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Source for Type 31 Toroids

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Ken Alexander-2

Source for Type 31 Toroids

I have some interference problems with my receivers and have been
reading Jim K9YCs excellent article on the subject. It sounds like type
31 ferrite toroids will be the answer to some of my problems and I'm
interestedin buying some.

I had always considered Fair-Rite to be the main source of just about
everything made of ferrite, and Jim mentions them several times in his
article. However, Fair-Rite's online catalog does not list them in
their toroid section, nor are they shown in their downloadable PDF catalog.

I'm pretty sure Amidon doesn't have them either. Where else can I
look? Any thoughts?

Thanks in advance

73,

Ken Alexander
VE3HLS

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Craig Smith

Re: Source for Type 31 Toroids

Hi Ken …

Just checked the Fair-rite website, and the type 31 cores are indeed there. But they aren't easy to find. You need to go to Products then Cable components then EMI suppression beads.

They have a wide variety of part numbers using type 31 material.

I buy mine from Mouser which has no minimum order quantities, good stocking, reasonable prices and wonderful delivery and service. I can't speak to their service to Canada. I've bought many different PNs of type 31 from them. After you find the PNs you are interested in from the Fair-rite site, do a search on those PNs in the Mouser site.

Have fun & 73
… Craig AC0DS

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Jim Brown-10

Re: Source for Type 31 Toroids

In reply to this post by Ken Alexander-2

On 2/10/2012 10:23 AM, Ken Alexander wrote:
> However, Fair-Rite's online catalog does not list them in
> their toroid section, nor are they shown in their downloadable PDF catalog.

They are there -- you have to look under the EMC products, not inductive
products. Same thing, but the inductive parts are tested for inductance
at low frequencies while the EMC parts are tested for impedance at
higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
part numbers and a list of known good sources. Off the top of my head,
Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
pays to shop around, and to buy in quantity, combining quantities with
your ham neighbors and clubs.

73, Jim K9YC
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Jack Smith-6

Re: Source for Type 31 Toroids

In reply to this post by Ken Alexander-2

Kits and Parts stocks some 31 cores. http://www.kitsandparts.com/

Mouser carries the large 2.4" diameter 31 material core, a bit cheaper
than Kits and Parts. 623-2631803802

If you search Mouser for part numbers beginning with 2631 and
Manufacturer = Fair=Rite you will find several other sizes of 31
material cores available.

Jack K8ZOA

On 2/10/2012 1:23 PM, Ken Alexander wrote:

> I have some interference problems with my receivers and have been
> reading Jim K9YCs excellent article on the subject. It sounds like type
> 31 ferrite toroids will be the answer to some of my problems and I'm
> interestedin buying some.
>
> I had always considered Fair-Rite to be the main source of just about
> everything made of ferrite, and Jim mentions them several times in his
> article. However, Fair-Rite's online catalog does not list them in
> their toroid section, nor are they shown in their downloadable PDF catalog.
>
> I'm pretty sure Amidon doesn't have them either. Where else can I
> look? Any thoughts?
>
> Thanks in advance
>
> 73,
>
> Ken Alexander
> VE3HLS
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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>

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Ken Alexander-2

Re: Source for Type 31 Toroids

In reply to this post by Jim Brown-10

Nope! I can't find what you're talking about. There's something wrong when someone have to provide a tutorial on how to navigate their website. Somebody should be thinking "maybe our website isn't that easy to use."

Anyway, never mind. I'll try Digi-Key , Mouser, etc.

Thanks Jim.

Ken

________________________________
From: Jim Brown <[hidden email]>
To: [hidden email]
Sent: Friday, February 10, 2012 2:01:22 PM
Subject: Re: [Elecraft] Source for Type 31 Toroids

On 2/10/2012 10:23 AM, Ken Alexander wrote:
> However, Fair-Rite's online catalog does not list them in
> their toroid section, nor are they shown in their downloadable PDF catalog.

They are there -- you have to look under the EMC products, not inductive
products. Same thing, but the inductive parts are tested for inductance
at low frequencies while the EMC parts are tested for impedance at
higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
part numbers and a list of known good sources. Off the top of my head,
Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
pays to shop around, and to buy in quantity, combining quantities with
your ham neighbors and clubs.

