Date   

Re: VK3CV 30THz full system demonstration.

f1ghb
 

Hello,

Pyroelectric Thermometer can be also used as millimeterwave ( 122GHz.. ) detector.

See :

http://highfrequencyelectronics.com/Mar09/HFE0309_DesignNotes.pdf

In the past I have used the MELEXIS MLX90247 with success in this application

73s Eric



Le 08/01/2021 08:42, Barry Chambers a écrit :

Tim

many thanks

Barry, G8AGN


On 08/01/2021 00:55, Tim, VK2XAX wrote:

Andrew says...

"RX is based on a chip from Melexis, the MLX90614 which operates between approx 5 -14um.

I'm in the process of getting a detailed article written now."

cheers
Tim

On 7/1/21 7:34 pm, Barry Chambers wrote:
Tim

fascinating demo. What is the receive sensor please?

73 Barry, G8AGN


-- 
VK2XAX : QF56if : ITU59 : CQ30 : BMARC : WIA
-- 
73
Barry, G8AGN


Re: VK3CV 30THz full system demonstration.

G1BVI-Nick
 

I wonder how the receiver would respond when pointed at the sun?
might be a way of detecting solar flares perhaps???


Re: Avoiding courier customs service fees

Robin Szemeti - G1YFG
 

I've never had a problem with JLC PCB and VAT/Duty, I order from them regularly, both for work and amateur use (not only because of price, but mostly because of speed and quality) and they have always been absolutely correct on their customs declarations ... the additional small charge on top of the VAT etc is not an issue for me.

the eBay "global shipping program" allows an item bought in say, the USA to be sent from an eBay USA warehouse in bulk, correctly declared and duty/VAT paid up front ... so that works well.

For genuine amateur to amateur sales, it should not be an issue. The new document states:

>quote

Non-business sales

Sales made by persons who are not in business are outside the scope of these measures. This includes gifts and consignments sent from consumer to consumer. Guidance on whether an activity is a business activity or not for VAT purposes can be found in the Non-business manual

> end quote

so there should not be any VAT/duty on genuine consumer to consumer sales entering the UK from either the EU or anywhere else.


On Sat, 9 Jan 2021 at 10:08, Mike Willis <willis.mj@...> wrote:
Back on topic hopefully. I have never objected to paying duty and VAT but I do strongly object to paying £8 to £20 on top of that duty to the courier I already paid handsomely to deliver it in order to collect that duty. Often this charge is many times the amount of duty/VAT collected. Last week I had a charge of £8 on £4 VAT. There  is no option to appeal the fee and in the case of the post office it adds several days of delay. This £8 fee will now apply even to items costing £1, in order to collect 20p.

Unlike avoiding duty, avoiding these charges is not illegal. It is common sense.

Digikey, JLCPCB, Mouser allow pre-payment of the duty so this doesn't happen. Looks like Amazon and Ebay might be doing something similar. How do we arrange for a similar process to buy/sell something from/to another amateur? In a similar way to Parcels-To-Go can greatly reduce shipping costs maybe someone has a solution in the works.


--
Mike G0MJW


--
Robin Szemeti - G1YFG


Bell Hill Beacons

Andy G4JNT
 

No,  Don't panic - they're all running OK :-)

Just posting to say Thank You to those who have made donations over the last few months towards the upkeep of these bacons - you know who you are.

If you regularly monitor these beacons from Bell Hill in Dorset,  LOC. IO80UU59  , then please consider making a donation to their upkeep and site rental.  With rally stands non-operational nowadays, the easiest way is to go to http://www.g4jnt.com/SCRBG/donate/index.html and hit the big yellow button.  Or a cheque to me QTHR.

For info.   The beacons are:
  GB3SCS 2320.905    JT4G
  GB3SCF 3400.905,   JT65C
  GB3SCC 5760.905,   JT4G
  GB3SCX 10368.905  JT4G
  GB3SCK 24048.905  JT4G
  GB3SCQ 47088.905 

All except the two highest frequency ones are GPS Locked to within a few Hz of nominal.



Re: Slew drives from China

Mike Willis
 

Strangely the supplier I used last time is offering a 3% discount on orders in January.

Sun-Xuzhou Wanda slewing bearing Company. Easy to deal with and quick delivery via DHL. They even have a youtube channel where they shod how the manufacture them. Overkill for a 1.2m dish, even the little ones, but cheaper than a rotator.

--
Mike G0MJW


Avoiding courier customs service fees

Mike Willis
 

Back on topic hopefully. I have never objected to paying duty and VAT but I do strongly object to paying £8 to £20 on top of that duty to the courier I already paid handsomely to deliver it in order to collect that duty. Often this charge is many times the amount of duty/VAT collected. Last week I had a charge of £8 on £4 VAT. There  is no option to appeal the fee and in the case of the post office it adds several days of delay. This £8 fee will now apply even to items costing £1, in order to collect 20p.

