Re: QO-100 Tomorrow

Dave Brown

Nick

How big is the dish? 20cm doesn’t sound right looking at the picture. Looks more like 50/60 cm?

Cunning idea, BTW, to chop it in half. Are you still using the original rear mount bracket to hold both halves?

73

Dave ZL3FJ

From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Nick Gregory G0HIK via groups.io
Sent: Thursday, October 01, 2020 20:20
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] QO-100 Tomorrow

Hi Paul,

Thankyou for the message, it's nice to get some feedback to my posts.

I live in a poor V/UHF/uWave location, so most of my operating is portable by necessity and SOTA is a natural fit.
I see that there are seven nice little hills in the Devon & Cornwall that are in the SOTA association :-

https://www.sotamaps.org/region/G/DC

You may fancy a venture out to them some time in the future.

I use two FT817's, with a SG-Labs transvertor for the up link and a 739 (LNB I.F.) to 2mtr convertor for the downlink from a standard LNB that has a TCXO fitted. The 13cms aerial is a POTY (Google that :) ) the dish is a standard 20cm DATV, cut in half so it can be strapped to a rucsac.
It all runs from one of those little glove box batteries that are used to jump start a cars in an emergency.

Hopefully I'm be able to work you in the future.

Nick G0HIK

Re: Low Cost VNA

Robin Szemeti - G1YFG

I'd be interested to hear on the NWT6000 too, I use the 4.4 GHz version of that device quite regularly and I am impressed.

On Thu, 1 Oct 2020 at 09:18, g4cch_1 <g4cch_1@...> wrote:
Has anyone tried a NWT6000?
Howard G4CCH

--
Robin Szemeti - G1YFG

Re: Low Cost VNA

g4cch_1

Has anyone tried a NWT6000?
Howard G4CCH

Re: QO-100 Tomorrow

Clint Sharp

Work permitting I'll try and listen in on the BATC SDR later today, good luck, hope the conditions are kind to you.

On Thu, 1 Oct 2020 at 08:20, Nick Gregory G0HIK via groups.io <nickg0hik=googlemail.com@groups.io> wrote:
Hi Paul,

Thankyou for the message, it's nice to get some feedback to my posts.

I live in a poor V/UHF/uWave location, so most of my operating is portable by necessity and SOTA is a natural fit.
I see that there are seven nice little hills in the Devon & Cornwall that are in the SOTA association :-

https://www.sotamaps.org/region/G/DC

You may fancy a venture out to them some time in the future.

I use two FT817's, with a SG-Labs transvertor for the up link and a 739 (LNB I.F.) to 2mtr convertor for the downlink from a standard LNB that has a TCXO fitted. The 13cms aerial is a POTY (Google that :) ) the dish is a standard 20cm DATV, cut in half so it can be strapped to a rucsac.
It all runs from one of those little glove box batteries that are used to jump start a cars in an emergency.

Hopefully I'm be able to work you in the future.

Nick G0HIK

--
Clint. M0UAW IO83

No trees were harmed in the sending of this mail. However, a large number of electrons were greatly inconvenienced.

Re: QO-100 Tomorrow

Nick Gregory G0HIK

Hi Paul,

Thankyou for the message, it's nice to get some feedback to my posts.

I live in a poor V/UHF/uWave location, so most of my operating is portable by necessity and SOTA is a natural fit.
I see that there are seven nice little hills in the Devon & Cornwall that are in the SOTA association :-

https://www.sotamaps.org/region/G/DC

You may fancy a venture out to them some time in the future.

I use two FT817's, with a SG-Labs transvertor for the up link and a 739 (LNB I.F.) to 2mtr convertor for the downlink from a standard LNB that has a TCXO fitted. The 13cms aerial is a POTY (Google that :) ) the dish is a standard 20cm DATV, cut in half so it can be strapped to a rucsac.
It all runs from one of those little glove box batteries that are used to jump start a cars in an emergency.

Hopefully I'm be able to work you in the future.

Nick G0HIK

Second round of manufacture of the VK3CV 122GHz board

Tim, VK2XAX

Hi all,

Second run interest is now north of 140 units so I've has some quotes returned from the manufacturers.

