Date   

Re: Marconi 6960B

Robin Szemeti - G1YFG
 

My router is INT30,  with ER32 collets ... I keep hankering after a Burnerd collet chuck for my Colchester Student ...

On Wed, 4 Nov 2020 at 11:55, Paul G8AQA via groups.io <paulnick=btinternet.com@groups.io> wrote:
My milling machine takes International 30 tooling.  I have managed to collect most tooling I want except a collet chuck which I also want for my lathe. I want collets that will fit both lathe and milling machine.  Some of the ebay stuff has too much runout.  Ideally ER32 would be good.

73
Paul.

On 03/11/2020 20:07, Neil Smith G4DBN wrote:
Sadly, my old Bridgeport clunker only takes native R8 tooling. Easy to fine ISO40 to R8, but the other way round isn't exactly a sensible idea.  If I ever have to rebuild the spindle and quill, I might convert to ISO40.

I just spotted the Dean Smith and Grace 1306 lathe in that auction.  Now I am sad because I don't quite have the floor space. It would mean knocking an internal blockwork wall down. If it goes for less than £1k, I'm going to kick myself for months. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26 <https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26> Fancy putting that through Palletforce?

Neil G4DBN

On 03/11/2020 18:27, Robin Szemeti - G1YFG wrote:
That reminds me Neil,  will your mill take an ISO40 taper?   We sold our Haas VF2 years ago, but I occasionally see lumps of tooling lurking in long forgotten boxes.








--
Robin Szemeti - G1YFG


Re: Marconi 6960B

Paul G8AQA
 

My milling machine takes International 30 tooling.  I have managed to collect most tooling I want except a collet chuck which I also want for my lathe. I want collets that will fit both lathe and milling machine.  Some of the ebay stuff has too much runout.  Ideally ER32 would be good.

73
Paul.

On 03/11/2020 20:07, Neil Smith G4DBN wrote:
Sadly, my old Bridgeport clunker only takes native R8 tooling. Easy to fine ISO40 to R8, but the other way round isn't exactly a sensible idea.  If I ever have to rebuild the spindle and quill, I might convert to ISO40.

I just spotted the Dean Smith and Grace 1306 lathe in that auction.  Now I am sad because I don't quite have the floor space. It would mean knocking an internal blockwork wall down. If it goes for less than £1k, I'm going to kick myself for months. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26 <https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26> Fancy putting that through Palletforce?

Neil G4DBN

On 03/11/2020 18:27, Robin Szemeti - G1YFG wrote:
That reminds me Neil,  will your mill take an ISO40 taper?   We sold our Haas VF2 years ago, but I occasionally see lumps of tooling lurking in long forgotten boxes.








Real DX !

militaryoperator
 

NASA reestablishes contact with 43-year-old Voyager 2 which is 11.6 BILLION miles from Earth after repairs to antenna in Australia left spacecraft flying solo for seven months

  • Voyager 2 has been traveling through space since launching in 1977 
  • The spacecraft is now more than 11.6 billion miles away from Earth
  • NASA cutoff communication with the probe in March to repair a satellite
  • The Deep Space Station 43 antenna in Australia went back online and sent Voyager 2 a signal
  • The craft received the signal and sent a reply that reached NASA 34 hours later

WOW


Coax for dish feed (suggestions please).

Andy GD1MIP
 

I am putting together two dishes for 13 & 9cm. 

My plan is a multiband Vivaldi feed with an SMA connector to an SMA on a transverter mounted on the rear of the dish, currently 3w max power, but may go up to 10w later.

So I need two  roughly 1 to 2m lengths of the  lowest loss coax I can afford. Succoflex 100 has been suggested. 

Are there any better options and suggestions of a source?

Thanks Andy GD1MIP 


Re: Marconi 6960B

Neil Smith G4DBN
 

Sadly, my old Bridgeport clunker only takes native R8 tooling. Easy to fine ISO40 to R8, but the other way round isn't exactly a sensible idea.  If I ever have to rebuild the spindle and quill, I might convert to ISO40.

