Shielding WiFi interference

[Comity]

Hi, I was thinking about the possibility of using aluminum foil to shield my Stereomour from WiFi interference. Maybe lining the sides and bottomi of the Stereomour box with aluminum foil, creating an encasement of sorts? I can’t move my router and was hoping to use a quick fix like this. I appreciate any advice/ feedback on this approach. Thank you.

[Paul Joppa]

It would be preferable to use perforated plate material on the bottom to permit cooling airflow and prevent component failures. And of course be aware that this may or may not do the job - radiation can be picked up by the input or output wires, or the tubes  themselves.

[Comity]

Thanks Paul. I appreciate your input very much. I was also thinking the ventilation to the bottom components may not be sufficient with a sealed foil encasement and your comments confirmed that.  I will use your suggestion and use a perforated lining on the bottom and see what that gets me. Hopefully that will do it. If not, maybe some shielded interconnects.

[Deluk]

I'd want to be certain that I was actually having WiFi interference before trying things. The double diode mod to the power input connections can work miracles if you haven't done that.

[VoltSecond]

1/4 inch galvanized hardware cloth also makes a decent shield.  The wires and parts that are being shielded have to be a short distance from the mesh.  What is short? That depends. Start with being 3 square of mesh away, but 5 is better.  1 square of mesh away doesn't do much at all.

If not twisting the wires together to shape it and bond the edges together, it can be soldered. BUT, it needs a special flux to solder to the galvanized steel. Soldering zinc can release nasty fumes so gear up with a real face mask, not a left over N95.  I'd try twisting the wires first.

"https://www.lowes.com/pd/Blue-Hawk-Actual-10-ft-x-2-ft-Galvanized-Steel-Welded-Wire-Garden-Hardware-Cloth-Rolled-Fencing/1000367329"

RF noise can also be fought with Ferrite beads and small ceramic capacitors.   Small ceramic capacitors (0.01uF) added to a single point ground generate a "hybrid ground" where low frequencies behave as a single point ground for noise control (normally the best method) and high frequencies are grounded at multiple places (normally the best method.)  Long leads on the capacitors make them useless at Radio Frequencies (RF).

[Paul Birkeland]

Small ceramic capacitors (0.01uF) added to a single point ground generate a "hybrid ground" where low frequencies behave as a single point ground for noise control (normally the best method) and high frequencies are grounded at multiple places (normally the best method.)  Long leads on the capacitors make them useless at Radio Frequencies (RF).

We have been adding this to many of our kits as we redo them (at PJ's direction).

It's good to see you back, what have you been up to?

[VoltSecond]

Hi Paul !  ( Hi to PJ too when he gets around to this message. )

The reason I dropped off the map years ago because I started a family and at the same time I was working decades of back to back large programs at work.  This is all changing very soon.  MilliVolt is leaving for college (computer science) and I'm going to retire from paid engineering work.   What am I going to do? Besides travel and honey-do's, my plans are to update my website and bring it back to life, and then build tube and solid state amps just for the heck of it (Un-paid Engineering work AKA Hobby Work.)

In support of bringing my website back to life, for a high school project MilliVolt wrote a Java Script page to calculate optimum bias points for paralleled triodes.  And yes, that page will be in the new version of my webpages. I still need to pick a site name. Unfortunately, calling my website OUCH.COM will attract the wrong group of people.

Going forward with tube designs, I've got a crazy idea on how to make choke input supplies regulate down to no-load as one of the things that is on the list of things to build. Also, I have a newer CCS topology I'd like to discuss with you and PJ after things settle down a bit in September.

Note: I think it is funny that the forum's Spell Checker doesn't recognize "Triodes."  ;-}