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#airspyhfplus #swl #spyserver #raspberrypi - RPi, AirspyHF+ WellBrook Loop install and testing #airspyhfplus #spyserver #swl #raspberrypi

Bazz <barry.whitehead@...>
 

Hi,
So I now have my Raspberry Pi installed with a AirSpyHF+ running across the network (kit in the loft).
It is connected to a internal ALA1530 Wellbrook loop at about 6M above ground in the loft.

It works fine, accessing it from the ground floor PC or laptop, but I am getting massive amounts of noise during the day.

I have some ferrites on order (FT240-43) but is there anything else I can look at as well?

I was listening to 80M last night with good results, though I think I need to move the loop higher still.
(need to wait to get my DIY rotator sorted, and might move it outside (after some weather sealing).

Also, anyone know if it's possible to change the loop on a Wellbrook with a copper loop, larger than before?
I have another Wellbrook loop the LA5030 I want to play with.

Images and stuff to follow.

Roberto Zinelli
 

My magnetic loop is at 40 cm from floor in garden but  away from home wall and home electric noise. 
73 Robert

Inviato da OldPhone

Il giorno 11 lug 2018, alle ore 19:18, Bazz <barry.whitehead@...> ha scritto:

Hi,
So I now have my Raspberry Pi installed with a AirSpyHF+ running across the network (kit in the loft).
It is connected to a internal ALA1530 Wellbrook loop at about 6M above ground in the loft.

It works fine, accessing it from the ground floor PC or laptop, but I am getting massive amounts of noise during the day.

I have some ferrites on order (FT240-43) but is there anything else I can look at as well?

I was listening to 80M last night with good results, though I think I need to move the loop higher still.
(need to wait to get my DIY rotator sorted, and might move it outside (after some weather sealing).

Also, anyone know if it's possible to change the loop on a Wellbrook with a copper loop, larger than before?
I have another Wellbrook loop the LA5030 I want to play with.

Images and stuff to follow.

Bazz <barry.whitehead@...>
 

Wish I could move it away from the house, but that means moving towards someone else's  :(
Hence the loft.
I ideally want to get it on a pole above the house, but that's a long term solution.

chutton12000
 

I don't think the -43 will help much, assuming  you are trying to get rid of HF noise using them as common mode chokes. A -31 core would be much better.

Chuck

Peter Lindquist SM5GXQ
 

Hi,
the loop is somewhat directional. There are Sharp nulls where the antenna has its broadside. This might be used to "null out" a single source of interference.

Well, I don't Think common mode rejection will help on the antenna itself. But you might consider that some of your home appliances are the source of the interference.

rgds
Peter

Nigel
 

Hi Bazz,

The Wellbrook loops are great, but they always benefit from being outdoors.
They don't need to be very high, and the directional properties of the loop aren't noticeable once you reach a couple of MHz.
Amongst other antennas I have a 5030 in the loft, not too bad, and a 1530 just strapped to a fence outside about 20 to 25m from the house and approx 1.8 m above ground, which is much better. I wanted to put the one outside on a rotator but the storms here soon persuaded me that would never be a very good idea:-)
These two are at right angles which tends to make up for the directionality at LF, so the 5030 is useful for this, but at higher frequencies it's no contest and the outdoor 1530 is always better.
There's really no point in swapping the 5030 loop for copper tube, by all means try it, experimentation is always fun, but whilst it matters for a transmitting loop for an active receive only loop it's probably not worth the effort.
Don't worry either that an outside loop will get nearer to another property as you move it away from yours, obviously that could be an issue but with so much RFI internally self generated these days, from switch mode PSUs etc, chances are you'll be much better off with it outside regardless, and you could always mount it at ground level, which Wellbrook has claimed is fine, and just move it about a bit to see what happens:-)

Nigel, GM8PZR


On Wed, Jul 11, 2018 at 10:58 AM, Bazz wrote:
Hi,
So I now have my Raspberry Pi installed with a AirSpyHF+ running across the network (kit in the loft).
It is connected to a internal ALA1530 Wellbrook loop at about 6M above ground in the loft.