I just spotted the Dean Smith and Grace 1306 lathe in that auction.  Now I am sad because I don't quite have the floor space. It would mean knocking an internal blockwork wall down. If it goes for less than £1k, I'm going to kick myself for months. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26 <https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-d4187768-3f4a-4c48-b9a7-ac6301154d26> Fancy putting that through Palletforce?

Neil G4DBN

On 03/11/2020 18:27, Robin Szemeti - G1YFG wrote:
That reminds me Neil,  will your mill take an ISO40 taper?   We sold our Haas VF2 years ago, but I occasionally see lumps of tooling lurking in long forgotten boxes.


Re: Marconi 6960B

Clint Sharp <cjaysharp@...>
 


Even a valid calibration and unbroken stickers is no guarantee an instrument hasn't been disposed of because someone subjected it to a kilowatt into a 0dBm port, 'For Indication only' isn't a terrible thing, it means the gear was considered good enough to be kept on even after the cal had expired.

It's a likely to work as anything else and chances are it'd sail through a cal.

On Tue, 3 Nov 2020 at 17:52, Neil Smith G4DBN <neil@...> wrote:
They say P&P for standard small parcels up to 30kg will cost £16 (not
sure if plus VAT).  Details are in the fine print as usual, there is a
"phone us for details after you win the bid" statement.

Larger stuff like a 300 kg cast iron surface plate are send via
Palletforce or similar, so for me that's around £50 for a complete
pallet.  Don't think I'll be bidding on the E8361C PNA though, as the
idea of having that strapped down to a pallet is not attractive.
https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-005c1e58-f66d-4203-ad7d-ac610134f040
<https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-005c1e58-f66d-4203-ad7d-ac610134f040>

The details and conditions are at
https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/terms-and-conditions
<https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/terms-and-conditions>

There is an option for "local delivery", so I guess anyone really keen
could arrange for delivery to the car park up the road from the auction
house and pay their local delivery folk to collect the kit and drop it
in your car boot.

I might bid on a couple of bits of kit just for spares, and it if works
then that's a bonus, but I'm not going to spend big.  The PNA is up to
£450, and when you add buyer's premium, VAT and carriage, that is a lot
of coin for a perhaps-dead boat-anchor. Or it could be the bargain of
the century. The Anritsu MS2802A price is ramping up now I see. The
sticker saying "for indication purposes only" is not encouraging!  I'l
looking for some cases with decent meter movements, so don't really care
if the innards are working, so long as the case is in one piece and the
meter isn't obviously wrecked.

Back to the workshop.....

Neil G4DBN

On 03/11/2020 16:39, Paul G8KFW wrote:
> Hi Neil regarding shipping
>
> Are they going to charge for packing  ?
> and how much will the shipping be  ?
>
> Regards  Paul
>








--
Clint. M0UAW IO83

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


Re: Marconi 6960B

Robin Szemeti - G1YFG
 

That reminds me Neil,  will your mill take an ISO40 taper?   We sold our Haas VF2 years ago, but I occasionally see lumps of tooling lurking in long forgotten boxes.

On Tue, 3 Nov 2020 at 15:51, Neil Smith G4DBN <neil@...> wrote:
Always a risk, buying from generic auctions. I think the PNA, SpecAns
and other high-end kit are going to be "fun" buys, given that you either
have it pieces in a cardboard box via Parcelforce, or strapped to a
pallet in a wagon with pallets of bricks, concrete breakers and other
clean-room qualified items.

I might have a punt on one of those enormously-heavy cast-iron surface
plates, they would have to try hard to damage that.

Neil G4DBN

On 03/11/2020 14:38, Robin Szemeti - G1YFG wrote:
> I have bought Marconi heads from that auction before,  it is "sold as
> seen, no guarantees" ... the head I have came from there, with a fresh
> calibration sticker sealing the end cap on, but I am beginning to
> think it is knackered.







