Date   

Re: Substrate thickness for 10 GHz

Robin Szemeti - G1YFG
 

And if you want really thin susbsrate jlc do 4 layer, with either 0.2mm top layer (jlc7638 layer stackup) or 0.1mm (jlc 2213 stackup) ... no use for the hmc pa chip, but useful for other microwave projects where thermal is not an issue.


On Sat, 21 Aug 2021, 14:12 Chris Ruddy MM0KOS via groups.io, <mm0kos=yahoo.co.uk@groups.io> wrote:

Hi Greg

 

JLC PCB does boards of both 0.4 and 0.6. Ive always had a great service form them but be selective on the postage to keep your costs down

 

Chris MM0KOS

 

Sent from Mail for Windows

 

From: Greg - ZL3IX
Sent: 21 August 2021 07:17
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Substrate thickness for 10 GHz

 

I've now completed my 10 GHz transverter and am starting on an LNA and PA. For the transverter I used PCBs with a 0.8 mm FR4 substrate and, apart from the 1 dB per inch track loss, it seemed to work out well. I have been thinking of using a thinner substrate for the LNA and PA, to minimise both the inductance and the thermal resistance of the vias. I have looked at both 0.4 mm and 0.6 mm substrates but the supplier I have been using puts a heavy engineering charge on to the 0.4 mm boards, resulting in a $50 + cost, compared with just $2 for the 0.6 mm option.

Does anyone have any opinion about the use of 0.6 mm vs 0.4 mm substrates in this application? Issues are obviously via inductance on the FET source connections that will affect the noise figure, and the via thermal conductivity under the paddle of the HMC952 device. The latter needs to lose about 8 W of heat.

73, Greg, ZL3IX

 


--
Robin Szemeti - G1YFG


Scatterpoint input

Roger Ray
 

I would really appreciate some input for Scatterpoint, due to be published next week.
Such as  This month I have been…..  An article would be great.  Or anything interesting…….
Activity reports should go via John G4BAO as usual.  Next Tuesday certainly looks hopeful for the rsgb high band contest.
Thanks
Roger


Re: Substrate thickness for 10 GHz

Chris Ruddy MM0KOS
 

Hi Greg

 

JLC PCB does boards of both 0.4 and 0.6. Ive always had a great service form them but be selective on the postage to keep your costs down

 

Chris MM0KOS

 

Sent from Mail for Windows

 

From: Greg - ZL3IX
Sent: 21 August 2021 07:17
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Substrate thickness for 10 GHz

 

I've now completed my 10 GHz transverter and am starting on an LNA and PA. For the transverter I used PCBs with a 0.8 mm FR4 substrate and, apart from the 1 dB per inch track loss, it seemed to work out well. I have been thinking of using a thinner substrate for the LNA and PA, to minimise both the inductance and the thermal resistance of the vias. I have looked at both 0.4 mm and 0.6 mm substrates but the supplier I have been using puts a heavy engineering charge on to the 0.4 mm boards, resulting in a $50 + cost, compared with just $2 for the 0.6 mm option.

Does anyone have any opinion about the use of 0.6 mm vs 0.4 mm substrates in this application? Issues are obviously via inductance on the FET source connections that will affect the noise figure, and the via thermal conductivity under the paddle of the HMC952 device. The latter needs to lose about 8 W of heat.

73, Greg, ZL3IX

 


Re: RS

John Lemay
 

Hello David

 

There’s certainly a lot of rain around today, although so far Essex is living up to its reputation and is dry.

 

I’m still learning about RS propagation, but my feeling is that with blanket coverage the prospects of RS are quite limited. But don’t let me put you off, and I’ll take a listen to beacons later and loiter on ‘KST if it looks promising.

 

Regards

 

John G4ZTR

 

 

From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Dave - G4RQI
Sent: 20 August 2021 18:58
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] RS

 

Hello...

 

There’s quite a bit rain about tomorrow so anyone around in the afternoon on 10Ghz?