It works fine, accessing it from the ground floor PC or laptop, but I am getting massive amounts of noise during the day.

I have some ferrites on order (FT240-43) but is there anything else I can look at as well?

I was listening to 80M last night with good results, though I think I need to move the loop higher still.
(need to wait to get my DIY rotator sorted, and might move it outside (after some weather sealing).

Also, anyone know if it's possible to change the loop on a Wellbrook with a copper loop, larger than before?
I have another Wellbrook loop the LA5030 I want to play with.

D R
 

Bazz - I agree with everything Nigel has said.  Wellbrook loops don't need height to work well (mine are mounted 400mm and 1200mm above ground level and work brilliantly) - just get them as far away from any houses as you can, even if it's only a few metres, and align them to minimise noise pickup from indoor generators like plasma TV sets and switching power supplies.

As regards modifying the 5030 loop, it would be simple to cut off the existing loop about three inches either side of the amplifier box and attach some Pex-Al-Pex heating tube or even just coax cable to the stubs to get a bigger loop and see how it works - my only concern would be that adding too big a loop will overload the amp if you have any strong broadcast stations nearby, and cause intermodulation problems (but then it's just a matter of trimming back the size of the loop until they disappear again).  Nothing ventured, nothing gained!  I'd be very interested to learn how you get on with your experiments.

Regards,
Dave


On Thursday, 12 July 2018, 22:46:28 GMT+1, Nigel via Groups.Io <poldhu1901@...> wrote:


Hi Bazz,

The Wellbrook loops are great, but they always benefit from being outdoors.
They don't need to be very high, and the directional properties of the loop aren't noticeable once you reach a couple of MHz.
Amongst other antennas I have a 5030 in the loft, not too bad, and a 1530 just strapped to a fence outside about 20 to 25m from the house and approx 1.8 m above ground, which is much better. I wanted to put the one outside on a rotator but the storms here soon persuaded me that would never be a very good idea:-)
These two are at right angles which tends to make up for the directionality at LF, so the 5030 is useful for this, but at higher frequencies it's no contest and the outdoor 1530 is always better.
There's really no point in swapping the 5030 loop for copper tube, by all means try it, experimentation is always fun, but whilst it matters for a transmitting loop for an active receive only loop it's probably not worth the effort.
Don't worry either that an outside loop will get nearer to another property as you move it away from yours, obviously that could be an issue but with so much RFI internally self generated these days, from switch mode PSUs etc, chances are you'll be much better off with it outside regardless, and you could always mount it at ground level, which Wellbrook has claimed is fine, and just move it about a bit to see what happens:-)

Nigel, GM8PZR


On Wed, Jul 11, 2018 at 10:58 AM, Bazz wrote:
Hi,
So I now have my Raspberry Pi installed with a AirSpyHF+ running across the network (kit in the loft).
It is connected to a internal ALA1530 Wellbrook loop at about 6M above ground in the loft.

It works fine, accessing it from the ground floor PC or laptop, but I am getting massive amounts of noise during the day.

I have some ferrites on order (FT240-43) but is there anything else I can look at as well?

I was listening to 80M last night with good results, though I think I need to move the loop higher still.
(need to wait to get my DIY rotator sorted, and might move it outside (after some weather sealing).

Also, anyone know if it's possible to change the loop on a Wellbrook with a copper loop, larger than before?
I have another Wellbrook loop the LA5030 I want to play with.

POReilly
 

Hi, great topic,  I just returned to the hobby of SWL,  my interest was sparked by the advancement in SDR.  I had no choice but to use a active loop, very small garden and lot here at my QTH, I have a lot of RFI from a local police radio tower and Hospital just down the street .. and don’t mention the new Samsung washing machine :( 
I have been using my HF+ with a http://active-antenna.eu/amplifier-kit/  I basically experimented with loops of different sizes configurations until I achieved the best setup. I first went with a 1 meter single loop but it was to noisy to much gain to noise. After 4 revisions I now have double .7 meter phased loop system. I can use both loops together or single, depending on the conditions ( the AAA1 has a controller switch to switch between configurations )
Honestly it’s one of the best broadband receive antennas I have had for shortwave with and with  a low cost of $100 you cant go wrong.
It’s also lots of fun building and experimenting. My next antenna will be a passive antenna to take full advantage of the HF+ sensitively on the good nights ..maybe a inverted U beverage made of coax. 
Here’s another link that has lots of info on revive antennas  http://www.qsl.net/k4fk/presentations/WF-receiver-antennas-SFDXAs.pdf  
The  HF+ rocks and I look forward to finding a perfect antenna for it to truly make it shine despite my current location.
best regards and good DX