--
Robin Szemeti - G1YFG


Re: Marconi 6960B

Neil Smith G4DBN
 

They say P&P for standard small parcels up to 30kg will cost £16 (not sure if plus VAT).  Details are in the fine print as usual, there is a "phone us for details after you win the bid" statement.

Larger stuff like a 300 kg cast iron surface plate are send via Palletforce or similar, so for me that's around £50 for a complete pallet.  Don't think I'll be bidding on the E8361C PNA though, as the idea of having that strapped down to a pallet is not attractive. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-005c1e58-f66d-4203-ad7d-ac610134f040 <https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-005c1e58-f66d-4203-ad7d-ac610134f040>

The details and conditions are at https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/terms-and-conditions <https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/terms-and-conditions>

There is an option for "local delivery", so I guess anyone really keen could arrange for delivery to the car park up the road from the auction house and pay their local delivery folk to collect the kit and drop it in your car boot.

I might bid on a couple of bits of kit just for spares, and it if works then that's a bonus, but I'm not going to spend big.  The PNA is up to £450, and when you add buyer's premium, VAT and carriage, that is a lot of coin for a perhaps-dead boat-anchor. Or it could be the bargain of the century. The Anritsu MS2802A price is ramping up now I see. The sticker saying "for indication purposes only" is not encouraging!  I'l looking for some cases with decent meter movements, so don't really care if the innards are working, so long as the case is in one piece and the meter isn't obviously wrecked.

Back to the workshop.....

Neil G4DBN

On 03/11/2020 16:39, Paul G8KFW wrote:
Hi Neil regarding shipping

Are they going to charge for packing ?
and how much will the shipping be ?

Regards Paul


Re: Mow Cop WebSDR? Change http://mowcopsdr.ddns.net:8901/

Martin G7CKX
 

Hi All.

Just a quick update on the Mow Cop 10GHz SDR.  The DNS that we used for the SDR was done by a pal of mine, who added the original DNS record to his DynDNS account (where he had many)
Unfortunately he has now moved all of his DNS records away from DynDNS and over to a new provider so I've blagged a ride, the new URL for the SDR is

http://mowcopsdr.ddns.net:8901

Maybe in the future I'll be able to get the old URL back, but for now this is a quick fix :)

73's

Martin G7CKX


Re: Marconi 6960B

Paul G8KFW
 

Hi Neil regarding shipping

Are they going to charge for packing ?
and how much will the shipping be ?

Regards Paul

-----Original Message-----
From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of
Neil Smith G4DBN
Sent: 03 November 2020 15:51
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Marconi 6960B

Always a risk, buying from generic auctions. I think the PNA, SpecAns
and other high-end kit are going to be "fun" buys, given that you either
have it pieces in a cardboard box via Parcelforce, or strapped to a
pallet in a wagon with pallets of bricks, concrete breakers and other
clean-room qualified items.

I might have a punt on one of those enormously-heavy cast-iron surface
plates, they would have to try hard to damage that.

Neil G4DBN

On 03/11/2020 14:38, Robin Szemeti - G1YFG wrote:
I have bought Marconi heads from that auction before,  it is "sold as
seen, no guarantees" ... the head I have came from there, with a fresh
calibration sticker sealing the end cap on, but I am beginning to
think it is knackered.








-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.




--
Paul Bicknell G8KFW   South Coast UK


Re: Marconi 6960B

Neil Smith G4DBN
 

Always a risk, buying from generic auctions. I think the PNA, SpecAns and other high-end kit are going to be "fun" buys, given that you either have it pieces in a cardboard box via Parcelforce, or strapped to a pallet in a wagon with pallets of bricks, concrete breakers and other clean-room qualified items.

I might have a punt on one of those enormously-heavy cast-iron surface plates, they would have to try hard to damage that.

Neil G4DBN

On 03/11/2020 14:38, Robin Szemeti - G1YFG wrote:
I have bought Marconi heads from that auction before,  it is "sold as seen, no guarantees" ... the head I have came from there, with a fresh calibration sticker sealing the end cap on, but I am beginning to think it is knackered.


