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 qrm tale and antenna advice 
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Post qrm tale and antenna advice
the tale begins back in late 2016, I suddenly had s9 of noise on 40m and 20m
my antennas at this time were in my back garden, 33feet long by 20 feet wide, I had an ocf dipole and a mini beam at the time.
after extensive investigation it was found to vdsl noise from the phone pole at the end of my garden, with no less than 27 drop wires running from it ! this was confirmed by a visit from the Ofcom field guy, his advice was to move house .
in 2017 after a bad accident at work , I found myself housebound for a couple of months.
I began to think how I could get around the noise from the phone lines,the only idea I could come up with was to mount antenna in the front garden, all 15 foot square of it, so had to go vertical of course. I mounted a 6m roach pole with wire up the inside and an unun at the bottom fed against earth via a couple of 4 foot earth rods. it works on 20, it tunes on 40 but I think its no more than a dummy load on this band, it does however cut the noise back to a more acceptable level as no phone poles near the front of the house.
I tried using a 10m pole with same set up, however it then is near to the ridge height and therefore begins to pick up the noise again from the pole at the back, can you see my problem gents.
I have been looking at the sandpiper mv range of verticals, as they are short and would give me access to more bands, anyone have any experience of this range of antenna, or indeed any other sugestions, any advice would be great.
many thanks gents
Tom- M0VHC

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Sun Jan 17, 2021 8:38 pm
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 qrm tale and antenna advice 
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M0VHC wrote:
the tale begins back in late 2016, I suddenly had s9 of noise on 40m and 20m
my antennas at this time were in my back garden, 33feet long by 20 feet wide, I had an ocf dipole and a mini beam at the time.
after extensive investigation it was found to vdsl noise from the phone pole at the end of my garden, with no less than 27 drop wires running from it ! this was confirmed by a visit from the Ofcom field guy, his advice was to move house .
in 2017 after a bad accident at work , I found myself housebound for a couple of months.
I began to think how I could get around the noise from the phone lines,the only idea I could come up with was to mount antenna in the front garden, all 15 foot square of it, so had to go vertical of course. I mounted a 6m roach pole with wire up the inside and an unun at the bottom fed against earth via a couple of 4 foot earth rods. it works on 20, it tunes on 40 but I think its no more than a dummy load on this band, it does however cut the noise back to a more acceptable level as no phone poles near the front of the house.
I tried using a 10m pole with same set up, however it then is near to the ridge height and therefore begins to pick up the noise again from the pole at the back, can you see my problem gents.
I have been looking at the sandpiper mv range of verticals, as they are short and would give me access to more bands, anyone have any experience of this range of antenna, or indeed any other sugestions, any advice would be great.
many thanks gents
Tom- M0VHC



I tried a sandpiper MV10, and it was next to useless, and extremely poorly made.

In 2006 I tried a CP6 (bought it new), works very poorly, and poor construction. Trap failed after a year, and I am not in a position exposed to wind. Not hard to rebuild, but takes time to do it in a way that lasts. Been in the garage since 2008, except for a short while to compare it.

I've tried the verticals with a matching unit at the bottom (often with 2000 or 80 somewhere in the name) but they work less well than the vertical you have tried on a fishing pole.

I find it a bit strange that you are getting the noise when you approach ridge height, seems to be suggesting the house is stopping the interference from reaching your antenna.
If that were to be the case, it (and the houses across the road if there are any) would also be stopping the wanted signals.

Are there no regulations preventing you putting a mast in the front garden? Genuine question, I have not seen many like that.

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Mon Jan 18, 2021 6:27 am
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 qrm tale and antenna advice 
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I wasn't impressed with the multi band vertical I had from them model MV6 I think, it was a long time ago though, put me off the company if i'm honest so I couldn't comment on their recent stuff.

Have you considered a magnetic loop instead, less noise, 1m diameter circle...but they are a bit of a faff to move around the bands as they are so narrowband, you all be forever tweaking it.
Can you could use a separate low noise loop rx antenna? I have a £30 ML30+ loop (see Ebay) and it blows away my £300 Hustler trap vertical on receive.


Mon Jan 18, 2021 9:46 am
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 qrm tale and antenna advice 
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G7 KJF wrote:
I wasn't impressed with the multi band vertical I had from them model MV6 I think, it was a long time ago though, put me off the company if i'm honest so I couldn't comment on their recent stuff.

Have you considered a magnetic loop instead, less noise, 1m diameter circle...but they are a bit of a faff to move around the bands as they are so narrowband, you all be forever tweaking it.
Can you could use a separate low noise loop rx antenna? I have a £30 ML30+ loop (see Ebay) and it blows away my £300 Hustler trap vertical on receive.



You need to search for MLA-30 on ebay

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Mon Jan 18, 2021 10:07 am
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 qrm tale and antenna advice 
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thanks for reply lads,i did have an mfj magloop some years ago and was impressed with receive on it,as you say very narrow so constant re- tune required,will have a look at the other loop mentioned,thanks

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Mon Jan 18, 2021 11:06 am
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 qrm tale and antenna advice 
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also been looking online today at rigexpert double 8 magloop, looks very interesting and able to take more transmit power than the mfj models.
cant find a lot of info about then online but they look like they may fit the bill
anyone on here had any experience of this antenna ?

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Mon Jan 18, 2021 4:05 pm
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 qrm tale and antenna advice 
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Sangoma wrote:
G7 KJF wrote:
I wasn't impressed with the multi band vertical I had from them model MV6 I think, it was a long time ago though, put me off the company if i'm honest so I couldn't comment on their recent stuff.

Have you considered a magnetic loop instead, less noise, 1m diameter circle...but they are a bit of a faff to move around the bands as they are so narrowband, you all be forever tweaking it.
Can you could use a separate low noise loop rx antenna? I have a £30 ML30+ loop (see Ebay) and it blows away my £300 Hustler trap vertical on receive.



You need to search for MLA-30 on ebay


I've just tried one of these, and the signals and noise is down from my inverted L, but if I bring the signals up, the noise obviously comes up as well, and there is no difference in signal to noise ratio.

It is only 6' off the ground, so I will try it some day a bit higher and with a rotator.


However, it is very useful as a general coverage antenna, so I have ordered parts to make a micro rotator, and will mount it with some fibre glass rods to hold it more steady (the thin wire really waves about in the wind) or even make a slightly bigger loop out of fibreglass with a wire attached, probably a 1/16" aluminium wire.

It also goes well with the SDR Play :)

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Wed Jan 27, 2021 2:53 pm
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 qrm tale and antenna advice 
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Post Re: qrm tale and antenna advice
RAEAD THE CROSSCOUNTRYWIRELESS INFO ON LOOPS, IT IS VERY GOOD AND BRITISH.


Thu Jan 28, 2021 4:41 pm
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 qrm tale and antenna advice 
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I've been very happy with it as i like a listen around the SW bands, the problem with the amateur bands is they are full of radio amateurs. :D

A 1m loop of copper pipe works very very well on the MLA30+ too. i've got mine mounted on an old dead collinear with the wire removed to hold it up and mounted on a mast.

Well it used to be amazing until i forgot and shoved 50 watts up it, oops.


Thu Jan 28, 2021 5:17 pm
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