject: [UKMicrowaves] Low ESR Capacitors

Following the recent discussion on low ESR capacitors ( 7L18 ), what is a reliable method of measurement of ESR? Peak do a meter for around £100, but there are several cheaper multimeters which claim to be able to measure ESR.
 
Has anyone any advice/experience of these devices.
 
I am asking because the subject has come up recently when I have been asked for capacitors from the Chipbank for Sam’s Iceni and other transverters. Many of the capacitors I have in stock were given to me in plastic pots with no information other than the capacitance value. Sam specifies COG/NPO for most of his designs, and in some cases I have reels where the spec or code is given and I can track back to a datasheet, but for the loose ones it is pot luck what you get!
 
73,
 
Mike G3LYP
 
From: Paul G8KFW
Sent: Saturday, June 27, 2020 2:54 PM
Subject: Re: [UKMicrowaves] 7L18?
 
Hi
 
This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups
 
and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement
But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive
 
Regards Paul
 

From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 
Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot. 
Question,  what's the opinion on what type to use for the replacements?
Paul
 
-------- Original message --------
From: Paul G8KFW <paul@...>
Date: 26/06/2020 23:57 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 
Hi Ben
 
The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors
 
Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results
Then replace the suspect ones
 
Regards Paul B
 

From: UKMicrowaves@groups.io [mailto: UKMicrowaves@groups.io ] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?
 
Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?
 
Only mine has a problem.
 
Ben
--------------------------------------
Curator, Owner and Display coordinator
Military Wireless Museum
Kidderminster, UK.
 
This message was meant for the recipient
Any likeness to persons living or dead is odd
---------------------------------------
 
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.

--
Paul Bicknell G8KFW   South Coast UK
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.

--
Paul Bicknell G8KFW   South Coast UK


Re: 23cm skeds

militaryoperator
 

Hi everyone

Just to mention that I have a regular sked with Graham, G3SGC on Fridays at 1000 starting on 144.250Mhz then QSYing to 1296.220Mhz around 1020. From Shrewsbury IO82OQ. Graham is on the North Norfolk coast at Sea Palling. We never fail to make it. Last week 5-4-9 both ways and good enough for SSB.
So if anyone is within the path please call or arrange another sked. 

Many thanks.... Ken G3UDA
_._,_._,_


Might be a bit of a trip for me Ken. 

norfolk.jpg

Ben G4BXD


Low ESR Capacitors

Michael Scott
 

Following the recent discussion on low ESR capacitors ( 7L18 ), what is a reliable method of measurement of ESR? Peak do a meter for around £100, but there are several cheaper multimeters which claim to be able to measure ESR.
 
Has anyone any advice/experience of these devices.
 
I am asking because the subject has come up recently when I have been asked for capacitors from the Chipbank for Sam’s Iceni and other transverters. Many of the capacitors I have in stock were given to me in plastic pots with no information other than the capacitance value. Sam specifies COG/NPO for most of his designs, and in some cases I have reels where the spec or code is given and I can track back to a datasheet, but for the loose ones it is pot luck what you get!
 
73,
 
Mike G3LYP
 

From: Paul G8KFW
Sent: Saturday, June 27, 2020 2:54 PM
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?
 

Hi

 

This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups

 

and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement

But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive

 

Regards Paul

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?

 

Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot. 

Question,  what's the opinion on what type to use for the replacements?

Paul

 

-------- Original message --------

From: Paul G8KFW <paul@...>

Date: 26/06/2020 23:57 (GMT+00:00)

To: UKMicrowaves@groups.io

Subject: Re: [UKMicrowaves] 7L18?

 

Hi Ben

 

The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors

 

Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results

Then replace the suspect ones

 

Regards Paul B

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?

 

Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?

 

Only mine has a problem.

 

Ben

--------------------------------------

Curator, Owner and Display coordinator

Military Wireless Museum

Kidderminster, UK.

 

This message was meant for the recipient

Any likeness to persons living or dead is odd

---------------------------------------

 

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


Re: 23cm skeds

Robin Szemeti - G1YFG
 

Just to clarify .. is that 10am or 10pm?

On Sat, 27 Jun 2020 at 15:44, Robin Szemeti <robin@...> wrote:
I'll have a go .. I am SSB only though  .. IO82UJ

On Sat, 27 Jun 2020 at 09:59, Ken Linney via groups.io <cycle_guy256=yahoo.co.uk@groups.io> wrote:
Hi everyone

Just to mention that I have a regular sked with Graham, G3SGC on Fridays at 1000 starting on 144.250Mhz then QSYing to 1296.220Mhz around 1020. From Shrewsbury IO82OQ. Graham is on the North Norfolk coast at Sea Palling. We never fail to make it. Last week 5-4-9 both ways and good enough for SSB.
So if anyone is within the path please call or arrange another sked. 

Many thanks.... Ken G3UDA


Re: 23cm skeds

Robin Szemeti - G1YFG
 

I'll have a go .. I am SSB only though  .. IO82UJ

On Sat, 27 Jun 2020 at 09:59, Ken Linney via groups.io <cycle_guy256=yahoo.co.uk@groups.io> wrote:
Hi everyone

Just to mention that I have a regular sked with Graham, G3SGC on Fridays at 1000 starting on 144.250Mhz then QSYing to 1296.220Mhz around 1020. From Shrewsbury IO82OQ. Graham is on the North Norfolk coast at Sea Palling. We never fail to make it. Last week 5-4-9 both ways and good enough for SSB.
So if anyone is within the path please call or arrange another sked. 

