name & function of this component cover? (RF shield?)

[Adam Funk]

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?


--
Destiny is what you are supposed to do in life. Fate is what kicks
you in the ass to make you do it. --- Henry Miller

 

[Tom Biasi]

On 4/25/2013 9:20 AM, Adam Funk wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?


Sounds like you know what they are.

 

[Rich Webb]

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com>
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

 

[Adam Funk]

On 2013-04-25, Tom Biasi wrote:

On 4/25/2013 9:20 AM, Adam Funk wrote:
I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?


Sounds like you know what they are.

Well, it's nice to get it confirmed.



--
No sport is less organized than Calvinball!

 

[Adam Funk]

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?


--
svn ci -m 'come back make, all is forgiven!' build.xml

 

[Tom Biasi]

On 4/25/2013 3:25 PM, Adam Funk wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?


RF shield, but most are made to meet a particular design.

 

[John Larkin]

On Thu, 25 Apr 2013 20:25:58 +0100, Adam Funk <a24061@ducksburg.com> wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

RF shield can, maybe. That googles pretty well.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[Rich Webb]

On Thu, 25 Apr 2013 20:25:58 +0100, Adam Funk <a24061@ducksburg.com>
wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

Probably "RF shield." We've always done custom, the better to fit the
shield to the space available, but there are vendors that offer
standard parts. For example <http://www.fotofab.com/cmp_rfshields.php>
However, if you also need holes then you'll almost certainly have to
go custom.

 

[Michael Black]

On Thu, 25 Apr 2013, Tom Biasi wrote:

On 4/25/2013 9:20 AM, Adam Funk wrote:
I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?


Sounds like you know what they are.

"The perforated whatchamacallits".

It almost sounds like a trick question, that somehow there should be
something more than "shielding".

Michael

 

[Michael Black]

On Thu, 25 Apr 2013, Adam Funk wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

It'a not an off the shelf piece. A design is conjured up, it's layed out,

and then that defines the size needed, so it's off to the machine shop to
make the shielding. Obviously it's mass produced in commercial equipment,
but since it's to fit the circuit, it's made for that circuit.

If you were doing it at home, you'd get a metal bending break and bend
some thin brass or whatever thin metal you could get cheap. Tin cans
would offer up small pieces of metal that would work. Or someone else
might solder bits of copper circuit board together to make small shielded
compartments, again especially useful since you can make them to the size
you need. If you weren't up to that, you'd buy miniboxes (now often too
big) to build up isolated stages in.

Or dig through the junk pile until you find something that is the right
size. Older (and thus larger) IF transformers were once a source, once
transistors came along. Copper pipe might be used, with end caps. I find
myself often saving those bits of shielding from commercial equipment
because they can make neat boxes for this. Anything that offers up a
small box of about the right size is useful, though less likely to be
found in today's electronic equipment.

Michael

 

[John Larkin]

On Thu, 25 Apr 2013 16:57:40 -0400, Rich Webb <webb.ra@example.net> wrote:

Check out the video: a surface-mount can with removable lid.

http://www.lairdtech.com/Products/EMI-Solutions/EMI-Shielding-and-Gaskets/Board-Level-Shielding/

They claim to have some standard parts.




--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[Phil Allison]

"Adam Funk"

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

** RF shielding is certainly the purpose - but the other way around.

Those ICs inside generate RFI that could upset services like TV or Wi-Fi so
the shielded box is to keep it in.

What are they called?

** The material is typically tin plated steel.

So tin boxes will do.

You see the same in most TV sets, VCRs and FM tuners - housing the tuner
itself.


.... Phil

 

[Phil Hobbs]

On 4/25/2013 11:15 PM, John Larkin wrote:

On Thu, 25 Apr 2013 16:57:40 -0400, Rich Webb <webb.ra@example.net> wrote:



Check out the video: a surface-mount can with removable lid.

http://www.lairdtech.com/Products/EMI-Solutions/EMI-Shielding-and-Gaskets/Board-Level-Shielding/

They claim to have some standard parts.

I have a bunch of those. They're pretty nice, actually.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510 USA
+1 845 480 2058

hobbs at electrooptical dot net
http://electrooptical.net

 

[Adam Funk]

On 2013-04-25, Michael Black wrote:

On Thu, 25 Apr 2013, Tom Biasi wrote:

On 4/25/2013 9:20 AM, Adam Funk wrote:
I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?


Sounds like you know what they are.

"The perforated whatchamacallits".

It almost sounds like a trick question, that somehow there should be
something more than "shielding".

Good one! Thanks, everybody.


--
In the 1970s, people began receiving utility bills for
-ÂŁ999,999,996.32 and it became harder to sustain the
myth of the infallible electronic brain. (Verity Stob)

 

[Adam Funk]

On 2013-04-26, Phil Allison wrote:

"Adam Funk"

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?


** RF shielding is certainly the purpose - but the other way around.

Those ICs inside generate RFI that could upset services like TV or Wi-Fi so
the shielded box is to keep it in.

