PCB delivery


Robin Szemeti - G1YFG
 

I have to say the PGA103+ is a most excellent device ... and your PGA144 seems to perform very well.

As I had a strip of pHEMT these were just a bit of fun to see how they turned out, they didn't take long to draw up and I was bored, I'll see how they turn out.


On Fri, 8 Jan 2021 at 20:27, SAM JEWELL via groups.io <jewell=btinternet.com@groups.io> wrote:
Just to clarify the difference between the 2m PGA144 and the VLNA preamplifiers.
The PGA144 preamp incorporates both a notch filter at 98MHz cf as well as a carefully designed 130MHz HPF. The combined HPF and notch together create a small but significant reduction in 144MHz input circuit loss, hence improving the noise figure at 144MHz. This unusual, and possibly unique, arrangement was suggested by G4SWX some years ago during development of the PGA144. It follows on from some older low loss HPF input work by DJ7VY, LA8AK and others.
The low Q bandpass output filter is designed to not only enhance gain at 144MHz but also to roll off gain above the band.
The variable output attenuator allows gain setting as required.
The PGA144 is not a high gain, wideband, preamplifier, like the VLNA designs, which are meant for EME where second stage contribution needs to be minimised together with the lowest loss input matching arrangement.
The dynamic range of the PGA144 is way above most earlier GaAs mesFet and HEMT preamplifiers. You need a pretty good following receiver to take advantage of the PGA144 dynamic range!

73 de Sam,  G4DDK



On 8 d 130MHz HPFJan 2021, at 18:04, David Redman <nt I@...> wrote:
 Years ago

Yes Sam's preamps are excellent for low noise and high gain, just what you need for dish mounted preamps.
D
Dedending on da to be minimisedyour local RF signal levels 50 to 1600MHz for terrestrial use and depending on your levels of Band 2 FM, 220MHz ish DAB, UHF digital TV and then cell phoness gain setting plus reminent vhf / uhf pmr plus pagers  you may need a decent BPF ahead of the pre-amp.
I use Sam's preamps on 2m, 23cms and 9cms EME and they are excellent but be aware for tropo use they are relatively wideband input. 

Dave
G4IDR 



--
Robin Szemeti - G1YFG


SAM JEWELL
 

Just to clarify the difference between the 2m PGA144 and the VLNA preamplifiers.
The PGA144 preamp incorporates both a notch filter at 98MHz cf as well as a carefully designed 130MHz HPF. The combined HPF and notch together create a small but significant reduction in 144MHz input circuit loss, hence improving the noise figure at 144MHz. This unusual, and possibly unique, arrangement was suggested by G4SWX some years ago during development of the PGA144. It follows on from some older low loss HPF input work by DJ7VY, LA8AK and others.
The low Q bandpass output filter is designed to not only enhance gain at 144MHz but also to roll off gain above the band.
The variable output attenuator allows gain setting as required.
The PGA144 is not a high gain, wideband, preamplifier, like the VLNA designs, which are meant for EME where second stage contribution needs to be minimised together with the lowest loss input matching arrangement.
The dynamic range of the PGA144 is way above most earlier GaAs mesFet and HEMT preamplifiers. You need a pretty good following receiver to take advantage of the PGA144 dynamic range!

73 de Sam,  G4DDK



On 8 d 130MHz HPFJan 2021, at 18:04, David Redman <nt I@...> wrote:
 Years ago

Yes Sam's preamps are excellent for low noise and high gain, just what you need for dish mounted preamps.
D
Dedending on da to be minimisedyour local RF signal levels 50 to 1600MHz for terrestrial use and depending on your levels of Band 2 FM, 220MHz ish DAB, UHF digital TV and then cell phoness gain setting plus reminent vhf / uhf pmr plus pagers  you may need a decent BPF ahead of the pre-amp.
I use Sam's preamps on 2m, 23cms and 9cms EME and they are excellent but be aware for tropo use they are relatively wideband input. 

Dave
G4IDR 



David Redman
 

Yes Sam's preamps are excellent for low noise and high gain, just what you need for dish mounted preamps.

