Date   

Re: EVO Filter construction

g4cch_1
 

I have taps for: 0, 2, 4 , 6 and 8BA
Will probably use 2 or 0BA brass screws and nuts on my next filter attempt.

Just waiting for WG14 now.

Will scale dims from Andy G4JNT's 3.4GHz article, based on ratio of waveguide dimensions. 

If this is not the way to do it, then please let me know...

Thanks and 73
Howard,  G4CCH 


Re: EVO Filter construction

Paul G8AQA
 

Very sad you don't have any BA taps and dies. I have 0BA to at least 12BA with nuts and screws to suit.
🙁
Paul G8AQA

On 30/01/2021 16:27, Neil Smith G4DBN wrote:

After Andy mentioned this type of filter some time last year, I had a go at making some. Because of my metalbashing addition and for general bling (and maybe performance), I made the tuning screws from Tellurium Copper, with knurled heads for easy finger-tweaking.  I might still have a few of the tuning screws kicking about if anyone wants some to try.  I cut the threads deliberately oversize to improve the fit, and made slightly thicker than standard brass locknuts, although the pic shows a stainless one.  I also made up some solder-in threaded collars to give a longer thread engagement, but that is more faff than just drilling and tapping the holes.  I used a thread-rolling tap rather than a normal cutting tap for the copper waveguide.  Whether they work any better than brass screws, I didn't have the energy left to investigate, but I had a pile of machine-shop fun, and that's an end in itself. These are M3 x 0.5 with 9mm head and 2.3mm plain shaft.  I also did some M4/M5 and giant ones which were extra-fine M8 x 0.5 threads and some teensy ones with M2 x 0.35 threads.  BA would actually be a better choice because of the thread angle, but I don't own any BA taps/dies.  Using a tapered split collet worked OK at 4mm, but it was getting tricky at smaller diameters.  It was a fun way to idle away some time on a summer afternoon.

Neil G4DBN



On Sat, 30 Jan 2021 at 10:30, John Fell <john.g0api@...> wrote:
"Evanescent filters are so easy to throw together, and drilling too many tapped holes while just playing around .... ".

This from Mr "I don't do mechanical things "   LOL.




Virus-free. www.avg.com


Re: F6BVA 10 GHz transverter PCB group order

Neil Smith G4DBN
 

Invitations to join the IO group to support this group purchase should have gone out just now.  If you have requested a PCB and don't get an invite it is probably because I failed miserably at cut and paste.  Give it half an hour, and if still no invitation arrives, please subscribe manually to:

https://groups.io/g/BVA-transverters-uk

Anyone interested is welcome to join the group, but be aware it will mostly be mightily boring chat about postage, component lists, order progress and technical stuff about this specific project and directly-associated accessories, and the exact meaning of obscure technical French sentences, so don't expect to find a rich seam of astounding insights about the anode structure of the 807 or the latest EFHW. Solder paste choices, fluxes, tips on local oscillator levels, yes for sure.

If you do join and don't have an obvious callsign in your username or profile, you'll be on moderated status until I'm happy you aren't shorting Gamestop or promoting Dogecoin (or EFHWs).

Neil G4DBN


Re: MEMS switches

Murray Niman
 

Menlo used to have more simpler designs, but there was no profit/demand vs alternatives, so they are no longer offered.   RFMEMS is littered with industrial failure , so they have been astute in their history and targets.

As a former RFMEMS engineer, am impressed with their offerings, but do watch the small print.

The Menlo tech is akin a DC contacting relay in miniature , so not rated for live hot switching on most of its specs.

Other RFMEMS can sometimes use so called capacitive contacts for high frequency work (but no DC metal-metal contacts)

73

    Murray G6JYB


Re: MEMS switches

Greg - ZL3IX
 

Two problems with the SKY devices. Firstly I want to use them at 10 GHz, and SKY only does 6 GHz. Secondly I've had problems getting the SKY devices to work. Not sure if they're unusually static sensitive, but my success rate was only about 30% when I assembled my 1.3 GHz transverter.


Re: round attenuator dissasembly?

Robin Szemeti - G1YFG
 

Yep, I suspect a long term occupational exposure is not good ... but for the stuff amateurs are likely to do its not an issue, but a well made cautionary point.   The Be Oxide however is very much worth avoiding, even in small quantities. We had specific disposal routes for damaged BeO containing devices when I was at the beeb.



On Sat, 30 Jan 2021 at 16:12, alwyn.seeds1 <a.seeds@...> wrote:
Dear Robin,

One of the founders of Varian, who did a lot of BeCu turning at Stanford, died prematurely of Be lung damage.

I suppose it’s all a matter of how much exposure and your susceptibility.

Regards,

Alwyn
_____________________________________________________

Alwyn Seeds, Director
SynOptika Ltd.,
114 Beaufort Street,
London,
SW3 6BU,
England.


