1023	2007-09-16 17:09:39	Gary Johnson	Mounting Toroids
Message	Date	From	Subject
What are the electrical effects of mounting troidal inductors flat upon a ground plane versus standing upright? I've seen surprisingly little information, and no hard data, on this subject. There is some conjecture floating around. I don't have a full 3D dynamic Maxwellian solver handy to simulate the situation, so maybe I'll go out and do some experiments. Meanwhile, does anyone have anything they'd like to share? -Gary, WB9JPS
1024	2007-09-16 17:18:33	brainerd@wildblue...	Re: Mounting Toroids
On 17 Sep 2007 at 0:07, Gary Johnson wrote: > What are the electrical effects of mounting troidal inductors flat upon a ground plane versus > standing upright? I've seen surprisingly little information, and no hard data, on this subject. > There is some conjecture floating around. I don't have a full 3D dynamic Maxwellian solver > handy to simulate the situation, so maybe I'll go out and do some experiments. Meanwhile, > does anyone have anything they'd like to share? > > -Gary, WB9JPS > I have wondering the same thing. I am designing a circuit for some high power low pass filters using t-98 or t-106 toroids. Almost all designs I see they are not mounted flat. Dave - WB6DHW <http://wb6dhw.com>
1025	2007-09-16 17:24:33	Luiz Amaral	Re: Mounting Toroids
If the ground plane is not magnetic, only a conductor, this will increase the capacitance between the turns and ground. Depending on the real use, it may be bad... Luiz - PY1LL / PY4LC ----- Original Message -----
1026	2007-09-16 17:34:20	wbdmxbaileybobbut...	Re: Mounting Toroids

1027	2007-09-16 23:42:00	Baruch Zilbershat...	Re: Mounting Toroids

1028	2007-09-17 08:03:47	R. Snyder	Re: Mounting Toroids
> we usualy place some non conductive material under > an horizentaly > oriented core in ordr to avid flash over of high > voltage and to avid > shorts. RTV silicone adhesive/sealant is typically used to mount toroids to a PCB. However, only non-corrosive silicone should be used, as I've had to repair a HF rig where the manufacturer used acetic-acid-cure silicone, which corroded away one of the leads. If it smells like vinegar, don't use it! Sorry this doesn't answer the original question, but hopefully it will avoid some future reliability problems. ____________________________________________________________________________________ Need a vacation? Get great deals to amazing places on Yahoo! Travel. http://travel.yahoo.com/
1029	2007-09-17 10:14:34	Michael Clarke	Re: Mounting Toroids
On advcie from QRP homebrew gurus, I have used beeswax to secure torroids upright. Melted with a nearby soldering iron tip, the hot wax flows down to form when cold a rigid foot. 73 Michael Mi5mtc
1032	2007-09-17 13:15:56	R. Snyder	Re: Mounting Toroids

1033	2007-09-17 17:43:09	Allison Parent	Re: Mounting Toroids

1034	2007-09-17 18:54:21	Gary Johnson	Re: Mounting Toroids
Thanks for the mechanical mounting suggestions, but to get this thread back on track, what I was originally looking for was real data on the electrical effects of mounting a toroid flat against a groundplane versus standing up. We all have general ideas: The effects are not large; they are second-order, due to local eddy currents in the plane and the winding-to- plane capacitance. But where's the DATA? Anyone done any measurements? Ever seen a published reference on this? -Gary, WB9JPS
1035	2007-09-18 04:13:57	Kenneth Stringham	Re: Mounting Toroids
Another alternative that might work is to use a hot glue gun to provide a spacer and an adhesive attachment for the coil. Ken - AE1X ____________________________________________________________________________________ Shape Yahoo! in your own image. Join our Network Research Panel today! http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7
1036	2007-09-18 06:34:08	Bill Noyce	Re: Mounting Toroids
Sorry, no data, though I'd love to see it. What I've done is mount small toroids vertically with hot glue, and larger ones horizontally over some kind of spacer -- sometimes I've used perfboard, other times I've mounted the toroids with nylon washers and nylon bolts & nuts. (I got this latter technique from seeing Jim Kortge's work -- for example, http://www.k8iqy.com/qrprigs/sw30+/PIC00010_320.jpg ) -- Bill, AB1AV On 9/17/07, Gary Johnson <gwj@spamcop.net> wrote: > > Thanks for the mechanical mounting suggestions, but to get this thread back on track, what I > was originally looking for was real data on the electrical effects of mounting a toroid flat > against a groundplane versus standing up. We all have general ideas: The effects are not > large; they are second-order, due to local eddy currents in the plane and the winding-to- > plane capacitance. But where's the DATA? Anyone done any measurements? Ever seen a > published reference on this? > > -Gary, WB9JPS
1037	2007-09-18 08:52:50	Allison Parent	Re: Mounting Toroids

1046	2007-09-19 21:07:02	Mike Czuhajewski	Re: Mounting Toroids
The original question from WB9JPS, which still has not been addressed directly: > What are the electrical effects of mounting toroidal inductors flat upon a ground plane versus standing upright? I've seen surprisingly little information, and no hard data, on this subject. Here's the mail I sent him several days ago-- "This topic came up on some other mail reflector quite a few months ago, and as I recall no one had an answer based on actual experimentation. I resolved that I would do some experiments to find out what the difference would be (I have two Q meters, Boonton 260A and HP 4342A). Not surprisingly, it fell through the cracks and I never got around to it. Maybe this time will be different. If nothing is heard from me in a week, bug me about it and I'll get moving on it." As of today I'm preparing some test fixtures and writing up a quick and dirty test plan to try to cover a number of different variables. This time I'm really going to do the experiments. (But like I told Gary, I may need to be reminded after a while to get me moving again!) 73 DE WA8MCQ