Reply by Chris Jones ●January 10, 20222022-01-10
On 06/01/2022 07:23, Spehro Pefhany wrote:

> On Wed, 5 Jan 2022 14:43:36 -0500, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
>> Feedthrough caps have gotten stupid expensive, like $15 per pin.  There
>> are D sub connectors with built-in capacitance of up to about 47 nF, and
>>
>> I seem to recall seeing ferrite plates whose holes matched the D-sub
>> pattern, but can't find them.  A 9-pin one would be great.
> 
> Hi, Phil:-
> 
> Fair-Rite 2644236101 looks like what you want. Laird also may have
> something.


They mention high resistivity, but I couldn't see how conductive that 
material is. Hopefully not very.
Reply by Phil Hobbs ●January 6, 20222022-01-06
John Larkin wrote:

> On Wed, 5 Jan 2022 18:21:29 -0500, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
>> Gerhard Hoffmann wrote:
>>> Am 05.01.22 um 20:43 schrieb Phil Hobbs:
>>>> Feedthrough caps have gotten stupid expensive, like $15 per pin.
>>>> There are D sub connectors with built-in capacitance of up to about 47
>>>> nF, and
>>>>
>>>> I seem to recall seeing ferrite plates whose holes matched the D-sub
>>>> pattern, but can't find them.&nbsp; A 9-pin one would be great.
>>>>
>>>> What do you folks use for EMI filtering on connectors?
>>>
>>>
>>> <
>>> https://www.digikey.de/de/products/detail/tusonix-a-subsidiary-of-cts-electronic-components/2499-003-X5W0-502PLF/3116039
>>>   &nbsp; >
>>>
>>> I have bought this one 1.5 years ago for &euro; 6.
>>> I found that not exactly cheap for a ~M4 bolt with a
>>> tube capacitor inside.
>>>
>>> Now it is &euro; 21. But it was &euro;27 2 weeks ago when a customer
>>> wanted to buy them for the series.&nbsp; :-(
>>>
>>> I'm looking myself for something smaller and cheaper.
>>>
>>> cheers, Gerhard
>>
>> Thanks, all, that Fair-Rite part was what I was thinking of.  Forty
>> cents for 9 isolators is about the right price.
>>
>> Turns out that Tusonix sells some pretty nice solder-in and threaded
>> feedthroughs for a buck or so--see RF-microwave.com.
>>
> 
> So many RF boxes use these things for power input. You have to solder
> a wire outside onto the feedthru or something awkward like that. It's
> barbaric. Even tubes plugged into sockets.


I hear you.  But we do a lot of proof-of-concept demos for licensed 
design-in solutions.  Having stuff on the shelf that we can bolt 
together with no signal integrity worries is a huge win.

Once they get onto the customer's board, the signal integrity worries 
are much less serious--cap multipliers and board-level shields are 
better than good enough.

Cheers

Phil Hobbs


-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
Reply by John Larkin ●January 5, 20222022-01-05
On Wed, 5 Jan 2022 18:21:29 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:


>Gerhard Hoffmann wrote:
>> Am 05.01.22 um 20:43 schrieb Phil Hobbs:
>>> Feedthrough caps have gotten stupid expensive, like $15 per pin.  
>>> There are D sub connectors with built-in capacitance of up to about 47 
>>> nF, and
>>>
>>> I seem to recall seeing ferrite plates whose holes matched the D-sub 
>>> pattern, but can't find them.&#4294967295; A 9-pin one would be great.
>>>
>>> What do you folks use for EMI filtering on connectors?
>> 
>> 
>> < 
>> https://www.digikey.de/de/products/detail/tusonix-a-subsidiary-of-cts-electronic-components/2499-003-X5W0-502PLF/3116039 
>>  &#4294967295; >
>> 
>> I have bought this one 1.5 years ago for &#4294967295; 6.
>> I found that not exactly cheap for a ~M4 bolt with a
>> tube capacitor inside.
>> 
>> Now it is &#4294967295; 21. But it was &#4294967295;27 2 weeks ago when a customer
>> wanted to buy them for the series.&#4294967295; :-(
>> 
>> I'm looking myself for something smaller and cheaper.
>> 
>> cheers, Gerhard
>
>Thanks, all, that Fair-Rite part was what I was thinking of.  Forty 
>cents for 9 isolators is about the right price.
>
>Turns out that Tusonix sells some pretty nice solder-in and threaded 
>feedthroughs for a buck or so--see RF-microwave.com.
>
>Cheers
>
>Phil


So many RF boxes use these things for power input. You have to solder
a wire outside onto the feedthru or something awkward like that. It's
barbaric. Even tubes plugged into sockets.



