Date   

Surplus crystal?

Chris G8BKE
 

Slightly off topic and a bit of a long shot but does anyone have a surplus crystal of frequency 14.4975MHz in their surplus stock that they are willing to part with?  HC18/U preferred but can accept HC25/U or HC6/U.
 
Please contact me off list at gmail,  g8bke23 etc
 
 
 
73 de Chris G8BKE
 


Re: Wessex F8401 amplifier #amplifier

G8FXB
 

Hi,

Unmodified they have a gain of about 20dB and NF around 4dB. I replaced all the FETs with MGF4919s on one and CE3512K2-C1 on another. I also converted the 1st stage to single ended. That reduced the NF to <1.4dB and increased the gain to 20-25dB. It also reduced the centre frequency. I didn't bother tweak it after that. 

The bias circuitry is quite fragile, physically and electrically. If you mod. one, be careful you don't damage it. It would be better to replace it with an alternative e.g. one of the Zetex bias controllers.

Regards,
Graham


Re: UKuG branded clothing

Murray Niman
 


Shameless plug and directly link:

https://www.microwavers.org/?accessories.htm 

- and nice UKuG badges still available too

    Murray G6JYB


Re: Last call for group buy of F6BVA QO-100 system PCBs etc

Colin Ranson
 

All,

 

Just a quick throw into the air.  I currently run a lashed up  up-converter from 432MHz to 2400MHz using a SKY-60LH mixer and an ADF4351A LO at 1968MHz – it drifts as it has a crap 25MHz reference crystal.  Some amplification up to 500mW to drive a 20w SG-Lab amp. It needs a lot of improvement. (stable reference <the RX LNB one> and sharp LO filter) Prime mover is an IC-706MK2g – I did use an SG-Lab transverter but a hell of a waste and a pain.

 

RX is down converter from LNB IF 739MHz  to 144MHz (FT480) – steady as Gibraltar. I have been having thoughts about changing the LO in this to 307MHz to give /RX IF of 432MHz to give full simplex on a non satelite equipped radio – ie the 706.

 

Anyone done anything similar ?

 

Regards to all,   Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: Neil Smith G4DBN
Sent: 14 March 2021 13:54
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Last call for group buy of F6BVA QO-100 system PCBs etc

 

As previously mentioned, I'm doing a group buy of PCB sets for the F6BVA
QO-100 up/down converter and MW7ic2725 PA.

This version of Michel's design is about making a simple standalone unit
for use over QO-100 without needing a computer or SDR dongle, and
without tying up the TX side of a 13cm transverter. Ideal for a go-box
with a 2m/70cm SSB rig and POTY-equipped dish.

There is already enough interest to do a group purchase of the
components. I will be providing some English-language construction
notes. The set of two PCBs is likely to cost around £40, perhaps a
little less if demand is high enough. Not sure of component cost yet,
but the Minicircuits mixer at £13 and MW7ic2725 at £50-ish are the only
expensive bits.

You'll need a local osc with two selectable frequencies. An SV1AFN or
even a Chinese ADF4350/51 would be good enough for QO-100 usage.

Sorry there isn't a converter-only option as the economics of fancy SHF
laminates and finishes mean we have to buy both boards, but you may be
able to find a home for the PA PCB if you don't need it.

For clarity, the older version was full-duplex, but this V3 is designed
to work with a simple half-duplex transceiver.  On 2m, you can use a
DF9NP LO using one of the control pins, but for the other bands (and
also 2m) you can use an SV1AFN or Chinese ADF4351 with a tx/rx
changeover flipping the frequency via a pin on the controller. I'll be
using an SV1AFN board. Not decided about the controller yet, might just
use an 8-pin PIC and PSU and TCXO on board, but that would just be
reinventing the SV1AFN controller. We'll be supporting this through the
IO group at https://groups.io/g/BVA-transverters-uk/message/356 which
you are welcome to join.

If you are interested, have a look at the document (in French) at
https://f6bva.pagesperso-orange.fr/Technique/Satellite/Station%20V3%20QO100%20complete.pdf

If you'd like to join a group purchase of the PCBs, with optional tin
box, milled aluminium PA box and full or part component set, please
email me direct to neil@... with title QO100 so I don't miss the
message!

