Topics

P6042 -- bad line cord

@0culus
 

Hi all,

Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.

Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.

Thanks,

Sean

Bob Albert
 

Teardown: The Tektronix P6042 current probe is a classic

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Teardown: The Tektronix P6042 current probe is a classic

Paul Rako

The Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui...
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On Saturday, September 21, 2019, 08:49:45 PM PDT, sdturne@q.com <sdturne@q.com> wrote:

Hi all,

Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.

Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.

Thanks,

Sean

@0culus
 

Interesting article, but I guess I should rephrase this...anyone got a DEAD P6042 that I could get the line cord out of?

Sean

Bob Albert
 

I used to have one but the jaws got messed up and I sold it to some guy who wanted a shot at repairing it.  I have no idea what he did with it.
I had built a power supply that was entirely adequate.  But I don't remember anything about it.
Bob

On Saturday, September 21, 2019, 09:09:41 PM PDT, <sdturne@q.com> wrote:

Interesting article, but I guess I should rephrase this...anyone got a DEAD P6042 that I could get the line cord out of?

Sean

@0culus
 

On Sat, Sep 21, 2019 at 09:15 PM, Bob Albert wrote:


I used to have one but the jaws got messed up and I sold it to some guy who
wanted a shot at repairing it.  I have no idea what he did with it.
I had built a power supply that was entirely adequate.  But I don't remember
anything about it.
Bob
Ahh, it's all good. The article you mentioned is a rather good read. Interesting that it manages to outperform the newer ones.

BTW, anyone can feel free to contact me off list if you happen to have anything available. Thanks!!

Sean

 

Hi Sean,
What article are you referring to?
A link to it would be appreciated.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of sdturne@q.com
Sent: Saturday, September 21, 2019 9:09 PM

Interesting article, but I guess I should rephrase this...anyone got a DEAD P6042 that I could get the line cord out of?

Sean




--
Dennis Tillman W7PF
TekScopes Moderator

Bob Albert
 

Teardown: The Tektronix P6042 current probe is a classic

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Teardown: The Tektronix P6042 current probe is a classic

Paul Rako

The Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui...
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On Sunday, September 22, 2019, 09:40:09 AM PDT, Dennis Tillman W7PF <@Dennis_Tillman_W7pF> wrote:

Hi Sean,
What article are you referring to?
A link to it would be appreciated.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of sdturne@q.com
Sent: Saturday, September 21, 2019 9:09 PM

Interesting article, but I guess I should rephrase this...anyone got a DEAD P6042 that I could get the line cord out of?

Sean




--
Dennis Tillman W7PF
TekScopes Moderator

Siggi
 

Probably this is the article <
https://www.edn.com/design/test-and-measurement/4442795/Teardown--The-Tektronix-P6042-current-probe-is-a-classic
?

On Sun, Sep 22, 2019 at 12:40 PM Dennis Tillman W7PF <@Dennis_Tillman_W7pF>
wrote:

Hi Sean,
What article are you referring to?
A link to it would be appreciated.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
sdturne@q.com
Sent: Saturday, September 21, 2019 9:09 PM

Interesting article, but I guess I should rephrase this...anyone got a
DEAD P6042 that I could get the line cord out of?

Sean




--
Dennis Tillman W7PF
TekScopes Moderator



@0culus
 

Yes, that is the article.

Sean

Dwayne Reid
 

Hi there, Sean.

When you said "bad line cord", I assumed that you meant the AC power cord. However, upon reading subsequent messages, I'm now guessing that you are talking about the cord between the current probe and the chassis.

I have a P6042 where the probe cable has died many times. I just kept cutting it shorter and shorter. However, it finally got to the point where I had to replace the cable.

I used a HDMI cable and cut the HDMI plugs off. Lots of individually-shielded pairs.

Working fine so far but I suspect that the particular HDMI cable that I chose is also not suited for continuous flexing.

Just a suggestion.

dwayne

At 09:49 PM 9/21/2019, sdturne@q.com wrote:

Hi all,

Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.

Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.

Thanks,

Sean
--
Dwayne Reid <dwayner@...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
780-489-3199 voice 780-487-6397 fax 888-489-3199 Toll Free
www.trinity-electronics.com
Custom Electronics Design and Manufacturing

@0culus
 

On Sun, Sep 22, 2019 at 12:38 PM, Dwayne Reid wrote:


Hi there, Sean.

When you said "bad line cord", I assumed that you meant the AC power cord.
However, upon reading subsequent messages, I'm now guessing that you are
talking about the cord between the current probe and the chassis.

I have a P6042 where the probe cable has died many times. I just kept cutting
it shorter and shorter. However, it finally got to the point where I had to
replace the cable.

I used a HDMI cable and cut the HDMI plugs off. Lots of individually-shielded
pairs.

Working fine so far but I suspect that the particular HDMI cable that I chose
is also not suited for continuous flexing.