The price of the horn & feed/coupler remains unchanged.

The cost of the assembled & tested board has increase by $20 USD due to the lower quantity requested, to$148USD each.

The cost of the blank PCBs is now $3.00 an increase of$1 per board.

I intend to close the interest list next Friday 8th of October and open a new Fundrazr to collect funds for manufacture shortly thereafter.

If you want anything, now is the time to put your hand up, or if you know someone who is looking to get on 122GHz, please let them know ASAP and get them to to contact me to get on the 122GHz second run interest list.

regards

Tim

--
VK2XAX : QF56if : ITU59 : CQ30 : BMARC : WIA

Re: Earthing stacks

Tim, VK2XAX

You might like to check with your local electricity contractor supply shop for earth stakes.

Here in Australia you can buy copper coated steel stakes of various lengths specifically made for this application.

cheers

Tim

On 1/10/20 7:17 am, g4zod@... via groups.io wrote:

My thanks to all the group members who have recently given me good advice on my earth stack problems.

A friend of mine has a heavy duty hammer drill that is unstoppable. I will turn up on my lathe a suitable pointed rod and hopefully this will allow me to punch a hole to a suitable depth.

VK2XAX : QF56if : ITU59 : CQ30 : BMARC : WIA

Re: Low Cost VNA

Gordon REASON

They all use a resistive bridge , so a good wideband response ...............

On 30 September 2020 at 23:38 "Tim, VK2XAX" <VK2XAX@...> wrote:

Hi Mark,

Thanks for your analysis, While I have instruments to do TDR & RL from
10kHz to 6GHz I'm primarily interested in its other functions. Its good
to know that its at least reasonable and not telling pork pies! But
then, that also assumes the operator knows what he's doing too :)

cheers

Tim

On 30/9/20 6:44 pm, Mark GM4ISM via groups.io wrote:
Hi all

I have not done direct comparison tests ( I rarely get my eldery 8754A
VNA out) but a few publications have indicated that the results are

I do however us VNAs extensively and know  their limitation and
pitfalls in their use.

The Nano VNAs stack up moderately well overall and on most
[snip]

--
VK2XAX : QF56if : ITU59 : CQ30 : BMARC : WIA

Re: Low Cost VNA

Tim, VK2XAX

Hi Mark,

Thanks for your analysis, While I have instruments to do TDR & RL from 10kHz to 6GHz I'm primarily interested in its other functions. Its good to know that its at least reasonable and not telling pork pies! But then, that also assumes the operator knows what he's doing too :)

cheers

Tim

On 30/9/20 6:44 pm, Mark GM4ISM via groups.io wrote:
Hi all

I have not done direct comparison tests ( I rarely get my eldery 8754A VNA out) but a few publications have indicated that the results are broadly similar.

I do however us VNAs extensively and know  their limitation and pitfalls in their use.

The Nano VNAs stack up moderately well overall and on most circumstances are  more than adequate
[snip]

--
VK2XAX : QF56if : ITU59 : CQ30 : BMARC : WIA

Earthing stacks

g4zod@btinternet.com

My thanks to all the group members who have recently given me good advice on my earth stack problems.

A friend of mine has a heavy duty hammer drill that is unstoppable. I will turn up on my lathe a suitable pointed rod and hopefully this will allow me to punch a hole to a suitable depth.

Once again the forum has proved a source of useful advice and information.

G4ZOD

Re: BLF7G22L-130N amp, shim or Milling?

Robin Szemeti - G1YFG

I asked the other guy for £15 to cover post and materials, mail me off list if that is acceptable.

On Wed, 30 Sep 2020 at 21:18, malcolm johnson <g0uhy@...> wrote:
Hi Robin,

I also have need of a spreader if you are making more?

73

Malcolm G0UHY

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of Robin Szemeti - G1YFG <robin@...>
Sent: 30 September 2020 19:59
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] BLF7G22L-130N amp, shim or Milling?

The spreader plate I made has gone to its new owner ... one more person has contacted me so I will make another on the CNC,  but I can do more if needed.  I've not actually located the piece of stock I purchased originally for this, but I would guess it was big enough to cut at least more ...