73, Jim K9YC
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Ken Alexander-2

Re: Source for Type 31 Toroids

In reply to this post by Craig Smith

Son of a gun! I was right there but I was fooled by the illustration of the bead. I left the page when I thought I was looking at beads and never did check the dimensions, but there they are!

Thanks Craig!

73 - Ken

________________________________
From: Craig Smith <[hidden email]>
To: Ken Alexander <[hidden email]>
Cc: [hidden email]
Sent: Friday, February 10, 2012 1:54:13 PM
Subject: Re: [Elecraft] Source for Type 31 Toroids

Hi Ken …

Just checked the Fair-rite website, and the type 31 cores are indeed there. But they aren't easy to find. You need to go to Products then Cable components then EMI suppression beads.

They have a wide variety of part numbers using type 31 material.

I buy mine from Mouser which has no minimum order quantities, good stocking, reasonable prices and wonderful delivery and service. I can't speak to their service to Canada. I've bought many different PNs of type 31 from them. After you find the PNs you are interested in from the Fair-rite site, do a search on those PNs in the Mouser site.

Have fun & 73
… Craig AC0DS
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K6LMP

Re: Source for Type 31 Toroids

Amidon also carries a wide range of beads made from 31 Material. Specifically, 13 round wire type beads and 12 snap-on beads, with prices ranging from 75 cents each to about $20 each, depending on size.

You can order directly from www.amidon.com.

Lew K6LMP

On Feb 10, 2012, at 12:45 PM, Ken Alexander wrote:

> Son of a gun! I was right there but I was fooled by the illustration of the bead. I left the page when I thought I was looking at beads and never did check the dimensions, but there they are!
>
> Thanks Craig!
>
> 73 - Ken
>
>
>
> ________________________________
> From: Craig Smith <[hidden email]>
> To: Ken Alexander <[hidden email]>
> Cc: [hidden email]
> Sent: Friday, February 10, 2012 1:54:13 PM
> Subject: Re: [Elecraft] Source for Type 31 Toroids
>
> Hi Ken …
>
> Just checked the Fair-rite website, and the type 31 cores are indeed there. But they aren't easy to find. You need to go to Products then Cable components then EMI suppression beads.
>
> They have a wide variety of part numbers using type 31 material.
>
> I buy mine from Mouser which has no minimum order quantities, good stocking, reasonable prices and wonderful delivery and service. I can't speak to their service to Canada. I've bought many different PNs of type 31 from them. After you find the PNs you are interested in from the Fair-rite site, do a search on those PNs in the Mouser site.
>
> Have fun & 73
> … Craig AC0DS
> ______________________________________________________________
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> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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Craig Smith

Re: Source for Type 31 Toroids

In reply to this post by Ken Alexander-2

Good Deal Ken. Also they have a selection of type 31 clamp-on cores listed under Snap-Its.

73 Craig AC0DS

On 10, Feb2012, at 1:45 PM, Ken Alexander wrote:

> Son of a gun! I was right there but I was fooled by the illustration of the bead. I left the page when I thought I was looking at beads and never did check the dimensions, but there they are!
>
>
>

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Eugene Balinski

Re: Source for Type 31 Toroids

In reply to this post by K6LMP

I have used Amidon products in the past. Good quality.

73
Gene K1NR

On Fri, 10 Feb 2012 13:01:55 -0800
Lew Phelps K6LMP <[hidden email]> wrote:

> Amidon also carries a wide range of beads made from 31
> Material. Specifically, 13 round wire type beads and 12
> snap-on beads, with prices ranging from 75 cents each to
> about $20 each, depending on size.
>
> You can order directly from www.amidon.com.
>
> Lew K6LMP
>
>
> On Feb 10, 2012, at 12:45 PM, Ken Alexander wrote:
>
> > Son of a gun! I was right there but I was fooled by
> the illustration of the bead. I left the page when I
> thought I was looking at beads and never did check the
> dimensions, but there they are!
> >
> > Thanks Craig!
> >
> > 73 - Ken
> >
> >
> >
> > ________________________________
> > From: Craig Smith <[hidden email]>
> > To: Ken Alexander <[hidden email]>
> > Cc: [hidden email]
> > Sent: Friday, February 10, 2012 1:54:13 PM
> > Subject: Re: [Elecraft] Source for Type 31 Toroids
> >
> > Hi Ken …
> >
> > Just checked the Fair-rite website, and the type 31
> cores are indeed there. But they aren't easy to find.
> You need to go to Products then Cable components then
> EMI suppression beads.
> >
> > They have a wide variety of part numbers using type 31
> material.
> >
> > I buy mine from Mouser which has no minimum order
> quantities, good stocking, reasonable prices and
> wonderful delivery and service. I can't speak to their
> service to Canada. I've bought many different PNs of
> type 31 from them. After you find the PNs you are
> interested in from the Fair-rite site, do a search on
> those PNs in the Mouser site.
> >
> > Have fun & 73
> > … Craig AC0DS
> >
>