SynOptika Ltd., Registered in England and Wales: No. 04606737
Registered Office: 114 Beaufort Street, London, SW3 6BU, United Kingdom.
_____________________________________________________


--
Robin Szemeti - G1YFG


Re: EVO Filter construction

Neil Smith G4DBN
 

After Andy mentioned this type of filter some time last year, I had a go at making some. Because of my metalbashing addition and for general bling (and maybe performance), I made the tuning screws from Tellurium Copper, with knurled heads for easy finger-tweaking.  I might still have a few of the tuning screws kicking about if anyone wants some to try.  I cut the threads deliberately oversize to improve the fit, and made slightly thicker than standard brass locknuts, although the pic shows a stainless one.  I also made up some solder-in threaded collars to give a longer thread engagement, but that is more faff than just drilling and tapping the holes.  I used a thread-rolling tap rather than a normal cutting tap for the copper waveguide.  Whether they work any better than brass screws, I didn't have the energy left to investigate, but I had a pile of machine-shop fun, and that's an end in itself. These are M3 x 0.5 with 9mm head and 2.3mm plain shaft.  I also did some M4/M5 and giant ones which were extra-fine M8 x 0.5 threads and some teensy ones with M2 x 0.35 threads.  BA would actually be a better choice because of the thread angle, but I don't own any BA taps/dies.  Using a tapered split collet worked OK at 4mm, but it was getting tricky at smaller diameters.  It was a fun way to idle away some time on a summer afternoon.

Neil G4DBN



On Sat, 30 Jan 2021 at 10:30, John Fell <john.g0api@...> wrote:
"Evanescent filters are so easy to throw together, and drilling too many tapped holes while just playing around .... ".

This from Mr "I don't do mechanical things "   LOL.



Re: round attenuator dissasembly?

alwyn.seeds1
 

Dear Robin,

One of the founders of Varian, who did a lot of BeCu turning at Stanford, died prematurely of Be lung damage.

I suppose it’s all a matter of how much exposure and your susceptibility.

Regards,

Alwyn
_____________________________________________________

Alwyn Seeds, Director
SynOptika Ltd.,
114 Beaufort Street,
London,
SW3 6BU,
England.


SynOptika Ltd., Registered in England and Wales: No. 04606737
Registered Office: 114 Beaufort Street, London, SW3 6BU, United Kingdom.
_____________________________________________________


Re: 24 GHz

Denis Stanton G0OLX
 

To all
I have 2 Watts to Procom dish system for portable. I could put on tripod and look out of the shed door, if required have done 10 GHz rain scatter that way in the past
73’s
Denis G0OLX


On 30 Jan 2021, at 15:46, Steve G4HTZ via groups.io <essexsteve@...> wrote:


Hi Gerard 
My 24ghz system is ready to go on mast soon ...also with a elevation rotator .
I have a sea path into Holland from JO01JN60
Regards 
Steve G4HTZ 


On 30 Jan 2021, at 15:24, gerard.geesink@... wrote:


Gentleman,

24G season will be starting soon. Who of you is permanently QRV? 
Here 2.5W 1.1 m dish ... JO31FX.

73 Gerard PA0BAT

Op 30 jan. 2021 3:19 p.m. schreef "Steve G4HTZ via groups.io" <essexsteve@...>:
Hi Denis 
this may be an option from I0JXX 

https://www.i0jxx.com/gb/116-24-ghz

--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


Re: 24 GHz

Steve G4HTZ
 

Hi Gerard 
My 24ghz system is ready to go on mast soon ...also with a elevation rotator .
I have a sea path into Holland from JO01JN60
Regards 
Steve G4HTZ 


On 30 Jan 2021, at 15:24, gerard.geesink@... wrote:


Gentleman,

24G season will be starting soon. Who of you is permanently QRV? 
Here 2.5W 1.1 m dish ... JO31FX.

73 Gerard PA0BAT

Op 30 jan. 2021 3:19 p.m. schreef "Steve G4HTZ via groups.io" <essexsteve@...>:
Hi Denis 
this may be an option from I0JXX 

https://www.i0jxx.com/gb/116-24-ghz

--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


Re: 24 GHz Feed Horn

Steve G4HTZ
 

I have the 10ghz one ...ordered beginning of January arrived via UPS in 4 days 

On 30 Jan 2021, at 15:12, Denis Stanton G0OLX <Stantondenis@...> wrote:

Steve
Just went to order one but would not take UK address details.
The 10Ghz feed looks good as well
I wonder why the UK dos'nt appear in the countries list.
Will wait to I get to work on Tuesday and give them a ring
Many thanks for info
Denis
G0OLX

--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


Re: 24 GHz Feed Horn

John Lemay
 

Denis

 

I’m using a ‘JXX feed for my PF dish on 3cms, and it works fine, better than the RF HamDesign loop. I think the ‘JXX 10 and 24GHz parts are sub-contracted.