 

I’ll log into KST when I’m about

 

David – G4RQI IO93IR

Sent from Mail for Windows

 


GB3GCT o 10368.935MHz

John Fell
 

Aggressive drizzle here at moment .
Once again it shows that it only takes minimal moisture to bring GB3GCT from normal below noise floor to a respectable level .My 60cm dish is also elevated to 4 degrees to maximise the signal shown.

73
John
G0API
IO80XS77JR


Substrate thickness for 10 GHz

Greg - ZL3IX
 

I've now completed my 10 GHz transverter and am starting on an LNA and PA. For the transverter I used PCBs with a 0.8 mm FR4 substrate and, apart from the 1 dB per inch track loss, it seemed to work out well. I have been thinking of using a thinner substrate for the LNA and PA, to minimise both the inductance and the thermal resistance of the vias. I have looked at both 0.4 mm and 0.6 mm substrates but the supplier I have been using puts a heavy engineering charge on to the 0.4 mm boards, resulting in a $50 + cost, compared with just $2 for the 0.6 mm option.

Does anyone have any opinion about the use of 0.6 mm vs 0.4 mm substrates in this application? Issues are obviously via inductance on the FET source connections that will affect the noise figure, and the via thermal conductivity under the paddle of the HMC952 device. The latter needs to lose about 8 W of heat.

73, Greg, ZL3IX


Re: Modderman 23cms PA for sale with extras

Phil Williams
 

Hello Bob,  
PA is sold and winging its way to downtown Leicestershire  Sorry! 

Phil G3YPQ


Re: RS

Clive Elliott GW4MBS
 

David I might be around if there is something local to get me out the valley.
--
Clive GW4MBS (ex-G8ADP)
Pottering on 6m - 3cm in a valley in IO71XW where any QSO is a triumph of optimism over geography!


Re: 10 GHZ SSPAs

John Lambo
 

Hello Robin,
Thank you for the nice words.
Enjoy you sailing trip and take care..


73  John  PA7JB


Op 20-8-2021 om 19:00 schreef Robin Szemeti - G1YFG:

Nice units, i have one, not tested yet as i am sailing, but a really nice build

On Fri, 20 Aug 2021, 16:55 John Lambo, <pa7jb@...> wrote:

Hello Group,

We still have some 10ghz SSPAs for sale.

We think that there are amteurs who are not qrv from the moon but this is a nice amplifier for tropo.

Sent a mail to Jac if you want more info..

73  John  PA7JB off the EME Moonbounce Group









We have some nice modified 10GHz SSPAs for sale


PWR OUT:  18 - 22Watt 
PWR IN: 30 -70mW
DC V: 10.5V
DC A: 9 - 11A
Tuned on: 10368Mhz

The SSPA has a seperate DC board for +10V and -5V with protection
NO heatsink, VERY GOOD COOLING is a must !!!
It is almost Plug & Play
 
With a 1.8m dish and 18-20W@feed you will have a nice EME station !!


For info email direct to: Jac, PA3DZL    emailaddress = pa3dzl@... 

Dutch EME Moonbounce Group

PA0BAT Gerard, PA7JB John and PA3DZL Jac

 


--
Robin Szemeti - G1YFG



RS

Dave - G4RQI
 

Hello...

 

There’s quite a bit rain about tomorrow so anyone around in the afternoon on 10Ghz?

 

I’ll log into KST when I’m about

 

David – G4RQI IO93IR

Sent from Mail for Windows

 


Re: 10 GHZ SSPAs

Robin Szemeti - G1YFG
 

Nice units, i have one, not tested yet as i am sailing, but a really nice build


On Fri, 20 Aug 2021, 16:55 John Lambo, <pa7jb@...> wrote:

Hello Group,

We still have some 10ghz SSPAs for sale.

We think that there are amteurs who are not qrv from the moon but this is a nice amplifier for tropo.

Sent a mail to Jac if you want more info..

