Topics

Ferrite Beads in Tek Transistor Adapters


 

Tek uses ferrite beads in some of the transistor adapters they make for
their curve tracers. These beads are inserted in each (E, B, and C) lead of
the adapter. I always assumed the purpose of the beads is to prevent the
transistor from oscillating but I don't really know this for sure.

Does anyone know what frequency band Tek was concerned about or what ferrite
Tek used? There are many ferrite materials to choose from. The few I am
familiar with are FB-43, FB-61, FB-73, and FB-75B.

The 013-0128-00 adapter specifically for the 7CT1N and 5CT1N uses three
276-0507-00 "SHLD BEAD,ELEK:FERRITE" for example. But there is no more
information than this on the one or two page data sheet that comes with a
transistor adapter.

I would guess Tek would chose ferrite material that is intended for
relatively low frequencies (maximum resistive loss at 10MHz or less) but
that is only a guess.

Dennis Tillman W7pF


Dave Casey
 

Can you look up the bead in the Tek standard parts catalog and determine
its characteristics from there?

Dave Casey

On Sat, Jul 18, 2020 at 9:30 PM Dennis Tillman W7pF <@Dennis_Tillman_W7pF>
wrote:

Tek uses ferrite beads in some of the transistor adapters they make for
their curve tracers. These beads are inserted in each (E, B, and C) lead of
the adapter. I always assumed the purpose of the beads is to prevent the
transistor from oscillating but I don't really know this for sure.

Does anyone know what frequency band Tek was concerned about or what
ferrite
Tek used? There are many ferrite materials to choose from. The few I am
familiar with are FB-43, FB-61, FB-73, and FB-75B.

The 013-0128-00 adapter specifically for the 7CT1N and 5CT1N uses three
276-0507-00 "SHLD BEAD,ELEK:FERRITE" for example. But there is no more
information than this on the one or two page data sheet that comes with a
transistor adapter.

I would guess Tek would chose ferrite material that is intended for
relatively low frequencies (maximum resistive loss at 10MHz or less) but
that is only a guess.

Dennis Tillman W7pF




Chuck Harris
 

The purpose of the beads is to make the connections
to the transistors both high impedance, and lossy at
the frequencies the transistor might try to oscillate.

Any of the of the ferrite bead materials will do the job.

-Chuck Harris

Dennis Tillman W7pF wrote:

Tek uses ferrite beads in some of the transistor adapters they make for
their curve tracers. These beads are inserted in each (E, B, and C) lead of
the adapter. I always assumed the purpose of the beads is to prevent the
transistor from oscillating but I don't really know this for sure.

Does anyone know what frequency band Tek was concerned about or what ferrite
Tek used? There are many ferrite materials to choose from. The few I am
familiar with are FB-43, FB-61, FB-73, and FB-75B.

The 013-0128-00 adapter specifically for the 7CT1N and 5CT1N uses three
276-0507-00 "SHLD BEAD,ELEK:FERRITE" for example. But there is no more
information than this on the one or two page data sheet that comes with a
transistor adapter.

I would guess Tek would chose ferrite material that is intended for
relatively low frequencies (maximum resistive loss at 10MHz or less) but
that is only a guess.

Dennis Tillman W7pF




Glydeck
 

For curve tracer fixtures I’ve made I used these with good results.

https://www.allelectronics.com/item/fb-73/ferrite-bead-on-lead/1.html

Glydeck

On Jul 19, 2020, at 9:50 AM, Chuck Harris <cfharris@...> wrote:

The purpose of the beads is to make the connections
to the transistors both high impedance, and lossy at
the frequencies the transistor might try to oscillate.

Any of the of the ferrite bead materials will do the job.

-Chuck Harris

Dennis Tillman W7pF wrote:
Tek uses ferrite beads in some of the transistor adapters they make for
their curve tracers. These beads are inserted in each (E, B, and C) lead of
the adapter. I always assumed the purpose of the beads is to prevent the
transistor from oscillating but I don't really know this for sure.

Does anyone know what frequency band Tek was concerned about or what ferrite
Tek used? There are many ferrite materials to choose from. The few I am
familiar with are FB-43, FB-61, FB-73, and FB-75B.