On Wed, 30 Sep 2020 at 20:54, Paul Randall G3NJV <paulfrandall@...> wrote:
I also bought this PA board, not delivered yet. Without machinery, my thinking was limited to using a hand cut 0.7mm copper sheet as a shim. Has anyone used shim like this before? Any problems I should think about?
Thanks Paul

--
Robin Szemeti - G1YFG

--
Robin Szemeti - G1YFG

Re: 70w 23cm amp build, question.

Neil Smith G4DBN

The ninety-odd  spreaders I made were tapped M3. I assumed the idea was to clamp the PCB to the spreader using an M3 screw in the tapped hole for soldering, then discard the M3 and use the M3 tapped hole as an M2.5 clearance (just) hole to fix the whole thing to a heatsink.

Neil G4DBN

On 30/09/2020 21:02, militaryoperator via groups.io wrote:
No, the instructions are the other way,  drill tap 3mm then fix with 2.5mm.

i think the copper tapped to 2.5 was to secure the spreader while the fet is soldered,
Then the holes opened to 3mm to take bolts to compression fit the board and copper spreader to the heatsink, it would not be possible to get the spreader compressed to the heatsink with threads in the copper,
de alec
On Wednesday, 30 September 2020, 18:29:49 BST, militaryoperator via groups.io <military1944@...> wrote:

A bit unclear.

Notes on fitting the heat spreader to the G4BAO/G7NTG 70 watt PA
It says:

The centre holes in the PCB should be opened out to 3mm and secured to the heat spreader with a smear of solder paste in between them with two short M3 stainless steel screws

then says:

The screws are then removed and then the pcb can be fixed to the heatdink with 2 x m2.5mm screws.

If I have tapped two 3mm holes how can 2.5mm bolts fit?

Ben
--
Neil
http://g4dbn.uk

Re: BLF7G22L-130N amp, shim or Milling?

malcolm johnson

Hi Robin,

I also have need of a spreader if you are making more?

73

Malcolm G0UHY

From: UKMicrowaves@groups.io <UKMicrowaves@groups.io> on behalf of Robin Szemeti - G1YFG <robin@...>
Sent: 30 September 2020 19:59
To: UKMicrowaves@groups.io <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] BLF7G22L-130N amp, shim or Milling?

The spreader plate I made has gone to its new owner ... one more person has contacted me so I will make another on the CNC,  but I can do more if needed.  I've not actually located the piece of stock I purchased originally for this, but I would guess it was big enough to cut at least more ...

On Wed, 30 Sep 2020 at 20:54, Paul Randall G3NJV <paulfrandall@...> wrote:
I also bought this PA board, not delivered yet. Without machinery, my thinking was limited to using a hand cut 0.7mm copper sheet as a shim. Has anyone used shim like this before? Any problems I should think about?
Thanks Paul

--
Robin Szemeti - G1YFG

Re: 70w 23cm amp build, question.

militaryoperator

No, the instructions are the other way,  drill tap 3mm then fix with 2.5mm.

i think the copper tapped to 2.5 was to secure the spreader while the fet is soldered,
Then the holes opened to 3mm to take bolts to compression fit the board and copper spreader to the heatsink, it would not be possible to get the spreader compressed to the heatsink with threads in the copper,
de alec

On Wednesday, 30 September 2020, 18:29:49 BST, militaryoperator via groups.io <military1944@...> wrote:

A bit unclear.

Notes on fitting the heat spreader to the G4BAO/G7NTG 70 watt PA
It says:

The centre holes in the PCB should be opened out to 3mm and secured to the heat spreader with a smear of solder paste in between them with two short M3 stainless steel screws

then says:

The screws are then removed and then the pcb can be fixed to the heatdink with 2 x m2.5mm screws.

If I have tapped two 3mm holes how can 2.5mm bolts fit?

Ben

Re: BLF7G22L-130N amp, shim or Milling?

Robin Szemeti - G1YFG

The spreader plate I made has gone to its new owner ... one more person has contacted me so I will make another on the CNC,  but I can do more if needed.  I've not actually located the piece of stock I purchased originally for this, but I would guess it was big enough to cut at least more ...