Many thanks.... Ken G3UDA


Re: 7L18?

Robin Szemeti - G1YFG
 

Electrolytic with a suitable ceramic strapped across it will usually suffice.



On Sat, 27 Jun 2020 at 14:54, Paul G8KFW <paul@...> wrote:

Hi

 

This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups

 

and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement

But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive

 

Regards Paul

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?

 

Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot.  

Question,  what's the opinion on what type to use for the replacements?

Paul

 

-------- Original message --------

From: Paul G8KFW <paul@...>

Date: 26/06/2020 23:57 (GMT+00:00)

Subject: Re: [UKMicrowaves] 7L18?

 

Hi Ben

 

The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors

 

Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results

Then replace the suspect ones

 

Regards Paul B

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?

 

Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?

 

Only mine has a problem. 

 

Ben

--------------------------------------

Curator, Owner and Display coordinator

Military Wireless Museum

Kidderminster, UK.

 

This message was meant for the recipient

Any likeness to persons living or dead is odd

---------------------------------------

 

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
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Paul Bicknell G8KFW   South Coast UK

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Re: 7L18?

Paul G8KFW
 

Hi

 

This is a subject that has been talked about a lot over the last 2 plus years on the HP Groups

 

and in general unless it is a switch mode power supply the replacement with a good quality ( not a copy ) non tantalum is considered a good replacement

But Low ESR capacitors  are quit often required for switch mode power used on certain HP equipment   but they are a lot more expensive

 

Regards Paul

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Paul Randall G3NJV
Sent: 27 June 2020 09:24
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 7L18?

 

Ditto for three Racal 1792 receivers I acquired. Dozens of tantalum caps faulty. I'd say,  if you find more than one or two faulty,  bite the bullet and replace the lot.  

Question,  what's the opinion on what type to use for the replacements?

Paul

 

-------- Original message --------

From: Paul G8KFW <paul@...>

Date: 26/06/2020 23:57 (GMT+00:00)

To: UKMicrowaves@groups.io

Subject: Re: [UKMicrowaves] 7L18?

 

Hi Ben

 

The last 7L18 I worked on required replacement of a large number of  Tantalum capacitors

 

Suggest you get an ESR meter and look at all the caps first don’t unsolder them just do the testing in CCT  and record the results

Then replace the suspect ones

 

Regards Paul B

 


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of militaryoperator via groups.io
Sent: 26 June 2020 22:35
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] 7L18?

 

Does anyone have experience of working on the 7L18 spectrum analyser in the 7603 mainframe?

 

Only mine has a problem. 

 

Ben

--------------------------------------

Curator, Owner and Display coordinator

Military Wireless Museum

Kidderminster, UK.

 

This message was meant for the recipient

Any likeness to persons living or dead is odd

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No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


Activity List for the UK Microwave Group 5.7GHz and 10GHz Contests - Sunday 28th June

John Quarmby
 

Here is the list for tomorrow's contest. The weather forecast looks like it will be breezy, but mainly dry, with no major rain scatter likely.

The contest runs from 0600 - 1800 GMT (0700 - 1900 BST) and entrants can choose any 8 hours within that period for their activity. Full rules are here:

https://www.microwavers.org/files/2020-mwrules_v6.pdf

Good luck to all entrants and I look forward to your logs.

73

John G3XDY
UKuG Contest Manager

Callsign: G4BXD
Locator: IO82UJ
Bands:  10GHz 0.3W 0.6m dish
Talkback: ON4KST 144/39  1296.2
Times: Various throughout


Callsign: G4ZTR
Locator: JO01KW
Band: 10GHz, 10w, 1m dish
Talkback: ON4KST
Times: Various, to suit observed activity

Callsign: G1PPA/P
Locator: IO93RI
Bands: 3cm 4w 1.2mtre dish
Times: approx 12pm until end if enough activity
Talkback: KST and SHF zello

Callsign: G4SJH/P
Locator: IO91GI
Bands:  10GHz 1W 0.85m dish
Talkback: ON4KST preferred or maybe 2m
Times: From around 10:30 BST

Callsign: G1EHF/P
Locator: IO91GI
Bands: 5.7GHz 10W 0.75m dish
Talkback: ON4KST preferred or maybe 2m
Times: From around 10:30 BST

  Callsign: G4JNT
  Locator: IO90IV58
  Bands: 5.7GHz 8W 30cm  flat plate
  Talkback: ON4KST
  Times: Various throughout

Callsign: G3XDY
Locator: JO02OB
Bands: 5.7GHz 15W 0.6m dish
             10GHz 10W 0.6m dish
Talkback: ON4KST or Zello SHF Chat
Times: Various throughout



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9cm ?

militaryoperator
 

on 9cm now. 

on kst2me as well



--------------------------------------
Curator, Owner and Display coordinator
Military Wireless Museum
Kidderminster, UK.

This message was meant for the recipient
Any likeness to persons living or dead is odd
---------------------------------------


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