The 013-0128-00 adapter specifically for the 7CT1N and 5CT1N uses three
276-0507-00 "SHLD BEAD,ELEK:FERRITE" for example. But there is no more
information than this on the one or two page data sheet that comes with a
transistor adapter.

I would guess Tek would chose ferrite material that is intended for
relatively low frequencies (maximum resistive loss at 10MHz or less) but
that is only a guess.

Dennis Tillman W7pF





Roy Thistle
 

On Sun, Jul 19, 2020 at 12:38 PM, Glydeck wrote:


I used these with good results.
WARNING: May cause cancer or reproductive harm?.. at least in the state of California?


Chuck Harris
 

Everything is known to cause cancer in the state of
California.... Makes me glad I don't live there.

-Chuck Harris

Roy Thistle wrote:

On Sun, Jul 19, 2020 at 12:38 PM, Glydeck wrote:


I used these with good results.
WARNING: May cause cancer or reproductive harm?.. at least in the state of California?




Carsten Bormann
 

On 2020-07-20, at 03:20, Chuck Harris <cfharris@...> wrote:

Everything is known to cause cancer in the state of
California.... Makes me glad I don't live there.
They say:


Why is this here?
As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.

As an example:
• ABS plastic contains styrene
• PVC wire insulation can contain Di(2-ethylhexyl)phthalate (DEHP)
• electrolytic capacitors can contain Ethylene glycol
• Brass can contain Lead
• flame retardant pc boards can contain Tetrabromobisphenol A (TBBPA)
• Aluminum alloys can contain Chromium

To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!


Typical cop-out created by non-thinking regulation.
But I generally agree with the advice not to try smoking ferrite beads.

Grüße, Carsten


Dave Seiter
 

As a former environmental compliance guy in CA, I can say that it's mind-numbingly inane. Everything is potentially toxic or dangerous- it's just a matter of quantity/frequency (drinking too much water can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc) 
At some point, all the warnings become meaningless, kind of like advertising (which I ignore and remove whenever possible).  The nanny state at it's finest, thanks mostly to lawyers...
OTOH, it might be nice if older Tek scopes had warnings about weight (don't try to pick up a 519 if your back has been acting up!)
-Dave

On Sunday, July 19, 2020, 06:35:20 PM PDT, Carsten Bormann <cabocabo@...> wrote:

On 2020-07-20, at 03:20, Chuck Harris <cfharris@...> wrote:

Everything is known to cause cancer in the state of
California.... Makes me glad I don't live there.
They say:


Why is this here?
As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.

As an example:
    • ABS plastic contains styrene
    • PVC wire insulation can contain Di(2-ethylhexyl)phthalate (DEHP)
    • electrolytic capacitors can contain Ethylene glycol
    • Brass can contain Lead
    • flame retardant pc boards can contain Tetrabromobisphenol A (TBBPA)
    • Aluminum alloys can contain Chromium

To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!


Typical cop-out created by non-thinking regulation.
But I generally agree with the advice not to try smoking ferrite beads.

Grüße, Carsten


Michael W. Lynch
 

On Fri, Jul 24, 2020 at 09:30 PM, Dave Seiter wrote:


I can say that it's mind-numbingly inane. Everything is potentially toxic or
dangerous- it's just a matter of quantity/frequency (drinking too much water
can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc)
This is why we have "Warning" labels on Preparation H that states "not to be taken orally".

--
Michael Lynch
Dardanelle, AR


Stephen
 

On Sat, Jul 25, 2020 at 03:11 AM, Michael W. Lynch wrote:

This is why we have "Warning" labels on Preparation H that states "not to be
taken orally".

--
Michael Lynch
Dardanelle, AR
😂😂😂


Glydeck
 

You should click on The link “Why is this here” on the All Electronics page. This would be the reality of good intentions gone wrong and ultimately becoming useless.

“As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.
To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!”

On Jul 25, 2020, at 7:11 AM, Michael W. Lynch via groups.io <mlynch003=yahoo.com@groups.io> wrote:

On Fri, Jul 24, 2020 at 09:30 PM, Dave Seiter wrote:


I can say that it's mind-numbingly inane. Everything is potentially toxic or
dangerous- it's just a matter of quantity/frequency (drinking too much water
can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc)
This is why we have "Warning" labels on Preparation H that states "not to be taken orally".