73  John  PA7JB off the EME Moonbounce Group









We have some nice modified 10GHz SSPAs for sale


PWR OUT:  18 - 22Watt 
PWR IN: 30 -70mW
DC V: 10.5V
DC A: 9 - 11A
Tuned on: 10368Mhz

The SSPA has a seperate DC board for +10V and -5V with protection
NO heatsink, VERY GOOD COOLING is a must !!!
It is almost Plug & Play
 
With a 1.8m dish and 18-20W@feed you will have a nice EME station !!


For info email direct to: Jac, PA3DZL    emailaddress = pa3dzl@... 

Dutch EME Moonbounce Group

PA0BAT Gerard, PA7JB John and PA3DZL Jac

 


--
Robin Szemeti - G1YFG


Re: ALC Overrun

Andrew Cartwright
 

Algenon,

Out of interest how did you get on? have you been using the transverter with your IC7100?  I ask because I am considering the very same route.

Regards

Andrew - G7MNS


10 GHZ SSPAs

John Lambo
 

Hello Group,

We still have some 10ghz SSPAs for sale.

We think that there are amteurs who are not qrv from the moon but this is a nice amplifier for tropo.

Sent a mail to Jac if you want more info..

73  John  PA7JB off the EME Moonbounce Group









We have some nice modified 10GHz SSPAs for sale


PWR OUT:  18 - 22Watt 
PWR IN: 30 -70mW
DC V: 10.5V
DC A: 9 - 11A
Tuned on: 10368Mhz

The SSPA has a seperate DC board for +10V and -5V with protection
NO heatsink, VERY GOOD COOLING is a must !!!
It is almost Plug & Play
 
With a 1.8m dish and 18-20W@feed you will have a nice EME station !!


For info email direct to: Jac, PA3DZL    emailaddress = pa3dzl@... 

Dutch EME Moonbounce Group

PA0BAT Gerard, PA7JB John and PA3DZL Jac

 


Re: Modderman 23cms PA for sale with extras

Bob Lockley VK6KW
 

Hi Phil,

Can you give me an estimate of the P&P to Australia 6401 please?

It would probably need to have the modules separated to pack efficiently. But as you suggest reworking of the layout is on the cards anyway.

73,

Bob VK6KW.

 

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Phil Williams
Sent: Friday, August 20, 2021 6:02 PM
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Modderman 23cms PA for sale with extras

 

Hello, I'm selling my Bert Modderman 2W in 140W out 23cms PA .
It built up in a rather basic way and works fine. Included is a 12v-28v 20A up converter and input and output relays.
Its only been used into a dummy load and then for a few minutes only.
You'd probably dismantle my efforts and do the job properly! The PA is as new and the relays are pretty valuable too.
I'm asking £270 plus £10 p+p to UK 
Phil G3YPQ 
N.Cornwall 


Modderman 23cms PA for sale with extras

Phil Williams
 

Hello, I'm selling my Bert Modderman 2W in 140W out 23cms PA .
It built up in a rather basic way and works fine. Included is a 12v-28v 20A up converter and input and output relays.
Its only been used into a dummy load and then for a few minutes only.
You'd probably dismantle my efforts and do the job properly! The PA is as new and the relays are pretty valuable too.
I'm asking £270 plus £10 p+p to UK 
Phil G3YPQ 
N.Cornwall 


Connectors

Colin Ranson
 

 

Further to Simon G0FCU, et al

 

M0MAT on ebay now stocks SMA compression plugs for TM LMR-240 at £4.49 or 4 for £3.95 each,  including post, https://www.ebay.co.uk/itm/154575829863 - a bit pricey, but if anyones willing to wait snail trail from China ....................

 

From RFstore2015 (223642254878) these can be had for £1.85 each with an initial postage of £1.54 for one, thereafter free.   Probably out of the same stable in China.

 

Regards to all

 

Colin de G8LBS.