______________________________________________________________

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> http://www.qsl.net/donate.html
>
>

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Craig Smith

Re: Source for Type 31 Toroids

In reply to this post by Craig Smith

Fair-rite

On 10, Feb2012, at 2:10 PM, Dick Stein wrote:

> Hi Craig: Who is the vendor "They" when you say "they have a selection"? Dick, K2ZR/4

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Jim Brown-10

Re: Source for Type 31 Toroids

In reply to this post by K6LMP

On 2/10/2012 1:01 PM, Lew Phelps K6LMP wrote:
> Amidon also carries a wide range of beads made from 31 Material. Specifically, 13 round wire type beads and 12 snap-on beads, with prices ranging from 75 cents each to about $20 each, depending on size.

Amidon is probably the most expensive place to buy this stuff. All of
those sources I mentioned, as well as Mouser, are MUCH cheaper.

73, Jim K9YC
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Byron Servies

Re: Source for Type 31 Toroids

In reply to this post by Jim Brown-10

I have purchased boxes of type 31 from Kreiger. They are fast, and
their web site was recently re-done to be much easier to navigate.

73, Byron N6NUL

On Fri, Feb 10, 2012 at 11:01 AM, Jim Brown <[hidden email]> wrote:

> On 2/10/2012 10:23 AM, Ken Alexander wrote:
>> However, Fair-Rite's online catalog does not list them in
>> their toroid section, nor are they shown in their downloadable PDF catalog.
>
> They are there -- you have to look under the EMC products, not inductive
> products. Same thing, but the inductive parts are tested for inductance
> at low frequencies while the EMC parts are tested for impedance at
> higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
> part numbers and a list of known good sources. Off the top of my head,
> Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
> pays to shop around, and to buy in quantity, combining quantities with
> your ham neighbors and clubs.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

--
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org
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Ken Alexander-2

Re: Source for Type 31 Toroids

In reply to this post by Eugene Balinski

I have always bought from Amidon before. It sounds like they're a major distributor though, and not the manufacturer, which is Fair-Rite, correct?

73 - Ken

________________________________
From: Eugene Balinski <[hidden email]>
To: Lew Phelps K6LMP <[hidden email]>; "[hidden email] List" <[hidden email]>
Sent: Friday, February 10, 2012 4:24:53 PM
Subject: Re: [Elecraft] Source for Type 31 Toroids

I have used Amidon products in the past. Good quality.

73
Gene K1NR

On Fri, 10 Feb 2012 13:01:55 -0800
Lew Phelps K6LMP <[hidden email]> wrote:

______________________________________________________________

Jim Brown-10

Re: Source for Type 31 Toroids

In reply to this post by Ken Alexander-2

On 2/10/2012 11:35 AM, Ken Alexander wrote:
> Somebody should be thinking "maybe our website isn't that easy to use."

It's designed for engineers who are looking for a wide variety of
ferrite parts for a wide variety of uses. From where I sit, Fair-Rite
has by far the best technical website I've ever seen, and nothing else
I've seen in the last 30 years is close. Their published data is 100
times more detailed and informative than any of their competitors. A lot
of what I know about ferrite materials I've learned by studying their
published data. To get as much and as good data as theirs you've got to
go back at least three decades to publications like the huge data books
published by companies like National, Motorola, GE, Fairchild, and RCA
for their semiconductors and tubes, and Electro-Voice for their
microphones and loudspeakers.

Historically, Fair-Rite has also very good about supplying engineering
samples for those doing real design work. When I first began the
studies that led to all of the work I've published, Fair-Rite provided
me with hundreds of samples of several dozen parts I requested, never
asking anything beyond the normal questions a regional rep would ask.
It's paid off for them -- the #31 toroids EXIST because I asked for
them, and thanks at least in part to the work I've published on using
multi-turn chokes, the #31 material has replaced older materials for
suppression at MF and HF.