Interesting, thanks.


--
Slade was the coolest band in England. They were the kind of guys
that would push your car out of a ditch. --- Alice Cooper

 

[Phil Hobbs]

On 04/26/2013 11:01 AM, George Herold wrote:

On Apr 26, 12:07 am, Phil Hobbs
pcdhSpamMeSensel...@electrooptical.net> wrote:
On 4/25/2013 11:15 PM, John Larkin wrote:

On Thu, 25 Apr 2013 16:57:40 -0400, Rich Webb <webb...@example.net> wrote:

Check out the video: a surface-mount can with removable lid.

http://www.lairdtech.com/Products/EMI-Solutions/EMI-Shielding-and-Gas...

They claim to have some standard parts.

I have a bunch of those. They're pretty nice, actually.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510 USA
+1 845 480 2058

hobbs at electrooptical dot nethttp://electrooptical.net

We get some things like that from leader tech.
http://www.leadertechinc.com/
I've just used the 'fencing' without the top... that was enough to
stop capacitive feedback in a high gain amp.
It all seems way over priced to me. I seem to recall ~$25 for a 2"x2"
fencing and top.

I also buy stuff from these guys,
http://www.orbel.com/

A little PCB shield 100 for ~$4 each. It was cheaper to design the
circuit to fit under the shield than making a custom shield.

George H.

The Laird ones are cheaper than that, and really very nice. I like

being able to work on stuff without having to desolder the shield.

Here's Digikey's selection: http://tinyurl.com/cy6u9nu

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[George Herold]

On Apr 26, 12:07 am, Phil Hobbs
<pcdhSpamMeSensel...@electrooptical.net> wrote:

On 4/25/2013 11:15 PM, John Larkin wrote:

On Thu, 25 Apr 2013 16:57:40 -0400, Rich Webb <webb...@example.net> wrote:

Check out the video: a surface-mount can with removable lid.

http://www.lairdtech.com/Products/EMI-Solutions/EMI-Shielding-and-Gas...

They claim to have some standard parts.

I have a bunch of those.  They're pretty nice, actually.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510 USA
+1 845 480 2058

hobbs at electrooptical dot nethttp://electrooptical.net

We get some things like that from leader tech.
http://www.leadertechinc.com/
I've just used the 'fencing' without the top... that was enough to
stop capacitive feedback in a high gain amp.
It all seems way over priced to me. I seem to recall ~$25 for a 2"x2"
fencing and top.

I also buy stuff from these guys,
http://www.orbel.com/

A little PCB shield 100 for ~$4 each. It was cheaper to design the
circuit to fit under the shield than making a custom shield.

George H.

 

[Ian Field]

"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:k36jn8lgcphrl7lfvc58q27jflmug3av4r@4ax.com...

On Thu, 25 Apr 2013 20:25:58 +0100, Adam Funk <a24061@ducksburg.com
wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

RF shield can, maybe. That googles pretty well.

"screening can" has been in common usage for some time.

 

[John Larkin]

On Sat, 27 Apr 2013 19:42:04 +0100, "Ian Field" <gangprobing.alien@ntlworld.com>
wrote:

"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:k36jn8lgcphrl7lfvc58q27jflmug3av4r@4ax.com...
On Thu, 25 Apr 2013 20:25:58 +0100, Adam Funk <a24061@ducksburg.com
wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

RF shield can, maybe. That googles pretty well.


"screening can" has been in common usage for some time.

That sounds sort of British to me. I wish you guys would learn to talk proper
American.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

 

[Ian Field]

"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:bt7on8hdkt6frssvjeluuclep5vsvsh5vn@4ax.com...

On Sat, 27 Apr 2013 19:42:04 +0100, "Ian Field"
gangprobing.alien@ntlworld.com
wrote:



"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in
message
news:k36jn8lgcphrl7lfvc58q27jflmug3av4r@4ax.com...
On Thu, 25 Apr 2013 20:25:58 +0100, Adam Funk <a24061@ducksburg.com
wrote:

On 2013-04-25, Rich Webb wrote:

On Thu, 25 Apr 2013 14:20:30 +0100, Adam Funk <a24061@ducksburg.com
wrote:

I was taking a piece of scrap equipment (old cable modem, I think)
apart just to see what was in it, & noticed two perforated removable
cases around some of the components.

Photos:
http://www.ducksburg.com/diy/20130323-electronic0.jpg
http://www.ducksburg.com/diy/20130323-electronic1.jpg

I suspect the cases are grounded but perforated to allow airflow but
shield the contents from radio interference --- is that right?

What are they called?

Doghouses. That's not their formal name but it is what we call 'em.

Thanks! What would they be called in a catalogue (for example)?

RF shield can, maybe. That googles pretty well.


"screening can" has been in common usage for some time.

That sounds sort of British to me. I wish you guys would learn to talk
proper
American.

If it weren't for British English, you'd all be speaking French.