 

 

 

Sent from Mail for Windows

 


Re: -- Was Waveguide Design - Book Recommendation

Mark GM4ISM
 

Hi Paul

 Be careful what you wish for :)

I developed a high dynamic range preamplifier based on the RFMW RFMC8818 device that has 16dB gain Nf below 2dB and an output P1dB of about +27dBm (at UHF) it should survive 1W on the input in theory

It was bomb proof at even unreasonable signal levels ( eg Cellular TX antenna  2m away)

The downside is that it would output about 800mW given a big signal (see below) and would be capable of frying subsequent stages

My calcs suggest  that a 100W 50MHz Tx  with 10dB gain antenna  pointed at a similar antenna 100m away will produce about 200mW into the frontend of the RX

The whole chain will need to be bombproof and perhaps have a pair of diodes as a limiter. When they start clipping you will get worse intermods too.

A lower gain device with reasonable nF (3dB or so) is probably more what you need

the PGA103 is good but will need an attenuator,   26dB gain at 50MHz is too much and that gain lowers the input overload level

the PHA1 is perhaps better

The last time I hit a rig with a lot of RF  on receive  it was not the front end device that expired, it was the pin diode band switches

On 19/08/2021 16:49, Paul G8AQA via groups.io wrote:
Hi Mark,

I was recently looking at nuvistors for a very high dynamic range preamp to work in very close proximity to a transmitter on 50 MHz. The idea is not to blow up the device if 2 beams are pointing at each other on rare occasions. I haven't done the sums yet. Probably need a switchable attenuator after it to avoid overloading the RX. Playing with ideas at the moment.

73
Paul G8AQA

On 19/08/2021 09:54, Mark GM4ISM via groups.io wrote:
Sounds good Chris, hope to work you on 3cm EME sometime

I was going to suggest casting a swept bend, electroforming one on an aluminium shaped mandrel or machining one from a block with CNC.. all quite a bit of effort but fun?

Glad you found something..   A clear case of one of the major rules of the junk box.

You don't know what you've got till you find it again / I wish I knew I had that before I spent  loads of time / money on another.

You don't need it until after you throw it away.

You know you've got one but cant find it.

I wonder if it will still work after all this time ... Bang

Oh no its gone rusty / filled with water / has critters living in it.

Why did i keep that? / What is it?

That was valuable once, now totally worthless and not worth using. (I just found a GAT5 in my microwave semiconductor drawer and some nuvistors)


Yep its clear-out time.  There's a lot in the last 4 categories, all soon to move to category 2

There are also a lot of great projects  coming back to the light

The joys of retirement!

Mark GM4ISM




On 19/08/2021 09:29, Chris Bartram G4DGU wrote:
Although I have been able to come to an understanding of waveguide operation and design techniques from a variety of sources, I've never really found a clearly comprehensible reference. Many books which claim to explain the subject seem more to want to show-off their author's extensive mathematical skills, than provide any form of clear explanation. I know that I'm not alone in finding this ...

Many times, I've noted references to the work of Theodore Moreno, and his 1944 book 'Microwave Transmission Design Data' but had never managed to find a copy for sale. This happened again while deciding on the best way to approach the design of a 68degree e-plane WG17 bend.

Needing some old books for for another research project (not related to engineering) I've discovered 'Abe Books' a French-owned multi-national grouping of secondhand booksellers (including many from the UK).  A quick look on the Abe web site showed several copies of Moreno's 1944 book (and later editions)at sensible prices, including a near mint softcover copy of the 1948 second edition published by Dover Books for not much more than UKP10. I bought that from a bookseller in Hamburg. It has now arrived, and the book has already been very useful in understanding the design of mitred e-plane waveguide bends.

With more thought, I've decided not to use a mitred bend (which can be made to work as well as a swept bend in a narrow-bandwidth application) as I discovered an additional treasury of WG17 parts in my garage! Amongst them are some easily modifiable swept WG17 e-plane bends ...

Chris

G4DGU









Virus-free. www.avg.com


Re: -- Was Waveguide Design - Book Recommendation

Andy G4JNT
 

Since you don't require a fantastic noise figure on 50MHz, you'll probably find a bipolar device is a better option.    One of  several GHz Ft medium power devices  running at 70mA Ic.     Or a PGA103 type modamp. 




