Shutting the RPi down - RF leakage
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- Posts: 1215
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Shutting the RPi down - RF leakage
Yesterday my talkback on 144.750 was disrupted by interference from the Raspberry Pi, admittedly running inside a plastic box. I have not previously noticed this issue - possibly as incoming signals were loud enough....
Electrolube used to supply (Farnell showing as not available but others still have it at around £30 a tin) a nickel spray (not cheap, even back in a1986 when I sprayed the insides of 5 BBC-B computer cases) so I'm wondering if there are alternatives.
This seems suitable, https://uk.farnell.com/ambersil/6190011 ... dp/1676599 but before I commit, has anyone tried it for RF screening purposes? Its half the price of the electrolube nickel stuff....
Gareth
Electrolube used to supply (Farnell showing as not available but others still have it at around £30 a tin) a nickel spray (not cheap, even back in a1986 when I sprayed the insides of 5 BBC-B computer cases) so I'm wondering if there are alternatives.
This seems suitable, https://uk.farnell.com/ambersil/6190011 ... dp/1676599 but before I commit, has anyone tried it for RF screening purposes? Its half the price of the electrolube nickel stuff....
Gareth
Re: Shutting the RPi down - RF leakage
I use a RS 220 6233 to prevent this happening.
73
Nick
73
Nick
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- Posts: 1215
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Re: Shutting the RPi down - RF leakage
Thanks Nick, not an option for my (finished build, its got too much hooked up to it and case space is minimal. From memory I had to shorten the supplied screen stand-offs to get it onto the screen back and put the lid on....
Thanks anyway...
Gareth
Thanks anyway...
Gareth
Re: Shutting the RPi down - RF leakage
I have a portadown in a plastic case and that knocks out my qrp labs GPS rx which uses an internal antenna.
I remember rhe bbcb days tim foil used then.
These days I would try copper tape which you can buy in reels.
It is self adhesive and very effective.
I use it to patch up exit entry holes when using an emc chamber
N
I remember rhe bbcb days tim foil used then.
These days I would try copper tape which you can buy in reels.
It is self adhesive and very effective.
I use it to patch up exit entry holes when using an emc chamber
N
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- Posts: 1215
- Joined: Wed Jan 06, 2016 9:46 am
Re: Shutting the RPi down - RF leakage
Worth a try at least on the bits I can get at - new build underway in a rectangular box, that will be easier.....
Just realised that I have the same QRP-Labs clock with occasional 'outages'....my shack PD4 is on the bench RIGHT NEXT TO IT......but not always on...mystery solved. It must radiate like, well, something that radiates...
Gareth
Just realised that I have the same QRP-Labs clock with occasional 'outages'....my shack PD4 is on the bench RIGHT NEXT TO IT......but not always on...mystery solved. It must radiate like, well, something that radiates...
Gareth
Re: Shutting the RPi down - RF leakage
well the tape works so hope you can get some in.
My clock is inside and not too close to a window.
When I first noticed it I saw it was a cloudy damp day so moved it closer to the window..
It did lock up.
I think it must depend upon the field strength which varies with climate.
Not bothered to check it on my analyser but might look one day
73 and good luck
Nick
My clock is inside and not too close to a window.
When I first noticed it I saw it was a cloudy damp day so moved it closer to the window..
It did lock up.
I think it must depend upon the field strength which varies with climate.
Not bothered to check it on my analyser but might look one day
73 and good luck
Nick
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- Posts: 1215
- Joined: Wed Jan 06, 2016 9:46 am
Re: Shutting the RPi down - RF leakage
Found this too, https://www.screwfix.com/p/no-nonsense- ... 00ml/40801 having looked inside box its got so many mounting bumps its going to be a mess to try and copper-tape it.
Research continuing....the old Electrlube stuff has been replaced by a -P version that doesn't stick as well, according to the forums. And its expensive!
Gareth
Research continuing....the old Electrlube stuff has been replaced by a -P version that doesn't stick as well, according to the forums. And its expensive!
Gareth
Re: Shutting the RPi down - RF leakage
You would also need to make sure surface is keyed very well before application which it sounds likely to be tricky......
Good luck
N
Good luck
N
Re: Shutting the RPi down - RF leakage
Farnell stock the MG Chemicals ‘SuperShield’ Nickel spray. Stock no 2811914
As you say, it is expensive but does a good job. The resistivity of the film created is very low, only a few ohms per square. I used it to spray the plastic box of one of my Langstones, and it helped a lot. It sticks very well. I also used it when making my copper plated reflectors for 122GHz.
Colin G4EML.
As you say, it is expensive but does a good job. The resistivity of the film created is very low, only a few ohms per square. I used it to spray the plastic box of one of my Langstones, and it helped a lot. It sticks very well. I also used it when making my copper plated reflectors for 122GHz.
Colin G4EML.
Re: Shutting the RPi down - RF leakage
Similar thread here:
viewtopic.php?f=15&t=7480&p=28078#p28078
I used one of the metal case/heatsink and coated the rear of the plastic screen box in aluminium tape which does reduce radiation but does not completely remove it and so ended up putting the Pi in a diecast box with a metal grille lid to let the heat out.
Doesn't completely cure it as some radiation is from the front of the screen and some menu pages which have a lot of bright content are worse than others, but it is now at acceptable levels.
Noel
viewtopic.php?f=15&t=7480&p=28078#p28078
I used one of the metal case/heatsink and coated the rear of the plastic screen box in aluminium tape which does reduce radiation but does not completely remove it and so ended up putting the Pi in a diecast box with a metal grille lid to let the heat out.
Doesn't completely cure it as some radiation is from the front of the screen and some menu pages which have a lot of bright content are worse than others, but it is now at acceptable levels.
Noel