Unlike avoiding duty, avoiding these charges is not illegal. It is common sense.

Digikey, JLCPCB, Mouser allow pre-payment of the duty so this doesn't happen. Looks like Amazon and Ebay might be doing something similar. How do we arrange for a similar process to buy/sell something from/to another amateur? In a similar way to Parcels-To-Go can greatly reduce shipping costs maybe someone has a solution in the works.


--
Mike G0MJW


Re: MMIC's

Andy G4JNT
 

If you want a filter at 2.3/2.4GHz worth trying a piece of WG15 or WG14 as a comb line.   Use long 2BA/M4 screws as resonators across the guide,  screwed into the narrow face and work out the spacing and coupling/transformers using an online calculator / guessing / experimenting. 

WG16 'can' be made to work, but the spacing from the far wall is so minute, tuning is near impossible.   Having said that, I have done it in WG16 for a couple of two section resonators - good enough for 144MHz IF -  and the filter has remained on frequency for years, but initial setting up was a nightmare.



On Sat, 9 Jan 2021 at 09:27, Colin Ranson <g8lbs@...> wrote:

Thanks Geoff,

 

Info appreciated.  I will try 28mm.

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 22:57
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Yes i did use a TOKO 2 pole filter for 1242 MHz and used a 28 mm pipe cap for X2.

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 19:59:01 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Just one last thing Geoff,   did you use a 2 pole TOKO filter at 1242MHz or did you by-pass ? Maybe no need for a filter in that position if you are multiplying ?

 

Regards

 

Colin

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 17:47
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 

 

 


Re: MMIC's

Colin Ranson
 

Thanks Geoff,

 

Info appreciated.  I will try 28mm.

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 22:57
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Yes i did use a TOKO 2 pole filter for 1242 MHz and used a 28 mm pipe cap for X2.

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 19:59:01 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Just one last thing Geoff,   did you use a 2 pole TOKO filter at 1242MHz or did you by-pass ? Maybe no need for a filter in that position if you are multiplying ?

 

Regards

 

Colin

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 17:47
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 

 

 


Re: 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


Re: VAT ... it looks like it's going to be difficult.

Robin Szemeti - G1YFG
 

I suggest we leave it there, if anyone wants to continue the discussion, kindly mail be off list.

On Fri, 8 Jan 2021 at 21:03, G8DQX list <list@...> wrote:
Dear Robin S.,

perhaps the rest of us will not be as sadly disappointed as one assumes
that you will be when it is pointed out, forcefully, that fraud is not
unique to any race, country, or trading arrangement. The UK has plenty
of VAT fraudsters of its own, as has the EU/EEA. Given the example of
Enron, and there are plenty of others, it seems that the USA has no lack
of fraudsters either.

To single out China is, on the face of it, racist.

Robin, G8DQX

On 07/01/2021 18:30, Robin Szemeti - G1YFG wrote:
> No problem with that, as others have said, there is no place for
> racism here or anywhere else, but if you are expecting me to refrain
> from criticising the extensive VAT and customs fraud committed by
> traders from the Republic of China, I'm afraid you are going to be
> sadly disappointed.






--
Robin Szemeti - G1YFG


Re: MMIC's

geoffrey pike
 

Hi Colin,
Yes i did use a TOKO 2 pole filter for 1242 MHz and used a 28 mm pipe cap for X2.
cheers
Geoff
GI0GDP

On Friday, 8 January 2021, 19:59:01 GMT, Colin Ranson <g8lbs@...> wrote:


Just one last thing Geoff,   did you use a 2 pole TOKO filter at 1242MHz or did you by-pass ? Maybe no need for a filter in that position if you are multiplying ?

 

Regards

 

Colin

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 17:47
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 

 


Re: MKU 13 G3 Schematic

Conrad, PA5Y
 

Thanks Geoff, desoldering is no problem. I will get a few just in case.

 

Conrad

 

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of geoffrey pike via groups.io
Sent: 08 January 2021 18:59
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MKU 13 G3 Schematic

 

Hi Conrad,

The Franco PCBs SU-02 have 4 on each, but you will need to de solder them

Geoff

GI0GDP

 

On Friday, 8 January 2021, 09:24:06 GMT, Conrad, PA5Y <g0ruz@...> wrote:

 

 

Yes the G2 schematic is available from the Kuhne archives, I suppose what I should have said was. I have the G2 schematic, is the front end the same for the G3? I have a G3. I suspect that the front end is indeed the sane. Which leads me to the next question. Where can I get a few NE32584Cs?

 

73

 

Conrad PA5Y

 

 


From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of DF6NA Rainer via groups.io <df6na@...>
Sent: 08 January 2021 07:04
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] MKU 13 G3 Schematic

 


It's correct !!!