Just a suggestion.

dwayne
The probe cord might be problematic, but the problem at hand here is indeed the AC line cord. Today I desoldered it and there is definitely no continuity on either hot, neutral, or ground. I cannot, however, seem to figure out how to actually get the cord out of the chassis. The little strain relief thing that attaches it to the chassis has resisted all my efforts so far.

Sean

Bob Albert
 

Before you work on the strain relief any more, put your capacitance bridge on the power cord to see which end is open.  Once you determine that, you can replace the connector or shorten the cable, etc.
You will measure around 2 pF across the end with the fault, and quite a bit more at the good end.
Your TDR pulser will do it too.
Bob

On Sunday, September 22, 2019, 02:31:49 PM PDT, <sdturne@q.com> wrote:

On Sun, Sep 22, 2019 at 12:38 PM, Dwayne Reid wrote:


Hi there, Sean.

When you said "bad line cord", I assumed that you meant the AC power cord.
However, upon reading subsequent messages, I'm now guessing that you are
talking about the cord between the current probe and the chassis.

I have a P6042 where the probe cable has died many times. I just kept cutting
it shorter and shorter. However, it finally got to the point where I had to
replace the cable.

I used a HDMI cable and cut the HDMI plugs off. Lots of individually-shielded
pairs.

Working fine so far but I suspect that the particular HDMI cable that I chose
is also not suited for continuous flexing.

Just a suggestion.

dwayne
The probe cord might be problematic, but the problem at hand here is indeed the AC line cord. Today I desoldered it and there is definitely no continuity on either hot, neutral, or ground. I cannot, however, seem to figure out how to actually get the cord out of the chassis. The little strain relief thing that attaches it to the chassis has resisted all my efforts so far.

Sean

Dwayne Reid
 

Hi there, Sean.

I'm not near my unit right now, but isn't it just a Heyco strain relief? There is a special pliers that squeezes the movable portion into the other half if so. I often fake it using small vise grips on the outside portion and needle-nose pliers on the inside portion.

But I could be mistaken. I'll have a look later (today, I hope).

dwayne

At 03:31 PM 9/22/2019, sdturne@q.com wrote:

The probe cord might be problematic, but the problem at hand here is indeed the AC line cord. Today I desoldered it and there is definitely no continuity on either hot, neutral, or ground. I cannot, however, seem to figure out how to actually get the cord out of the chassis. The little strain relief thing that attaches it to the chassis has resisted all my efforts so far.

Sean
--
Dwayne Reid <dwayner@...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
780-489-3199 voice 780-487-6397 fax 888-489-3199 Toll Free
www.trinity-electronics.com
Custom Electronics Design and Manufacturing

 

Hi Bob,
Something strange happened when I received a copy of your post to TekScopes.
What I received was the sentence "Teardown: The Tektronix P6042 current probe is a classic" followed by a seemingly random series of vertical separator symbols. Did anyone else get the same thing?
That's why I asked for a link to the article (which I have since received).
The exact same thing appears if you go to TekScopes and look at the message there.

Could you send me OFF LIST (dennis at ridesoft dot com) the original email you posted so maybe I can figure out if there is a problem with how Groups.io handled it. Also, what email app do you use.

Thanks, Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bob Albert via Groups.Io
Sent: Saturday, September 21, 2019 8:53 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] P6042 -- bad line cord

Teardown: The Tektronix P6042 current probe is a classic

|
|
|
| | |

|

|
|
| |
Teardown: The Tektronix P6042 current probe is a classic

Paul Rako

The Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui...
|

|

|





On Saturday, September 21, 2019, 08:49:45 PM PDT, sdturne@q.com <sdturne@q.com> wrote:

Hi all,

Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.

Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.

Thanks,

Sean








--
Dennis Tillman W7PF
TekScopes Moderator

TomC
 

Dennis,

I got the same garbled email as you got.

A search for "Tektronix P6042 current probe is a classic" got the EDN article as the first hit.

Tom

On 9/22/2019 3:42 PM, Dennis Tillman W7PF wrote:
Hi Bob,
Something strange happened when I received a copy of your post to TekScopes.
What I received was the sentence "Teardown: The Tektronix P6042 current probe is a classic" followed by a seemingly random series of vertical separator symbols. Did anyone else get the same thing?
That's why I asked for a link to the article (which I have since received).
The exact same thing appears if you go to TekScopes and look at the message there.
Could you send me OFF LIST (dennis at ridesoft dot com) the original email you posted so maybe I can figure out if there is a problem with how Groups.io handled it. Also, what email app do you use.
Thanks, Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bob Albert via Groups.Io
Sent: Saturday, September 21, 2019 8:53 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] P6042 -- bad line cord
Teardown: The Tektronix P6042 current probe is a classic
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| | |
|
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Teardown: The Tektronix P6042 current probe is a classic
Paul Rako
The Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui...
|
|
|
On Saturday, September 21, 2019, 08:49:45 PM PDT, sdturne@q.com <sdturne@q.com> wrote:
Hi all,
Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.
Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.
Thanks,
Sean