On Thu, 19 Aug 2021 at 16:50, Paul G8AQA via groups.io <paulnick=btinternet.com@groups.io> wrote:
Hi Mark,

I was recently looking at nuvistors for a very high dynamic range preamp to work in very close proximity to a transmitter on 50 MHz. The idea is not to blow up the device if 2 beams are pointing at each other on rare occasions. I haven't done the sums yet. Probably need a switchable attenuator after it to avoid overloading the RX. Playing with ideas at the moment.

73
Paul G8AQA

On 19/08/2021 09:54, Mark GM4ISM via groups.io wrote:
Sounds good Chris, hope to work you on 3cm EME sometime

I was going to suggest casting a swept bend, electroforming one on an aluminium shaped mandrel or machining one from a block with CNC.. all quite a bit of effort but fun?

Glad you found something..   A clear case of one of the major rules of the junk box.

You don't know what you've got till you find it again / I wish I knew I had that before I spent  loads of time / money on another.

You don't need it until after you throw it away.

You know you've got one but cant find it.

I wonder if it will still work after all this time ... Bang

Oh no its gone rusty / filled with water / has critters living in it.

Why did i keep that? / What is it?

That was valuable once, now totally worthless and not worth using. (I just found a GAT5 in my microwave semiconductor drawer and some nuvistors)


Yep its clear-out time.  There's a lot in the last 4 categories, all soon to move to category 2

There are also a lot of great projects  coming back to the light

The joys of retirement!

Mark GM4ISM




On 19/08/2021 09:29, Chris Bartram G4DGU wrote:
Although I have been able to come to an understanding of waveguide operation and design techniques from a variety of sources, I've never really found a clearly comprehensible reference. Many books which claim to explain the subject seem more to want to show-off their author's extensive mathematical skills, than provide any form of clear explanation. I know that I'm not alone in finding this ...

Many times, I've noted references to the work of Theodore Moreno, and his 1944 book 'Microwave Transmission Design Data' but had never managed to find a copy for sale. This happened again while deciding on the best way to approach the design of a 68degree e-plane WG17 bend.

Needing some old books for for another research project (not related to engineering) I've discovered 'Abe Books' a French-owned multi-national grouping of secondhand booksellers (including many from the UK).  A quick look on the Abe web site showed several copies of Moreno's 1944 book (and later editions)at sensible prices, including a near mint softcover copy of the 1948 second edition published by Dover Books for not much more than UKP10. I bought that from a bookseller in Hamburg. It has now arrived, and the book has already been very useful in understanding the design of mitred e-plane waveguide bends.

With more thought, I've decided not to use a mitred bend (which can be made to work as well as a swept bend in a narrow-bandwidth application) as I discovered an additional treasury of WG17 parts in my garage! Amongst them are some easily modifiable swept WG17 e-plane bends ...

Chris

G4DGU









Virus-free. www.avg.com


Re: -- Was Waveguide Design - Book Recommendation

Paul G8AQA
 

Hi Mark,

I was recently looking at nuvistors for a very high dynamic range preamp to work in very close proximity to a transmitter on 50 MHz. The idea is not to blow up the device if 2 beams are pointing at each other on rare occasions. I haven't done the sums yet. Probably need a switchable attenuator after it to avoid overloading the RX. Playing with ideas at the moment.

73
Paul G8AQA

On 19/08/2021 09:54, Mark GM4ISM via groups.io wrote:
Sounds good Chris, hope to work you on 3cm EME sometime

I was going to suggest casting a swept bend, electroforming one on an aluminium shaped mandrel or machining one from a block with CNC.. all quite a bit of effort but fun?

Glad you found something..   A clear case of one of the major rules of the junk box.

You don't know what you've got till you find it again / I wish I knew I had that before I spent  loads of time / money on another.

You don't need it until after you throw it away.

You know you've got one but cant find it.

I wonder if it will still work after all this time ... Bang

Oh no its gone rusty / filled with water / has critters living in it.

Why did i keep that? / What is it?