Re: Marconi 6960B

Clint Sharp <cjaysharp@...>
 

I've had gear from RAMCO, I'd probably agree with you that it's usually faulty, I lucked out and it was only fuses that had failed.

A lot of MOD gear is set for 110V and it gets plugged into 230V by accident.

On Tue, 3 Nov 2020 at 14:43, Robin Szemeti - G1YFG <robin@...> wrote:
Infact, I am coming to the conclusion that all the stuff in the Ramco auctions is equipment returned as unserviceable, and rather than repair it, they dispose of it.  Sometimes you might be lucky and the "unserviceable" means a loose connector or a broken plastic button .. but otherwise, it might be properly foobarred.

There was a bucket of 100+ Marconi sensors in the last one, went for about £1200 as I remember.


On Tue, 3 Nov 2020 at 14:38, Robin Szemeti <robin@...> wrote:
I have bought Marconi heads from that auction before,  it is "sold as seen, no guarantees" ... the head I have came from there, with a fresh calibration sticker sealing the end cap on, but I am beginning to think it is knackered.

On Tue, 3 Nov 2020 at 14:00, Neil Smith G4DBN <neil@...> wrote:
The Ramco auction ending on 10th Nov has a number of 6910 heads for sale if anyone has a compatible meter. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-efba38bd-97ae-4099-b695-ac610134f061
This is an unusual auction in that they will ONLY post things (or send on pallets) so the normal issues around having to travel to collect stuff doesn't apply.

Neil G4DBN


--
Robin Szemeti - G1YFG



--
Clint. M0UAW IO83

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


Re: Marconi 6960B

Robin Szemeti - G1YFG
 

Infact, I am coming to the conclusion that all the stuff in the Ramco auctions is equipment returned as unserviceable, and rather than repair it, they dispose of it.  Sometimes you might be lucky and the "unserviceable" means a loose connector or a broken plastic button .. but otherwise, it might be properly foobarred.

There was a bucket of 100+ Marconi sensors in the last one, went for about £1200 as I remember.


On Tue, 3 Nov 2020 at 14:38, Robin Szemeti <robin@...> wrote:
I have bought Marconi heads from that auction before,  it is "sold as seen, no guarantees" ... the head I have came from there, with a fresh calibration sticker sealing the end cap on, but I am beginning to think it is knackered.

On Tue, 3 Nov 2020 at 14:00, Neil Smith G4DBN <neil@...> wrote:
The Ramco auction ending on 10th Nov has a number of 6910 heads for sale if anyone has a compatible meter. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-efba38bd-97ae-4099-b695-ac610134f061
This is an unusual auction in that they will ONLY post things (or send on pallets) so the normal issues around having to travel to collect stuff doesn't apply.

Neil G4DBN


--
Robin Szemeti - G1YFG


Re: Marconi 6960B

Robin Szemeti - G1YFG
 

I have bought Marconi heads from that auction before,  it is "sold as seen, no guarantees" ... the head I have came from there, with a fresh calibration sticker sealing the end cap on, but I am beginning to think it is knackered.

On Tue, 3 Nov 2020 at 14:00, Neil Smith G4DBN <neil@...> wrote:
The Ramco auction ending on 10th Nov has a number of 6910 heads for sale if anyone has a compatible meter. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-efba38bd-97ae-4099-b695-ac610134f061
This is an unusual auction in that they will ONLY post things (or send on pallets) so the normal issues around having to travel to collect stuff doesn't apply.

Neil G4DBN


--
Robin Szemeti - G1YFG


Re: Marconi 6960B

Neil Smith G4DBN
 

The Ramco auction ending on 10th Nov has a number of 6910 heads for sale if anyone has a compatible meter. https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-efba38bd-97ae-4099-b695-ac610134f061
This is an unusual auction in that they will ONLY post things (or send on pallets) so the normal issues around having to travel to collect stuff doesn't apply.

Neil G4DBN


Re: AVANTEK Amplifier Module

Gordon REASON <gordonj.reason@...>
 

Well done Doug .........

It's a bit sad that there is some filler material ,,,,, thats most likely there to stop vibration of wires or components .