Dedending on your local RF signal levels 50 to 1600MHz for terrestrial use and depending on your levels of Band 2 FM, 220MHz ish DAB, UHF digital TV and then cell phones plus reminent vhf / uhf pmr plus pagers  you may need a decent BPF ahead of the pre-amp.
I use Sam's preamps on 2m, 23cms and 9cms EME and they are excellent but be aware for tropo use they are relatively wideband input. 

Dave
G4IDR 




On Fri, 8 Jan 2021, 17:41 Robin Szemeti - G1YFG, <robin@...> wrote:
Hi Martin,

Sam Jewell's preamps are excellent on 23cm, but you do need to put an attenuator in the output for terrestrial use if you are intending to do contest from a reasonable location, or it does tend to get a bit loud!  These pre's were just a bit of fun really, the 70cm one has a self-adjusting bias ... the 2m one is a little more conventional, with a pot for the bias.
image.png

image.png


Off topic ...

I'm also planning to use OpenCPN on the boat, when and if I can get back to it, as it is in Wales.  I have shiny new B&G hull sensors and wind instrument,  hoping to drop the NMEA2000 outputs into SignalK and pick them up as needed for the plotters. I'll still keep Navionics on a tablet though, as that works really well.  I'm looking forward to integrating the AIS into that.

I understand the problems of the Helford river, we are in the Menai Strait so have all the fun of navigating the currents and shallows with either The Swellies or Caernarfon Bar to cross to get out.  The boat did not make it into the water last year due to the lockdown in Wales we coudl not get access to finish the tasks and it is locked down again. hopefully this year will be better, as last year was just a complete money pit for a toy I could not use ... my other toy has wings,  that was even worse.


--
Robin Szemeti - G1YFG


Robin Szemeti - G1YFG
 

Hi Martin,

Sam Jewell's preamps are excellent on 23cm, but you do need to put an attenuator in the output for terrestrial use if you are intending to do contest from a reasonable location, or it does tend to get a bit loud!  These pre's were just a bit of fun really, the 70cm one has a self-adjusting bias ... the 2m one is a little more conventional, with a pot for the bias.
image.png

image.png


Off topic ...

I'm also planning to use OpenCPN on the boat, when and if I can get back to it, as it is in Wales.  I have shiny new B&G hull sensors and wind instrument,  hoping to drop the NMEA2000 outputs into SignalK and pick them up as needed for the plotters. I'll still keep Navionics on a tablet though, as that works really well.  I'm looking forward to integrating the AIS into that.

I understand the problems of the Helford river, we are in the Menai Strait so have all the fun of navigating the currents and shallows with either The Swellies or Caernarfon Bar to cross to get out.  The boat did not make it into the water last year due to the lockdown in Wales we coudl not get access to finish the tasks and it is locked down again. hopefully this year will be better, as last year was just a complete money pit for a toy I could not use ... my other toy has wings,  that was even worse.


--
Robin Szemeti - G1YFG


Paul Randall G3NJV
 

Haha, probably not.  
Got a new aerial group to go up for 2,70 & 23, only modest,  for 24/7 all weather use so the pre-amps sound ideal, just need to source one for 23cm. Was looking around wondering what to get. 

You sound super productive,  all those projects.  Hopefully you'll get the boat in this year.  Our yard has locked us out again,  hopefully lifted by april?

I found a very economical German Class B  AIS on ebay - bit of a last minute change as I had only planned to fit a Rx. The now unwanted rx is being used as a propagation monitor feeding the sentences into a nmeatools nmea to Wi-Fi box. Opencpn base map is good enough to show me what vhf is doing on my phone. 

Same setep on the boat I can have as many "no wires" chartplotters aboard as I want, works really well and a super feature is that i can grab kap ? Charts taken from Google earth satellite images that overlay vector cmap charts - super accurate you can calibrate the commercial charts and super useful - real  images of anchorages, mooring buoys in harbours, marinas etc and by a great stroke of luck,  the images of the Helford river were taken at low tide so show the narrow tortuous deep channel thru the mud we have to negociate to get to/ from the boatyard every year. Clearance less that 0.3m in places so have to position the boat within a metre or so. Helps a lot but we invariably go aground anyway haha.   