--
Michael Lynch
Dardanelle, AR



Chuck Harris
 

Votes have consequences.

Glydeck via groups.io wrote:

You should click on The link “Why is this here” on the All Electronics page. This would be the reality of good intentions gone wrong and ultimately becoming useless.

“As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.
To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!”
On Jul 25, 2020, at 7:11 AM, Michael W. Lynch via groups.io <mlynch003=yahoo.com@groups.io> wrote:

On Fri, Jul 24, 2020 at 09:30 PM, Dave Seiter wrote:


I can say that it's mind-numbingly inane. Everything is potentially toxic or
dangerous- it's just a matter of quantity/frequency (drinking too much water
can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc)
This is why we have "Warning" labels on Preparation H that states "not to be taken orally".

--
Michael Lynch
Dardanelle, AR





Glydeck
 

Chuck,

Totally agree! So does having or not having a basic education.

Staying on topic, the ferrite beads work well for building your own test fixtures.

George

On Jul 25, 2020, at 8:02 AM, Chuck Harris <cfharris@...> wrote:

Votes have consequences.

Glydeck via groups.io wrote:
You should click on The link “Why is this here” on the All Electronics page. This would be the reality of good intentions gone wrong and ultimately becoming useless.

“As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.
To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!”
On Jul 25, 2020, at 7:11 AM, Michael W. Lynch via groups.io <mlynch003=yahoo.com@groups.io> wrote:

On Fri, Jul 24, 2020 at 09:30 PM, Dave Seiter wrote:


I can say that it's mind-numbingly inane. Everything is potentially toxic or
dangerous- it's just a matter of quantity/frequency (drinking too much water
can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc)
This is why we have "Warning" labels on Preparation H that states "not to be taken orally".

--
Michael Lynch
Dardanelle, AR






 

This forum is all about classic Tektronix test equipment, its use, repair, and collecting.

This is not a forum about how California chooses to govern itself.

What California does or does not do is irrelevant to my original question about ferrites used in Tek Transistor adapters.

Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave Seiter
Sent: Friday, July 24, 2020 7:29 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Ferrite Beads in Tek Transistor Adapters

As a former environmental compliance guy in CA, I can say that it's mind-numbingly inane. Everything is potentially toxic or dangerous- it's just a matter of quantity/frequency (drinking too much water can kill you, you can be crushed by cabbages, anaphylaxis from cat hair, etc) At some point, all the warnings become meaningless, kind of like advertising (which I ignore and remove whenever possible). The nanny state at it's finest, thanks mostly to lawyers...
OTOH, it might be nice if older Tek scopes had warnings about weight (don't try to pick up a 519 if your back has been acting up!) -Dave
On Sunday, July 19, 2020, 06:35:20 PM PDT, Carsten Bormann <cabocabo@...> wrote:

On 2020-07-20, at 03:20, Chuck Harris <cfharris@...> wrote:

Everything is known to cause cancer in the state of California....
Makes me glad I don't live there.
They say:


Why is this here?
As of August 2018 the State of California has changed the requirements of the "Prop 65" law. We now must list on our website any possible chemicals the can cause cancer, birth defects or reproductive problem.

As an example:
• ABS plastic contains styrene
• PVC wire insulation can contain Di(2-ethylhexyl)phthalate (DEHP)
• electrolytic capacitors can contain Ethylene glycol
• Brass can contain Lead
• flame retardant pc boards can contain Tetrabromobisphenol A (TBBPA)
• Aluminum alloys can contain Chromium

To put it simply we are a small company and do not have the resources to test every single part, so we list every thing as hazardous. Please recycle all electronic parts responsibly and under no circumstance eat, drink or smoke these parts and wash your hands after touching!


Typical cop-out created by non-thinking regulation.
But I generally agree with the advice not to try smoking ferrite beads.

Grüße, Carsten








--
Dennis Tillman W7pF
TekScopes Moderator


Daveolla
 

At 09:11 AM 7/25/2020, you wrote:


This is why we have "Warning" labels on Preparation H that states "not to be taken orally".

--
Michael Lynch
Dardanelle, AR
You can take your Preparation H and shove it where the sun doesn't shine!

Dave