The 2 to 3 mA of current , is most likely a DC Regulator bias current to supply a positive 5 to 8 volt positive bias to the Fets  (?) .........

Tantalums , my pet hate .........

Once , again within my employed days , I had a similar thing but with a harder material , I took it to a chemical man , who put it into a jar , of liquid , which gently broke down the epoxy , and it fell away ...... so , have a word with you local chemist ?

On 03 November 2020 at 12:33 DougF VK4OE <uwaves@...> wrote:

Greetings to all readers, and thanks for the various suggestions received on this subject.

I thought that a little update is in order following some purpose-driven investigations which I have made on this amplifier module today.

Firstly, yes, the top cover was held in place by a continuous seam of aluminium welding around the perimeter.  It was easy with a vertical milling machine to carefully remove enough material (only 1.2 mm) in order to be able to see the horizontal dividing line between two metal components all the way around.  After that, the cover with its complicated fitted extensions down into the "microwave electronics space" (most likely structures which prevent spurious oscillations) could easily be lifted free.

One of the accompanying pictures shows the amount of glass-substrate microwave circuitry with all its wire bonding, which was revealed when the top cover was removed.  On initial inspection, nothing seemed glaringly wrong or out of place there.

Next, the bottom plate with all of its screws removed did "pop free" this time with less effort  than I had been using the other day, revealing that it had been some semi-hard silicone cavity filler material which had been preventing detachment of the plate.  A couple of days under less tension with the screws removed may have facilitated it 'letting go'.

As you'll see from the other attached picture, what the bottom plate had been covering is just the DC input componentry, with two DC feed-through-paths leading from this little 'alcove' to the microwave electronics on the top side.  As already mentioned, the carefully milled hole or space there is filled with some sort of semi-hard silicone filler material which may be able to be removed with care using a sharp blade.

Although I have not yet measured what's going on DC-wise there, it is quite possible that the small tantalum capacitor that's present has gone short circuit taking the series diode with it.  Wouldn't it be very nice if the failure that has occurred is as simple as that?!  But that doesn't explain the residual 2 or 3 mA of current....  If those DC feed components test good, then the fault is likely to be in the impossible-to-work-on microwave electronics, leading to the amplifier being 'written off' with the only benefit from having investigated is to reveal things about these modules which may help others at a later time.

It may be a couple more days before I get back to these investigations, so I thought this update may be of interest to numbers of readers of this thread.  At least my questions about internal construction of AVANTEK amplifier modules of this vintage have been answered.

Cheers and best wishes,

--Doug Friend, VK4OE.

On 02/11/2020 1:12 am, Gordon REASON via groups.io wrote:

You need to know how the inside is milled , but I removed some lids by , using a drill bit with a stop on it , to prevent the drill bit going through and doing damage to internal circuitry .

A connector from a chocholate block connector works well .

Then you can drill the lid , untill you create a hole .

Then very carefully , insert a screwdriver , and apply pressure and a click will indicate that the lid seal has broken .

The weld does'nt go very deep ...........it's a weatherproof seal .

It's best of course , to know the internal milling , then you can drill the lid , with a 2.5 mm hole , tap it with a 3mm tap .

Insert a 3 mm screw , and that will lift the lid off , and that done the lid will probably peel off ....

And as Paul suggested , use a vaccumm to take any swarf away .

I used a scalpel , sometimes to scrape the aluminium  ? ,  flat , for rewelding .. saved hours avoiding milling flat ........still waiting for my medal.


 


 


Re: AVANTEK Amplifier Module

DougF VK4OE
 

Greetings to all readers, and thanks for the various suggestions received on this subject.

I thought that a little update is in order following some purpose-driven investigations which I have made on this amplifier module today.

Firstly, yes, the top cover was held in place by a continuous seam of aluminium welding around the perimeter.  It was easy with a vertical milling machine to carefully remove enough material (only 1.2 mm) in order to be able to see the horizontal dividing line between two metal components all the way around.  After that, the cover with its complicated fitted extensions down into the "microwave electronics space" (most likely structures which prevent spurious oscillations) could easily be lifted free.