POReilly
 

..guess I rambled on there. Don’t pull your Wellbrook apart get a AAA1 and use that to experiment with and place it far away from your house/rfi as possible.. mag loops will work well even at 1.5 meters from ground it’s more important to get it away from electrical interference and the attic is a last choice.  Research fat loop and inductance start here http://www.qsl.net/k4fk/presentations/WF-receiver-antennas-SFDXAs.pdf

Bazz <barry.whitehead@...>
 

On Thu, Jul 12, 2018 at 02:46 PM, Nigel wrote:
Nigel
Thanks, looks like I got some more experimenting to do before I decide on continue in the loft.

Bazz <barry.whitehead@...>
 

Dave thanks for the reply, looking at what you and Nigel have said obviously means I need to look at alternatives rather than sticking with loft placement.
Though I'll still experiment.

Bazz <barry.whitehead@...>
 

POReilly, had these bookmarked for ages, but could never find anyone actually using it.

The possibilities with the AAA1 loop controller looks endless, and maybe I need to get one to play.

Thanks

D R
 

Bazz - I forgot to mention that I've also got an AAA-1 amp, and it's extremely good.  I use it with two 1m double loops at right angles (four loops in all), and it gives excellent results from about 20kHz to at least 55MHz.  If you want to go DIY from scratch, it's definitely the one to go for.  Plenty of options for the loops: copper tube (as I used), aluminium strip (as I'm about to try, for something to do), coax, thick wire, etc..  The total cost of the project was well under half that of a new Wellbrook for at least the same level of performance, and the pleasure of building and installing it.  There are also plenty of designs for homemade amps as well if you just want a single loop - look up "Wellgood loop antenna" or "M0AYF loop antenna", for instance.

Regards,
Dave



On Friday, 13 July 2018, 15:41:40 GMT+1, Bazz <barry.whitehead@...> wrote:


POReilly, had these bookmarked for ages, but could never find anyone actually using it.

The possibilities with the AAA1 loop controller looks endless, and maybe I need to get one to play.

Thanks

Bazz <barry.whitehead@...>
 

Dave, thanks I am looking at this as well, trying to decide what is best for my location and also always fun to play around.
I'll keep you guys updated.

Thanks for all the suggestions and assistance.

Bazz <barry.whitehead@...>
 

Just an update (wow I am quick, even though sat at work).

Just bought a AAA-1 amp for play time, I'll see what it is capable of.

D R
 

You certainly won't be disappointed!

Regards,
Dave


On Friday, 13 July 2018, 20:05:33 GMT+1, Bazz <barry.whitehead@...> wrote:


Just an update (wow I am quick, even though sat at work).

Just bought a AAA-1 amp for play time, I'll see what it is capable of.

POReilly
 

Yes love it but I have wondered compared to a Wellbrook how it would fair.

POReilly
 

Somewhat.. I am assuming this is only low down on the dial 2 MHz and lower ?

Bazz <barry.whitehead@...>
 

Just an update.
Received my AAA1 yesterday for me to play with next week (got a whole week off at last).
This coupled with the fact I get to play with the Wellbrook loops as well.

My AAA1 will more than likely be a double loop side-by-side with a 2 inch air gap between them.
Wanted to make a copper loop but don't have the ability (tool wise) for such a task (this was due to my next project a 3D printed rotator and remote tuner for the cap)

Also I will have time to track down some nasty noise in the house somewhere, I think it is the power over Ethernet adaptors I have but they are being removed next week.