I'll be finalising the order to send to Pierre-François in the next day
or two, but the ultimate cut-off will be when he submits the order to
the pcb fab. I don't expect there will be a second tranche.

Neil G4DBN




 


Last call for group buy of F6BVA QO-100 system PCBs etc

Neil Smith G4DBN
 

As previously mentioned, I'm doing a group buy of PCB sets for the F6BVA QO-100 up/down converter and MW7ic2725 PA.

This version of Michel's design is about making a simple standalone unit for use over QO-100 without needing a computer or SDR dongle, and without tying up the TX side of a 13cm transverter. Ideal for a go-box with a 2m/70cm SSB rig and POTY-equipped dish.

There is already enough interest to do a group purchase of the components. I will be providing some English-language construction notes. The set of two PCBs is likely to cost around £40, perhaps a little less if demand is high enough. Not sure of component cost yet, but the Minicircuits mixer at £13 and MW7ic2725 at £50-ish are the only expensive bits.

You'll need a local osc with two selectable frequencies. An SV1AFN or even a Chinese ADF4350/51 would be good enough for QO-100 usage.

Sorry there isn't a converter-only option as the economics of fancy SHF laminates and finishes mean we have to buy both boards, but you may be able to find a home for the PA PCB if you don't need it.

For clarity, the older version was full-duplex, but this V3 is designed to work with a simple half-duplex transceiver.  On 2m, you can use a DF9NP LO using one of the control pins, but for the other bands (and also 2m) you can use an SV1AFN or Chinese ADF4351 with a tx/rx changeover flipping the frequency via a pin on the controller. I'll be using an SV1AFN board. Not decided about the controller yet, might just use an 8-pin PIC and PSU and TCXO on board, but that would just be reinventing the SV1AFN controller. We'll be supporting this through the IO group at https://groups.io/g/BVA-transverters-uk/message/356 which you are welcome to join.

If you are interested, have a look at the document (in French) at https://f6bva.pagesperso-orange.fr/Technique/Satellite/Station%20V3%20QO100%20complete.pdf

If you'd like to join a group purchase of the PCBs, with optional tin box, milled aluminium PA box and full or part component set, please email me direct to neil@g4dbn.uk with title QO100 so I don't miss the message!

I'll be finalising the order to send to Pierre-François in the next day or two, but the ultimate cut-off will be when he submits the order to the pcb fab. I don't expect there will be a second tranche.

Neil G4DBN


Re: SHF Brolly (tks F1VL)

Neil Smith G4DBN
 

Just like me really. If a thing is worth doing, then it's worth over-doing.  The borderlines between radio engineering, jewellery-making and art sculpture narrow daily.

Neil G4DBN

On 14/03/2021 11:31, militaryoperator via groups.io wrote:
I think a chunky CNC milling machine would be a MUCH better investment though.  Then I could make stuff like Tauss does - lovely milled aluminium case for an ADALM Pluto with swoopy sides https://pbs.twimg.com/media/EwVVb5fVkAEyHk4?format=jpg&name=large


Looks like he's just trying to find things to do with that nice big CNC machine! Slightly overkill? 

Ben


Re: SHF Brolly (tks F1VL)

militaryoperator
 

I think a chunky CNC milling machine would be a MUCH better investment though.  Then I could make stuff like Tauss does - lovely milled aluminium case for an ADALM Pluto with swoopy sides https://pbs.twimg.com/media/EwVVb5fVkAEyHk4?format=jpg&name=large


Looks like he's just trying to find things to do with that nice big CNC machine! Slightly overkill? 

Ben


Re: SHF Brolly (tks F1VL)

Neil Smith G4DBN
 

On 14/03/2021 10:25, militaryoperator via groups.io wrote:

Apparently Neil, $1780 for 1.8 dish and 23m feed shipped to Uk. $280 is for post so $1500 for goods. 

I know there's a bit of engineering in the tensioning system, though just like a brolly, but seems a lot, £1077. 

Mind you, on another FB page someone was saying they just paid £120 for a premade Windom aerial! and that's just a bit of wire. Then there's that bit of wire in a long thin bag that you can buy for £90 odd and you stick a plastic pole up the bag center to make a verticle. 