One of the accompanying pictures shows the amount of glass-substrate microwave circuitry with all its wire bonding, which was revealed when the top cover was removed.  On initial inspection, nothing seemed glaringly wrong or out of place there.

Next, the bottom plate with all of its screws removed did "pop free" this time with less effort  than I had been using the other day, revealing that it had been some semi-hard silicone cavity filler material which had been preventing detachment of the plate.  A couple of days under less tension with the screws removed may have facilitated it 'letting go'.

As you'll see from the other attached picture, what the bottom plate had been covering is just the DC input componentry, with two DC feed-through-paths leading from this little 'alcove' to the microwave electronics on the top side.  As already mentioned, the carefully milled hole or space there is filled with some sort of semi-hard silicone filler material which may be able to be removed with care using a sharp blade.

Although I have not yet measured what's going on DC-wise there, it is quite possible that the small tantalum capacitor that's present has gone short circuit taking the series diode with it.  Wouldn't it be very nice if the failure that has occurred is as simple as that?!  But that doesn't explain the residual 2 or 3 mA of current....  If those DC feed components test good, then the fault is likely to be in the impossible-to-work-on microwave electronics, leading to the amplifier being 'written off' with the only benefit from having investigated is to reveal things about these modules which may help others at a later time.

It may be a couple more days before I get back to these investigations, so I thought this update may be of interest to numbers of readers of this thread.  At least my questions about internal construction of AVANTEK amplifier modules of this vintage have been answered.

Cheers and best wishes,

--Doug Friend, VK4OE.

On 02/11/2020 1:12 am, Gordon REASON via groups.io wrote:

You need to know how the inside is milled , but I removed some lids by , using a drill bit with a stop on it , to prevent the drill bit going through and doing damage to internal circuitry .

A connector from a chocholate block connector works well .

Then you can drill the lid , untill you create a hole .

Then very carefully , insert a screwdriver , and apply pressure and a click will indicate that the lid seal has broken .

The weld does'nt go very deep ...........it's a weatherproof seal .

It's best of course , to know the internal milling , then you can drill the lid , with a 2.5 mm hole , tap it with a 3mm tap .

Insert a 3 mm screw , and that will lift the lid off , and that done the lid will probably peel off ....

And as Paul suggested , use a vaccumm to take any swarf away .

I used a scalpel , sometimes to scrape the aluminium  ? ,  flat , for rewelding .. saved hours avoiding milling flat ........still waiting for my medal.


Re: Marconi 6960B

Robin Szemeti - G1YFG
 

I have a HP435 with a HP8484 head ...   the HP reference source and the Marconi source measure within a needles width of each other, so I am assuming they are pretty good. 

If you can just try the head on your meter and let me know if you get any sensible readings, I think that will be enough ... I just need to know if it is working really.  And maybe also  the other way round ... try your head on my meter,  I can see the chopper drive and voltages look correct to the head look correct, I suspect the measurement A-D in the Marconi is sub-optimal.

I'm in Bewdley, north of Worcester, but I can shuck them at the UPS driver easily enough.


On Tue, 3 Nov 2020 at 10:39, Paul G8KFW <paul@...> wrote:

Hi Robin

 

Actually I don’t think I have actually measured the signals on the head  probably put them on a scope in my early days  what HP power meter set up do you have ?

Sorry I don’t have your location

 

Regards Paul  07719 208048


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Robin Szemeti - G1YFG
Sent: 03 November 2020 02:05
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Marconi 6960B

 

That would be perfect.   

 

I've measured various signals and voltages, and the head appears to be down in sensitivity somewhat, but if I provide it with a slightly higher cal signal to compensate, and deliver the correct signal level at the various stages, it still fails to cal ... it would be nice to figure out which bits are knick-kancked!

 

At least my HP meter works!