 

If you need anything else, I regularly import his aerials and it’s easy for me to add bits and pieces to an order. I’ve not imported dish feeds, considering the market to be quite small, but I’m happy to be proved wrong – after all, 50 feeds will be needed soon for those 50 F6BVA transverters !

 

John G4ZTR

 

From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Denis Stanton G0OLX
Sent: 30 January 2021 15:27
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 24 GHz Feed Horn

 

I0JXX have just sent me a Login code so that I can now place a order
Lets see how I get on
Thanks everybody Best 73's


Virus-free. www.avg.com


Re: 24 GHz Feed Horn

John Quarmby
 

You could try Aerial Parts of Colchester. John G4ZTR is a UK agent for I0JXX antennas.

73

John G3XDY

On 30/01/2021 15:23, Denis Stanton G0OLX wrote:
Neil
Thanks for the offer on the 24 GHz horn
I0JXX looks good if I can get one!!!! I might also go for the 10GHz feed horn as well
It may be the customs problem after brexit as there is not a UK or GI listing in the countries lists
I will let you all know how I get on
Best 73’s


On 30 Jan 2021, at 15:12, Denis Stanton G0OLX via groups.io <Stantondenis@...> wrote:

Steve
Just went to order one but would not take UK address details.
The 10Ghz feed looks good as well
I wonder why the UK dos'nt appear in the countries list.
Will wait to I get to work on Tuesday and give them a ring
Many thanks for info
Denis
G0OLX

Virus-free. www.avast.com


Re: 24 GHz

John Quarmby
 

Hi Gerard

My 24GHz system is not permanently on the tower during the winter but only takes 30 minutes to install. It will be up there when there is tropo or a good chance of rainscatter.

3W to 48cm PF dish JO02OB.

73

John G3XDY

On 30/01/2021 15:24, gerard.geesink@... wrote:
Gentleman,

24G season will be starting soon. Who of you is permanently QRV? 
Here 2.5W 1.1 m dish ... JO31FX.

73 Gerard PA0BAT

Op 30 jan. 2021 3:19 p.m. schreef "Steve G4HTZ via groups.io" <essexsteve@...>:
Hi Denis 
this may be an option from I0JXX 

https://www.i0jxx.com/gb/116-24-ghz

--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


Virus-free. www.avast.com


Re: 24 GHz Feed Horn

Dominique Dehays
 

Hi all,

Personnaly I would avoid a horn using tuning screws like the 3cm JXX , I can understand mr Joe Ham uses tuning screws on his home made horn , but not on a commercial horn

73
Dom


Re: 24 GHz Feed Horn

Denis Stanton G0OLX
 

I0JXX have just sent me a Login code so that I can now place a order
Lets see how I get on
Thanks everybody Best 73's


24 GHz

Gerard Geesink
 

Gentleman,

24G season will be starting soon. Who of you is permanently QRV? 
Here 2.5W 1.1 m dish ... JO31FX.

73 Gerard PA0BAT

Op 30 jan. 2021 3:19 p.m. schreef "Steve G4HTZ via groups.io" <essexsteve@...>:

Hi Denis 
this may be an option from I0JXX 

https://www.i0jxx.com/gb/116-24-ghz

--
Steve G4HTZ 
JO01JN60
Great Wakering, Essex 
24ghz 1.8w 80cm dish 

also known to be active occasionally on 70cms DATV 


Re: 24 GHz Feed Horn

Denis Stanton G0OLX
 

Neil
Thanks for the offer on the 24 GHz horn
I0JXX looks good if I can get one!!!! I might also go for the 10GHz feed horn as well
It may be the customs problem after brexit as there is not a UK or GI listing in the countries lists
I will let you all know how I get on
Best 73’s


On 30 Jan 2021, at 15:12, Denis Stanton G0OLX via groups.io <Stantondenis@...> wrote:

Steve
Just went to order one but would not take UK address details.
The 10Ghz feed looks good as well
I wonder why the UK dos'nt appear in the countries list.
Will wait to I get to work on Tuesday and give them a ring
Many thanks for info
Denis
G0OLX


Re: 24 GHz Feed Horn

Denis Stanton G0OLX
 

Steve
Just went to order one but would not take UK address details.
The 10Ghz feed looks good as well
I wonder why the UK dos'nt appear in the countries list.
Will wait to I get to work on Tuesday and give them a ring
Many thanks for info
Denis
G0OLX


Re: 24 GHz Feed Horn

Denis Stanton G0OLX
 

Thanks Steve that looks very interesting
Denis G0OLX

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