I'm in the wrong game, hi, well not any game these days. 

I don't mind folks making a living out of selling stuff. If they can find customers willing to pay, then go for it.  We should make QSLs into Non-Fungible Tokens and start a secondary market in them. Hamcoin sounds a good plan as well.

I can see the attraction of that antenna for folks who can't operate from home or only have a tiny space, and who are working full time and don't have the facilities to make stuff. I prefer to waste my pocket-money on machine tools and testgear so I can make stuff, but I know a lot of amateurs who get huge pleasure from buying nice things and operating them.  I'm just one of those hams who doesn't actually enjoy talking to strangers on the radio, so making and testing and modifying stuff is what I like to do.

Still, if I didn't have a motorhome and trailer for /P stuff, I could see myself saving up the pennies for one of these brollies. Bit of a bugger trying to get any other 1.8m dish in a saloon car, especially one without a towbar.

I think a chunky CNC milling machine would be a MUCH better investment though.  Then I could make stuff like Tauss does - lovely milled aluminium case for an ADALM Pluto with swoopy sides https://pbs.twimg.com/media/EwVVb5fVkAEyHk4?format=jpg&name=large

Neil G4DBN




Wessex F8401 amplifier #amplifier

am.andrej@...
 

Hi,

I'm looking for any information about Wessex F8401 amplifier. 7.85GHz-8.45GHz
Power supply range, NF and gain?
Maybe useful for DSN system as LNA ..need some info before buy it from allegro.

thanks info

73 de Andrej


MGM Beacon History

Andy G4JNT
 

Would I be right in thinking GB3VHF was the first permanent beacon to adopt any of the WSJT modes?    It certainly was in the UK, coz, ahem, yours-truly built the driver for it.

That was in 2005 and initially the mode was to have been JT44, then changed to JT65 as that mode had just appeared.

What I'm wondering, is if there were any others in the World that were earlier?


Re: SHF Brolly (tks F1VL)

militaryoperator
 

Subject: Re: [UKMicrowaves] SHF Brolly (tks F1VL)

I guess approximately $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
Neil
On 13/03/2021 20:49, militaryoperator via groups.io wrote:
No prices on their website !!

Ben
---------------------------

Apparently Neil, $1780 for 1.8 dish and 23m feed shipped to Uk. $280 is for post so $1500 for goods. 

I know there's a bit of engineering in the tensioning system, though just like a brolly, but seems a lot, £1077. 

Mind you, on another FB page someone was saying they just paid £120 for a premade Windom aerial! and that's just a bit of wire. Then there's that bit of wire in a long thin bag that you can buy for £90 odd and you stick a plastic pole up the bag center to make a verticle. 

I'm in the wrong game, hi, well not any game these days. 

Ben


Re: UKuG branded clothing

John E. Beech
 

"polo shorts" are no good to me - I haven't got a horse! Unless they are swimming trunks for the other polo game. I
guess you mean "shirts", but spell checkers don't high-light those sort of mistakes

-------Original Message-------
From: Chris G0FDZ <chris@g0fdz.com>
To: UK microwaves <UKMicrowaves@groups.io>
Subject: [UKMicrowaves] UKuG branded clothing
Sent: Mar 14 '21 07:12

Hi folks

Just a  reminder that the details of how to obtain the UKuG branded
clothing (polo shorts and fleeces) can now be found at the bottom of the
front page of the UKuG website in the 'Badges, Clothing and Accessories'
section.

Regards

Chris G0FDZ


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







UKuG branded clothing

Chris G0FDZ
 

Hi folks

Just a  reminder that the details of how to obtain the UKuG branded clothing (polo shorts and fleeces) can now be found at the bottom of the front page of the UKuG website in the 'Badges, Clothing and Accessories' section.

Regards

Chris G0FDZ


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


Re: oh er

Stefan
 

Hi Mike and Neil

I think they are using 250mW on 80Ghz into a VDI highpower tripler with an efficiency of 6 to 8% you can achieve the stated 20mW for TX and
for RX they prob used a x2 subharmonic mixer with 120ghz injection and around 3 to 5mw LO.
Like everyone else i am dreaming of ever to own a commercial mixer multiplier for 241Ghz, till then I have to be happy with -30dbm TX power
in a mixer based system or -20dbm if the diode is setup as a multiplier.