On Wed, 30 Sep 2020 at 20:54, Paul Randall G3NJV <paulfrandall@...> wrote:
I also bought this PA board, not delivered yet. Without machinery, my thinking was limited to using a hand cut 0.7mm copper sheet as a shim. Has anyone used shim like this before? Any problems I should think about?
Thanks Paul

--
Robin Szemeti - G1YFG

Re: 70w 23cm amp build, question.

a a

i think the copper tapped to 2.5 was to secure the spreader while the fet is soldered,
Then the holes opened to 3mm to take bolts to compression fit the board and copper spreader to the heatsink, it would not be possible to get the spreader compressed to the heatsink with threads in the copper,
de alec

On Wednesday, 30 September 2020, 18:29:49 BST, militaryoperator via groups.io <military1944@...> wrote:

A bit unclear.

Notes on fitting the heat spreader to the G4BAO/G7NTG 70 watt PA
It says:

The centre holes in the PCB should be opened out to 3mm and secured to the heat spreader with a smear of solder paste in between them with two short M3 stainless steel screws

then says:

The screws are then removed and then the pcb can be fixed to the heatdink with 2 x m2.5mm screws.

If I have tapped two 3mm holes how can 2.5mm bolts fit?

Ben

Re: BLF7G22L-130N amp, shim or Milling?

Paul Randall G3NJV

I also bought this PA board, not delivered yet. Without machinery, my thinking was limited to using a hand cut 0.7mm copper sheet as a shim. Has anyone used shim like this before? Any problems I should think about?
Thanks Paul

Re: Antenna stacking - was Low Cost VNA

KENT BRITAIN

I have had four 17 element KLM's for 144 MHz EME and the suggested stacking distances
are very close to what I have used for 30 years, but that 157.9 M (sq) does not make sense!
Kent WA5VJB

On Wednesday, September 30, 2020, 2:08:36 PM CDT, Graham G3TCT <g3tct@...> wrote:

Just looked at this site. The discussion about stacking of yagis uses a formula for antenna aperture with Pi in the numerator, but should be in denominator, so his answer is too high by factor ~10.  Makes his argument rather less persuasive.

Graham
Gπλ24

Owen Duffy has written about it on a number of occasions. He never sits on the fence.

https://owenduffy.net/blog/

Antenna stacking - was Low Cost VNA

Graham G3TCT

Just looked at this site. The discussion about stacking of yagis uses a formula for antenna aperture with Pi in the numerator, but should be in denominator, so his answer is too high by factor ~10.  Makes his argument rather less persuasive.

Graham
Gπλ24

Owen Duffy has written about it on a number of occasions. He never sits on the fence.

https://owenduffy.net/blog/

Re: QO-100 Tomorrow

Paul Randall G3NJV

Nick

Great stuff, reading your exploits is very inspirational, getting out and about must be wonderful for your physical health and those remote places good for the soul.

I haven’t finished my QO100 station yet but will try listen for you, probably on the SDR at Goonhilly (my old sweat shop).

I’d appreciate a quick overview of your portable station when you have the time – how you pack it all in and power it..

Last spring I ordered a patio dish mount and received a 70cm dish instead!

After a quick phone call the dish mount duly arrived but the return pickup for the dish never happened.

So I’ve a brand new dish just sitting here looking for a life haha.

As an aside, what counts as a summit? No high ground around here except some granite lumps in West Penwith, Camborne-Redruth and then Bodmin and its moor.

I’m a (very good) beach caster throw from IN79, the most southerly bit of UK. 2 mins walk.

I also have a boat, has anyone done QO100 maritime mobile before?

Have fun tomorrow.

Best regards, Paul

Sent from Mail for Windows 10

From: Nick Gregory G0HIK via groups.io
Sent: 30 September 2020 18:56
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] QO-100 Tomorrow

Hi Hope to be out tomorrow (1/10/20)  on a fell that I've never visited before.

I dont know if there will much shelter from the wind, but I'm going to give it a try.

It's quite a drive away but best estimate around 11:45 local time, 2400.200 +/-

I look forward to working my two stalwart contacts and anyone else if you can spare a couple of minutes.

Many thanks

Nick G0HIK