-- 

If a man will begin with certainties, he shall end with doubts, 
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon
Reply by Phil Hobbs ●January 5, 20222022-01-05
Gerhard Hoffmann wrote:

> Am 05.01.22 um 20:43 schrieb Phil Hobbs:
>> Feedthrough caps have gotten stupid expensive, like $15 per pin.  
>> There are D sub connectors with built-in capacitance of up to about 47 
>> nF, and
>>
>> I seem to recall seeing ferrite plates whose holes matched the D-sub 
>> pattern, but can't find them.&nbsp; A 9-pin one would be great.
>>
>> What do you folks use for EMI filtering on connectors?
> 
> 
> < 
> https://www.digikey.de/de/products/detail/tusonix-a-subsidiary-of-cts-electronic-components/2499-003-X5W0-502PLF/3116039 
>  &nbsp; >
> 
> I have bought this one 1.5 years ago for &euro; 6.
> I found that not exactly cheap for a ~M4 bolt with a
> tube capacitor inside.
> 
> Now it is &euro; 21. But it was &euro;27 2 weeks ago when a customer
> wanted to buy them for the series.&nbsp; :-(
> 
> I'm looking myself for something smaller and cheaper.
> 
> cheers, Gerhard


Thanks, all, that Fair-Rite part was what I was thinking of.  Forty 
cents for 9 isolators is about the right price.

Turns out that Tusonix sells some pretty nice solder-in and threaded 
feedthroughs for a buck or so--see RF-microwave.com.

Cheers

Phil

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com
Reply by Gerhard Hoffmann ●January 5, 20222022-01-05
Am 05.01.22 um 20:43 schrieb Phil Hobbs:

> Feedthrough caps have gotten stupid expensive, like $15 per pin.&nbsp; There 
> are D sub connectors with built-in capacitance of up to about 47 nF, and
> 
> I seem to recall seeing ferrite plates whose holes matched the D-sub 
> pattern, but can't find them.&nbsp; A 9-pin one would be great.
> 
> What do you folks use for EMI filtering on connectors?



< 
https://www.digikey.de/de/products/detail/tusonix-a-subsidiary-of-cts-electronic-components/2499-003-X5W0-502PLF/3116039 
   >

I have bought this one 1.5 years ago for &euro; 6.
I found that not exactly cheap for a ~M4 bolt with a
tube capacitor inside.

Now it is &euro; 21. But it was &euro;27 2 weeks ago when a customer
wanted to buy them for the series.  :-(

I'm looking myself for something smaller and cheaper.

cheers, Gerhard
Reply by John Larkin ●January 5, 20222022-01-05
On Wed, 05 Jan 2022 15:23:40 -0500, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:


>On Wed, 5 Jan 2022 14:43:36 -0500, Phil Hobbs
><pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>>Feedthrough caps have gotten stupid expensive, like $15 per pin.  There 
>>are D sub connectors with built-in capacitance of up to about 47 nF, and
>>
>>I seem to recall seeing ferrite plates whose holes matched the D-sub 
>>pattern, but can't find them.  A 9-pin one would be great.
>
>Hi, Phil:- 
>
>Fair-Rite 2644236101 looks like what you want. Laird also may have
>something.  
>>
>>What do you folks use for EMI filtering on connectors?
>
>Feedthrough PI filters are very expensive but work nicely. 
>
>You can get military style connectors with some filtering built in,
>not cheap. 
>
>>Cheers
>>
>>Phil Hobbs


There are gender-changer-looking sorts of filter things that plug into
a d-sub.

-- 

If a man will begin with certainties, he shall end with doubts, 
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon
Reply by Spehro Pefhany ●January 5, 20222022-01-05
On Wed, 5 Jan 2022 14:43:36 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:


>Feedthrough caps have gotten stupid expensive, like $15 per pin.  There 
>are D sub connectors with built-in capacitance of up to about 47 nF, and
>
>I seem to recall seeing ferrite plates whose holes matched the D-sub 
>pattern, but can't find them.  A 9-pin one would be great.


Hi, Phil:- 

Fair-Rite 2644236101 looks like what you want. Laird also may have
something.  

>
>What do you folks use for EMI filtering on connectors?


Feedthrough PI filters are very expensive but work nicely. 

You can get military style connectors with some filtering built in,
not cheap. 


>Cheers
>
>Phil Hobbs

-- 
Best regards, 
Spehro Pefhany
Reply by Lasse Langwadt Christensen ●January 5, 20222022-01-05
onsdag den 5. januar 2022 kl. 20.43.48 UTC+1 skrev Phil Hobbs:

> Feedthrough caps have gotten stupid expensive, like $15 per pin. 


 https://www.surplussales.com/FEEDTHRUS/FTHOLEMNT3.HTML ?
https://www.alibaba.com/product-detail/M3-1000PF-Feedthrough-Capacitor_60409523377.html
https://de.aliexpress.com/item/1542421201.html


>There 
> are D sub connectors with built-in capacitance of up to about 47 nF, and 
> 
> I seem to recall seeing ferrite plates whose holes matched the D-sub 
> pattern, but can't find them. A 9-pin one would be great. 


https://www.digikey.at/en/products/detail/fair-rite-products-corp/2644236101/8593849 ?
Reply by Phil Hobbs ●January 5, 20222022-01-05
Feedthrough caps have gotten stupid expensive, like $15 per pin.  There 
are D sub connectors with built-in capacitance of up to about 47 nF, and

I seem to recall seeing ferrite plates whose holes matched the D-sub 
pattern, but can't find them.  A 9-pin one would be great.

What do you folks use for EMI filtering on connectors?

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com