73, Jim Brown K9YC
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rlindzen

Re: Source for Type 31 Toroids

In reply to this post by Byron Servies

What is the URL for Kreiger?

73, Dick WO1I

At 10:34 PM 2/10/2012, Byron Servies wrote:

>I have purchased boxes of type 31 from Kreiger. They are fast, and
>their web site was recently re-done to be much easier to navigate.
>
>73, Byron N6NUL
>
>On Fri, Feb 10, 2012 at 11:01 AM, Jim Brown <[hidden email]> wrote:
> > On 2/10/2012 10:23 AM, Ken Alexander wrote:
> >> However, Fair-Rite's online catalog does not list them in
> >> their toroid section, nor are they shown in their downloadable
> PDF catalog.
> >
> > They are there -- you have to look under the EMC products, not inductive
> > products. Same thing, but the inductive parts are tested for inductance
> > at low frequencies while the EMC parts are tested for impedance at
> > higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
> > part numbers and a list of known good sources. Off the top of my head,
> > Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
> > pays to shop around, and to buy in quantity, combining quantities with
> > your ham neighbors and clubs.
> >
> > 73, Jim K9YC
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
>
>
>
>--
>- Northern California Contest Club
>- CU in the 2012 Cal QSO Party 6-7 Oct 2012
>- www.cqp.org
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Bob K6UJ

Re: Source for Type 31 Toroids

In reply to this post by Byron Servies

I have used W8DIZ for my torroids.
Check out his website and slide down to torroids, he carries a good inventory.
I think his prices are pretty good too.

http://www.partsandkits.com/

73,
Bob
K6UJ

On Feb 10, 2012, at 1:34 PM, Byron Servies wrote:

> I have purchased boxes of type 31 from Kreiger. They are fast, and
> their web site was recently re-done to be much easier to navigate.
>
> 73, Byron N6NUL
>
> On Fri, Feb 10, 2012 at 11:01 AM, Jim Brown <[hidden email]> wrote:
>> On 2/10/2012 10:23 AM, Ken Alexander wrote:
>>> However, Fair-Rite's online catalog does not list them in
>>> their toroid section, nor are they shown in their downloadable PDF catalog.
>>
>> They are there -- you have to look under the EMC products, not inductive
>> products. Same thing, but the inductive parts are tested for inductance
>> at low frequencies while the EMC parts are tested for impedance at
>> higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
>> part numbers and a list of known good sources. Off the top of my head,
>> Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
>> pays to shop around, and to buy in quantity, combining quantities with
>> your ham neighbors and clubs.
>>
>> 73, Jim K9YC
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
> --
> - Northern California Contest Club
> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
> - www.cqp.org
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Byron Servies

Re: Source for Type 31 Toroids

In reply to this post by rlindzen

Sorry, I spelled their name wrong:

http://www.kregercomponents.com/

are the folks I have used. Their site will now tell you how many are
in a factory box, too, which as Jim K9YC recommends is a good way to
limit breakage. They do a very good job packing smaller orders, too,
though.

73, Byron N6NUL

On Fri, Feb 10, 2012 at 1:42 PM, Dick Lindzen <[hidden email]> wrote:

> What is the URL for Kreiger?
>
> 73, Dick WO1I
>
>
> At 10:34 PM 2/10/2012, Byron Servies wrote:
>>
>> I have purchased boxes of type 31 from Kreiger. They are fast, and
>> their web site was recently re-done to be much easier to navigate.
>>
>> 73, Byron N6NUL
>>
>> On Fri, Feb 10, 2012 at 11:01 AM, Jim Brown <[hidden email]>
>> wrote:
>> > On 2/10/2012 10:23 AM, Ken Alexander wrote:
>> >> However, Fair-Rite's online catalog does not list them in
>> >> their toroid section, nor are they shown in their downloadable PDF
>> >> catalog.
>> >
>> > They are there -- you have to look under the EMC products, not inductive
>> > products. Same thing, but the inductive parts are tested for inductance
>> > at low frequencies while the EMC parts are tested for impedance at
>> > higher frequencies. See Appendix One of the RFI tutorial for Fair-Rite
>> > part numbers and a list of known good sources. Off the top of my head,
>> > Allied, Newark, Digikey, Kreiger, Lodestone Pacific come to mind. It
>> > pays to shop around, and to buy in quantity, combining quantities with
>> > your ham neighbors and clubs.
>> >
>> > 73, Jim K9YC
>> > ______________________________________________________________
>> > Elecraft mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:[hidden email]
>> >
>> > This list hosted by: http://www.qsl.net
>> > Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>>
>> --
>> - Northern California Contest Club
>> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
>> - www.cqp.org
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
>