Stefan VK4CSD

----- Original Message -----
From: "Neil Smith G4DBN" <neil@g4dbn.uk>
To: <UKMicrowaves@groups.io>
Sent: Sunday, March 14, 2021 8:02 AM
Subject: Re: [UKMicrowaves] oh er


Ah, thanks Mike, I see the W-band mixer diodes are $200 each with min
order $2k per part type. Multipliers look nice, but I guess unfeasibly
expensive for amateurs. 6-8 % efficiency at 20-50 mW in for the doublers
and a little less efficiency for the triplers, but up to 100 mW input.
I guess we will have to continue dreaming about such things unless the
lads have tapped into a secret lode of multiplier goodness.

https://www.vadiodes.com/en/frequency-multipliers/?id=166

https://www.vadiodes.com/en/products/w-and-g-band

Neil G4DBN

On 13/03/2021 21:47, Mike Lavelle K6ML wrote:
Virgina Diodes GaAs varactor multipliers


Re: oh er

Neil Smith G4DBN
 

Ah, thanks Mike, I see the W-band mixer diodes are $200 each with min order $2k per part type. Multipliers look nice, but I guess unfeasibly expensive for amateurs. 6-8 % efficiency at 20-50 mW in for the doublers and a little less efficiency for the triplers, but up to 100 mW input.  I guess we will have to continue dreaming about such things unless the lads have tapped into a secret lode of multiplier goodness.

https://www.vadiodes.com/en/frequency-multipliers/?id=166

https://www.vadiodes.com/en/products/w-and-g-band

Neil G4DBN

On 13/03/2021 21:47, Mike Lavelle K6ML wrote:
Virgina Diodes GaAs varactor multipliers


Re: oh er

Dave G8KHU
 

"Celsius, not Celcius."

Very true, my apologies to Anders Celsius. I'm getting too dependent (or dependant - let's not go there) on spell checkers.

My physics teacher used to dock marks for incorrectly spelt units, I'm slipping, sorry Sir.

Dave


Re: oh er

Mike Lavelle K6ML
 

Hi, Neil ...

I believe that they get their 20 mW QRO using Virgina Diodes GaAs varactor multipliers.
These parts are used in the LO chains of EHF radiotelescopes.

73,

Mike K6ML


Re: oh er

Simon Brown
 

I believe that °C is the correct abbreviation for Celsius (which is measured in degrees). The abbreviation of Kelvin is K.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> On Behalf Of Andy G4JNT
Sent: 13 March 2021 16:53
To: UK Microwaves groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] oh er

 

If you want to be really pedantic, "... temperature was -1 ° C"  should read  "... temperature was -1C"

C is the unit of temperature,  no degree sign

 

 

 

On Sat, 13 Mar 2021 at 16:29, militaryoperator via groups.io <Military1944=aol.com@groups.io> wrote:

241Ghz

 

Distance: 63,987 km

WOW !!!!!!!!!!!!!!!!!!

 

 

 

er um. After Brexit I thought we would sort out the . and , in measuring?

 

Ben

 

-----Original Message-----
From: Scatterpoint@groups.io Notification <noreply@groups.io>
To: Scatterpoint@groups.io <Scatterpoint@groups.io>
Sent: Sat, 13 Mar 2021 16:20
Subject: [Scatterpoint] File /SP2102-A4-Issue2.pdf uploaded #file-notice

The following files have been uploaded to the Files area of the Scatterpoint@groups.io group.

By: Roger Ray <g8cub@...>

Description:
February 2021 Scatterpoint is published Updated version with apologies to Barry G8AGN for errors in his article


Re: oh er

Wilko
 

Celsius, not Celcius.

SI would afaik absolute temperature in Kelvin

Wilko
PA1WBU


Re: oh er

Dave G8KHU
 

I've only ever known Kelvin as K but evidently it was degrees Kelvin ( °K ) until 1968, interesting how things change :)

To drift back slightly more onto topic I'm with Neil, I to would like to know about how they realised 20 mW

Dave

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