That was valuable once, now totally worthless and not worth using. (I just found a GAT5 in my microwave semiconductor drawer and some nuvistors)


Yep its clear-out time.  There's a lot in the last 4 categories, all soon to move to category 2

There are also a lot of great projects  coming back to the light

The joys of retirement!

Mark GM4ISM




On 19/08/2021 09:29, Chris Bartram G4DGU wrote:
Although I have been able to come to an understanding of waveguide operation and design techniques from a variety of sources, I've never really found a clearly comprehensible reference. Many books which claim to explain the subject seem more to want to show-off their author's extensive mathematical skills, than provide any form of clear explanation. I know that I'm not alone in finding this ...

Many times, I've noted references to the work of Theodore Moreno, and his 1944 book 'Microwave Transmission Design Data' but had never managed to find a copy for sale. This happened again while deciding on the best way to approach the design of a 68degree e-plane WG17 bend.

Needing some old books for for another research project (not related to engineering) I've discovered 'Abe Books' a French-owned multi-national grouping of secondhand booksellers (including many from the UK).  A quick look on the Abe web site showed several copies of Moreno's 1944 book (and later editions)at sensible prices, including a near mint softcover copy of the 1948 second edition published by Dover Books for not much more than UKP10. I bought that from a bookseller in Hamburg. It has now arrived, and the book has already been very useful in understanding the design of mitred e-plane waveguide bends.

With more thought, I've decided not to use a mitred bend (which can be made to work as well as a swept bend in a narrow-bandwidth application) as I discovered an additional treasury of WG17 parts in my garage! Amongst them are some easily modifiable swept WG17 e-plane bends ...

Chris

G4DGU









Virus-free. www.avg.com


Re: -- Was Waveguide Design - Book Recommendation

Mark GM4ISM
 

Sounds good Chris, hope to work you on 3cm EME sometime

I was going to suggest casting a swept bend, electroforming one on an aluminium shaped mandrel or machining one from a block with CNC.. all quite a bit of effort but fun?

Glad you found something..   A clear case of one of the major rules of the junk box.

You don't know what you've got till you find it again / I wish I knew I had that before I spent  loads of time / money on another.

You don't need it until after you throw it away.

You know you've got one but cant find it.

I wonder if it will still work after all this time ... Bang

Oh no its gone rusty / filled with water / has critters living in it.

Why did i keep that? / What is it?

That was valuable once, now totally worthless and not worth using. (I just found a GAT5 in my microwave semiconductor drawer and some nuvistors)


Yep its clear-out time.  There's a lot in the last 4 categories, all soon to move to category 2

There are also a lot of great projects  coming back to the light

The joys of retirement!

Mark GM4ISM

On 19/08/2021 09:29, Chris Bartram G4DGU wrote:
Although I have been able to come to an understanding of waveguide operation and design techniques from a variety of sources, I've never really found a clearly comprehensible reference. Many books which claim to explain the subject seem more to want to show-off their author's extensive mathematical skills, than provide any form of clear explanation. I know that I'm not alone in finding this ...

Many times, I've noted references to the work of Theodore Moreno, and his 1944 book 'Microwave Transmission Design Data' but had never managed to find a copy for sale. This happened again while deciding on the best way to approach the design of a 68degree e-plane WG17 bend.

Needing some old books for for another research project (not related to engineering) I've discovered 'Abe Books' a French-owned multi-national grouping of secondhand booksellers (including many from the UK).  A quick look on the Abe web site showed several copies of Moreno's 1944 book (and later editions)at sensible prices, including a near mint softcover copy of the 1948 second edition published by Dover Books for not much more than UKP10. I bought that from a bookseller in Hamburg. It has now arrived, and the book has already been very useful in understanding the design of mitred e-plane waveguide bends.

With more thought, I've decided not to use a mitred bend (which can be made to work as well as a swept bend in a narrow-bandwidth application) as I discovered an additional treasury of WG17 parts in my garage! Amongst them are some easily modifiable swept WG17 e-plane bends ...

Chris

G4DGU




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

4801 - 4820 of 68481