Jim Brown-10

Re: Source for Type 31 Toroids

In reply to this post by Ken Alexander-2

On 2/10/2012 1:39 PM, Ken Alexander wrote:
> I have always bought from Amidon before. It sounds like they're a major distributor though, and not the manufacturer, which is Fair-Rite, correct?

Amidon does not make this stuff. They are a distributor of Fair-Rite and
some other manufacturers, and NOT a good one. I'd bet there's no one
there who has a clue about anything technical. There USED to be a ham
there whose name was Amidon, but he's LONG LONG gone, and any technical
data there is a leftover from his days. They are selling now whatever
they sold then, for WILDLY high mark-ups as compared to most others.

I recently bought some transistors and a few small kits from W8DIZ
(preamps for use with Beverages and small voltage regulators). Fair
prices for what I bought, good service, and the kits were nicely done.
For toroids though I would go to the big guys -- it would be tough for
him to buy in enough quantity to offer good prices except for the few
coils used in his kits.

73, Jim K9YC.
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k6dgw

Re: Source for Type 31 Toroids

On 2/10/2012 2:05 PM, Jim Brown wrote:
> On 2/10/2012 1:39 PM, Ken Alexander wrote:

> Amidon does not make this stuff. They are a distributor of Fair-Rite
> and some other manufacturers, and NOT a good one. I'd bet there's no
> one there who has a clue about anything technical. There USED to be a
> ham there whose name was Amidon, but he's LONG LONG gone, and any
> technical data there is a leftover from his days.

Many years ago [as in maybe 54], I needed a ferrite core for a 4:1
balun. DX Engineering hadn't been invented then. I drove over to
Amidon [N. Hollywood/Burbank-ish] which turned out to be a suburban
house. A fellow, who's name was Amidon opened the door, installed me in
a living room filled to the brim with all sorts of boxes and stuff,
rummaged around in a bedroom and finally came up with the toroid core.
He wanted a lot for the core, in fact more than the 16 year old had. He
finally asked me where I had come from, and when I told him S. Central
LA, he gave me the core.

The balun didn't work, probably because I wound it wrong. I'm really
surprised they are still in business.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

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gm3sek

Re: Source for Type 31 Toroids

Fred Jensen wrote:

>On 2/10/2012 2:05 PM, Jim Brown wrote:
>> On 2/10/2012 1:39 PM, Ken Alexander wrote:
>
>> Amidon does not make this stuff. They are a distributor of Fair-Rite
>> and some other manufacturers, and NOT a good one. I'd bet there's no
>> one there who has a clue about anything technical. There USED to be a
>> ham there whose name was Amidon, but he's LONG LONG gone, and any
>> technical data there is a leftover from his days.
>
>Many years ago [as in maybe 54], I needed a ferrite core for a 4:1
>balun. DX Engineering hadn't been invented then. I drove over to
>Amidon [N. Hollywood/Burbank-ish] which turned out to be a suburban
>house. A fellow, who's name was Amidon opened the door, installed me in
>a living room filled to the brim with all sorts of boxes and stuff,
>rummaged around in a bedroom and finally came up with the toroid core.
>He wanted a lot for the core, in fact more than the 16 year old had. He
>finally asked me where I had come from, and when I told him S. Central
>LA, he gave me the core.
>
>The balun didn't work, probably because I wound it wrong. I'm really
>surprised they are still in business.

Any company handling anonymous grey toroids needs to have perfect stock
control... and Amidon still don't. I was sold a large number of #31
toroids which turned out to be #43 material.

So if you do buy from Amidon, check the weight!

2631803802 = "FT240-31": 112-114g [1]
2643803802 = "FT240-43": 120-122g [1]
5961003801 = "FT240-61": 104-106g

Original data from G3TXQ, since verified from dependable suppliers.

[1] The Fair-Rite data sheet says "118.000g" for both of these cores,
but in fact the weights of #31 and #43 are distinctly different.

--

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek
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