Am 07.01.2021 um 23:40 schrieb Graham G3VKV via groups.io:

    DB6NT 13cms G2 front end FET is an NE32584C

                                                    Graham G3VKV

 


Re: VAT ... it looks like it's going to be difficult.

G8DQX list
 

Dear Robin S.,

perhaps the rest of us will not be as sadly disappointed as one assumes that you will be when it is pointed out, forcefully, that fraud is not unique to any race, country, or trading arrangement. The UK has plenty of VAT fraudsters of its own, as has the EU/EEA. Given the example of Enron, and there are plenty of others, it seems that the USA has no lack of fraudsters either.

To single out China is, on the face of it, racist.

Robin, G8DQX

On 07/01/2021 18:30, Robin Szemeti - G1YFG wrote:
No problem with that, as others have said, there is no place for racism here or anywhere else, but if you are expecting me to refrain from criticising the extensive VAT and customs fraud committed by traders from the Republic of China, I'm afraid you are going to be sadly disappointed.


Re: PCB delivery

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 



Re: MMIC's

Colin Ranson
 

Just one last thing Geoff,   did you use a 2 pole TOKO filter at 1242MHz or did you by-pass ? Maybe no need for a filter in that position if you are multiplying ?

 

Regards

 

Colin

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 17:47
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 

 


Re: MMIC's

Colin Ranson
 

Hi Geoff,

 

Ha !   waiting for a couple of 35mm (or so) pipe caps to make a 2556MHz filter. I hope to align these using a noise source and my SAA-N2 VNA.  Wonder what size caps you used ? I have some 28mm here so it might be a toss-up between the two sizes.

 

Glad to see people on the RF make !

 

73’s   Colin.

 

Sent from Mail for Windows 10

 

From: geoffrey pike via groups.io
Sent: 08 January 2021 17:47
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] MMIC's

 

Hi Colin,

Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 

cheers

Geoff

GI0GDP

 

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:

 

 

Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 

 


Re: PCB delivery

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


Re: MKU 13 G3 Schematic

geoffrey pike
 

Hi Conrad,
The Franco PCBs SU-02 have 4 on each, but you will need to de solder them
Geoff
GI0GDP

On Friday, 8 January 2021, 09:24:06 GMT, Conrad, PA5Y <g0ruz@...> wrote:


Yes the G2 schematic is available from the Kuhne archives, I suppose what I should have said was. I have the G2 schematic, is the front end the same for the G3? I have a G3. I suspect that the front end is indeed the sane. Which leads me to the next question. Where can I get a few NE32584Cs?

73

Conrad PA5Y



From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of DF6NA Rainer via groups.io <df6na@...>
Sent: 08 January 2021 07:04
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] MKU 13 G3 Schematic
 

It's correct !!!

Am 07.01.2021 um 23:40 schrieb Graham G3VKV via groups.io:
    DB6NT 13cms G2 front end FET is an NE32584C

                                                    Graham G3VKV


Re: MMIC's

geoffrey pike
 

Hi Colin,
Doing somethimg similar just to do something!, anyway DDK microwave source pcb 103.5 MHz Xtal output at 1242 MHz (this has needed a job so iam using it), this drives a MCL VNA-25 mmic at about 4dBm this then goes into a pipe cap filter at 2484 MHz, then another VNA-25 with -8dB ahead of it to give 14dBm at 2484 Mhz then into the W1MHZ quadrupler for about 8 dBm out at 9936 MHz to drive a Minicircuits mixer and mix with 432 MHz. The VNA-25 is a small outline 8 pin DIL device so a bit different to usuall mmic. About 14 dB gain and 17dBm out at 2,5 GHz. 
cheers
Geoff
GI0GDP

On Friday, 8 January 2021, 14:03:52 GMT, Colin Ranson <g8lbs@...> wrote:


Hi all,

 

I have repurposed a DDK 2008 L band source from 96MHz to 106.5MHz with an output of 1278MHz.  The original was extended to include a PGA103+ to bump up the output to feed a high level mixer.   

 

 

Thinks ?  could I use this MMIC as a doubler to 2256MHz ? I understand from texts that it has to be operated in a non-linear fashion)  At the moment its biased to 3.5v and I have removed a level determining attenuator so I am hitting the MMIC quite hard. I am detecting very little at 2556MHz at the moment. (not enough to drive my Qualcom x 4 multiplier to 10.224GHz)

 

Can anyone give me a ballpark figure to set the bias to please ? And is this likely to work well enough ? I have not tried this method before so hopefully with enough 2256MHz I will include a ‘stop-end’ filter and enough gain to give me 3dbm at the Qualcom Mult input. Getting the 10dbm output (after filtering) for the mixer(s) will be another matter.

 

Best regards to all, keep those soldering irons hot !

 

Regards, Colin de G8LBS.

 

 

 

Sent from Mail for Windows 10

 


Re: PCB delivery

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

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