Happy New year Robin
Paul



Sent from my Galaxy



-------- Original message --------
From: Robin Szemeti - G1YFG <robin@...>
Date: 08/01/2021 13:28 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] PCB delivery

Certainly!  I'll build up a couple to check them .. they are more a "contest" HA8ET style LNA than a high gain EME style one. They feature a suitable "notch" on the input for 432 or 144, an output filter for 432 or 144 and a protection relay on the input to try and preserve the LNA when sitting on the end of a relay that may have QRO on the transmit port, a pot is provided on the output so you can set it for just enough gain ... they should fit the standard tinplate boxes.

Let me build them up and get back to you, I have cocked them up, you never know ;)

On Fri, 8 Jan 2021 at 12:48, Paul Randall G3NJV <paulfrandall@...> wrote:
Hi Robin, any lna boards going spare?
Hope you are well
Paul



Sent from my Galaxy



-------- Original message --------
From: Robin Szemeti - G1YFG <robin@...>
Date: 08/01/2021 12:25 (GMT+00:00)
Subject: [UKMicrowaves] PCB delivery

Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG


--
Robin Szemeti - G1YFG


Robin Szemeti - G1YFG
 

Yes it is, google "peterantypas AIS" .. I have 5 boards here and only really need one, and an SMT paste stencil ... I may even have spares of the two "hard to get" chips, the SiRadio devices and the skytronics RF switch .. ping me offlist, it is radio related, but I doubt the uWave lot want to hear us prattling on about boaty digital comms.

On Fri, 8 Jan 2021 at 14:17, Martin Phillips G4CIO <martin@...> wrote:
<OT> Hi Robin, is the AIS tcvr a published design? I've been thinking for a while that we could do with one on one of our boats...</OT>

Martin/

On 8/1/21 12:25 PM, Robin Szemeti - G1YFG wrote:
Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG



--
Robin Szemeti - G1YFG


Martin Phillips G4CIO
 

<OT> Hi Robin, is the AIS tcvr a published design? I've been thinking for a while that we could do with one on one of our boats...</OT>

Martin/

On 8/1/21 12:25 PM, Robin Szemeti - G1YFG wrote:
Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG



Robin Szemeti - G1YFG
 

Certainly!  I'll build up a couple to check them .. they are more a "contest" HA8ET style LNA than a high gain EME style one. They feature a suitable "notch" on the input for 432 or 144, an output filter for 432 or 144 and a protection relay on the input to try and preserve the LNA when sitting on the end of a relay that may have QRO on the transmit port, a pot is provided on the output so you can set it for just enough gain ... they should fit the standard tinplate boxes.

Let me build them up and get back to you, I have cocked them up, you never know ;)


On Fri, 8 Jan 2021 at 12:48, Paul Randall G3NJV <paulfrandall@...> wrote:
Hi Robin, any lna boards going spare?
Hope you are well
Paul



Sent from my Galaxy



-------- Original message --------
From: Robin Szemeti - G1YFG <robin@...>
Date: 08/01/2021 12:25 (GMT+00:00)
Subject: [UKMicrowaves] PCB delivery

Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG


--
Robin Szemeti - G1YFG


Paul Randall G3NJV
 

Hi Robin, any lna boards going spare?
Hope you are well
Paul



Sent from my Galaxy



-------- Original message --------
From: Robin Szemeti - G1YFG <robin@...>
Date: 08/01/2021 12:25 (GMT+00:00)
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] PCB delivery

Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG


Robin Szemeti - G1YFG
 

Nice delivery of pcbs today, the 9cm transverter is the one that I'm looking forward to building up.

There is another batch of CANFI noise heads, but my pick and place is in bits at the moment,  i 'll try and sort that, and mount the components, otherwise they'll have to go out as kits.

There are some 2m and 70cm LNA, some mmic boards for a friend and an AIS transceiver for my boat. Plenty of RF  projects to keep me busy.

--
Robin Szemeti - G1YFG