 

On Tue, 3 Nov 2020 at 00:13, Paul G8KFW <paul@...> wrote:

Hi robin

I live in West Sussex on the south coast UK  

I will check out but I should have 2 off Marconi 6960 B providing they are working sorry neither is for sale

As they are part of a proposed Calibration rig

 

But I can check your head and meter out for you and they can be checked agenised a Marconi or a HP head

 

Regards Paul


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Robin Szemeti - G1YFG
Sent: 02 November 2020 23:59
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Marconi 6960B

 

I'm having trouble deciding which is the problem item out of my Marconi 6960B and measuring head ...

 

I bought them in differing places,  the head was supposed to be a good 'un, the meter was supposed to be faulty ... I am unsure if either statement is correct.  I get 0.000 with the source off .. and -0.24 mW with the source on ... negative ... almost all the "dead" heads I have seen in the past have simply failed to respond if blown, not go negative ...

 

Does anyone have a known working 6960B?  Could I send you my measuring head to check?

 

Best regards,

Robin Szemeti

Redpoint Consulting Limited 

E: robin@... 

T: +44 (0) 1299 405028 

M: +44 (0) 7971 883371 

Thank you. 


Robin Szemeti - G1YFG

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


Paul Bicknell G8KFW   South Coast UK


Robin Szemeti - G1YFG

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


--
Robin Szemeti - G1YFG


Re: Marconi 6960B

Paul G8KFW
 

Hi Robin

 

Actually I don’t think I have actually measured the signals on the head  probably put them on a scope in my early days  what HP power meter set up do you have ?

Sorry I don’t have your location

 

Regards Paul  07719 208048


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Robin Szemeti - G1YFG
Sent: 03 November 2020 02:05
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Marconi 6960B

 

That would be perfect.   

 

I've measured various signals and voltages, and the head appears to be down in sensitivity somewhat, but if I provide it with a slightly higher cal signal to compensate, and deliver the correct signal level at the various stages, it still fails to cal ... it would be nice to figure out which bits are knick-kancked!

 

At least my HP meter works!

 

On Tue, 3 Nov 2020 at 00:13, Paul G8KFW <paul@...> wrote:

Hi robin

I live in West Sussex on the south coast UK  

I will check out but I should have 2 off Marconi 6960 B providing they are working sorry neither is for sale

As they are part of a proposed Calibration rig

 

But I can check your head and meter out for you and they can be checked agenised a Marconi or a HP head

 

Regards Paul


From: UKMicrowaves@groups.io [mailto:UKMicrowaves@groups.io] On Behalf Of Robin Szemeti - G1YFG
Sent: 02 November 2020 23:59
To: UKMicrowaves@groups.io
Subject: [UKMicrowaves] Marconi 6960B

 

I'm having trouble deciding which is the problem item out of my Marconi 6960B and measuring head ...

 

I bought them in differing places,  the head was supposed to be a good 'un, the meter was supposed to be faulty ... I am unsure if either statement is correct.  I get 0.000 with the source off .. and -0.24 mW with the source on ... negative ... almost all the "dead" heads I have seen in the past have simply failed to respond if blown, not go negative ...

 

Does anyone have a known working 6960B?  Could I send you my measuring head to check?

 

Best regards,

Robin Szemeti

Redpoint Consulting Limited 

E: robin@... 

T: +44 (0) 1299 405028 

M: +44 (0) 7971 883371 

Thank you. 


Robin Szemeti - G1YFG

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


Paul Bicknell G8KFW   South Coast UK


Robin Szemeti - G1YFG

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.


--
Paul Bicknell G8KFW   South Coast UK


EMF Exposure - RSGB Latest Update

G4LDR
 

Please see the following links to the latest information from the RSGB regarding the second stage of OFCOM consultation on EMF Exposure Limits

https://rsgb.org/main/blog/news/rsgb-notices/2020/11/02/updated-response-to-ofcom-consultation/

The updated topic page here has more detail in a new 2-page pdf rsgb.org.uk/emf

Besides the response by the RSGB individual amateurs can respond directly to OFCOM, the closing date is the 16th November.

73 Neil G4LDR.

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