Jim Ford
 

Me, too.Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Dennis Tillman W7PF <@Dennis_Tillman_W7pF> Date: 9/22/19 3:42 PM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] P6042 -- bad line cord Hi Bob,Something strange happened when I received a copy of your post to TekScopes.What I received was the sentence "Teardown: The Tektronix P6042 current probe is a classic" followed by a seemingly random series of vertical separator symbols. Did anyone else get the same thing?That's why I asked for a link to the article (which I have since received).The exact same thing appears if you go to TekScopes and look at the message there.Could you send me OFF LIST (dennis at ridesoft dot com) the original email you posted so maybe I can figure out if there is a problem with how Groups.io handled it. Also, what email app do you use.Thanks, Dennis -----Original Message-----From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bob Albert via Groups.IoSent: Saturday, September 21, 2019 8:53 PMTo: TekScopes@...: Re: [TekScopes] P6042 -- bad line cord Teardown: The Tektronix P6042 current probe is a classic| | | |  |  | | || |  | Teardown: The Tektronix P6042 current probe is a classicPaul RakoThe Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui... | | |    On Saturday, September 21, 2019, 08:49:45 PM PDT, sdturne@q.com <sdturne@q.com> wrote: Hi all,Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms. Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway. Thanks,Sean-- Dennis Tillman W7PFTekScopes Moderator

@0culus
 

On Sun, Sep 22, 2019 at 02:40 PM, Bob Albert wrote:


Before you work on the strain relief any more, put your capacitance bridge on
the power cord to see which end is open.  Once you determine that, you can
replace the connector or shorten the cable, etc.
You will measure around 2 pF across the end with the fault, and quite a bit
more at the good end.
Your TDR pulser will do it too.
Bob
Hi Bob,

I unfortunately don't have any way to measure pF, only down to nF. I'll try TDR.

Sean

Glenn Little
 

He appears to have quoted a typical google books scan.


Glenn

On 9/22/2019 6:42 PM, Dennis Tillman W7PF wrote:
Hi Bob,
Something strange happened when I received a copy of your post to TekScopes.
What I received was the sentence "Teardown: The Tektronix P6042 current probe is a classic" followed by a seemingly random series of vertical separator symbols. Did anyone else get the same thing?
That's why I asked for a link to the article (which I have since received).
The exact same thing appears if you go to TekScopes and look at the message there.

Could you send me OFF LIST (dennis at ridesoft dot com) the original email you posted so maybe I can figure out if there is a problem with how Groups.io handled it. Also, what email app do you use.

Thanks, Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bob Albert via Groups.Io
Sent: Saturday, September 21, 2019 8:53 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] P6042 -- bad line cord

Teardown: The Tektronix P6042 current probe is a classic

|
|
|
| | |

|

|
|
| |
Teardown: The Tektronix P6042 current probe is a classic

Paul Rako

The Tektronix P6042 current probe, introduced in 1969, allows you to understand and troubleshoot reactive circui...
|

|

|





On Saturday, September 21, 2019, 08:49:45 PM PDT, sdturne@q.com <sdturne@q.com> wrote:
Hi all,

Among other things I bought at hamfest, I got a P6042 current probe that won't power on. I believe all that may be wrong with it is a bad line cord, as there's no continuity between chassis and earth. Also, the hot conductor is only putting out about 30Vrms.

Is there a recommended way to replace it with a better cord? It seems super tiny gauge anyway.

Thanks,

Sean







--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Bob Albert
 

You can measure small capacitance.  Whatever your means of measuring capacitance, put the smallest value you can measure on it and take a reading.  Then connect the power cord across that and measure again.  You may be able to see enough difference to determine whether you are adding 2 pF or 100 pF.
Bob

On Sunday, September 22, 2019, 04:37:36 PM PDT, <sdturne@q.com> wrote:

On Sun, Sep 22, 2019 at 02:40 PM, Bob Albert wrote:


Before you work on the strain relief any more, put your capacitance bridge on
the power cord to see which end is open.  Once you determine that, you can
replace the connector or shorten the cable, etc.
You will measure around 2 pF across the end with the fault, and quite a bit
more at the good end.
Your TDR pulser will do it too.
Bob
Hi Bob,

I unfortunately don't have any way to measure pF, only down to nF. I'll try TDR.

Sean

@0culus
 

On Sun, Sep 22, 2019 at 04:47 PM, Bob Albert wrote:


You can measure small capacitance.  Whatever your means of measuring
capacitance, put the smallest value you can measure on it and take a
reading.  Then connect the power cord across that and measure again.  You
may be able to see enough difference to determine whether you are adding 2 pF
or 100 pF.
Bob
OK. You mean across the neutral and hot conductors?

Sean