Date   
Re: P6042 -- bad line cord

greenboxmaven
 

It is nice to hear from a kindred spirit! For many reasons, I always scrounged for and repaired the things I needed and wanted. Here in Syracuse, there is a large university and a small one as well. It can be quite rewarding to ramble through the neighborhoods surrounding them. I was able to obtain most of my needs this way because I can repair so many things. My first Tektronix scopes came from those sources, there were usually chances to find two or more of the same or very similar models to construct one good one from them all. In the mid 1970s, "5" series scopes were being replaced in labs and repair shops, so students often brought them "home", and then dumped them when they failed or their years ended. In 1973, color TVs were still too expensive for those starting out on their own. You could on occasion find a first generation color set for free, but usually the CRT or other critical components were failed or very poor. About that time, however, there was a very good alternative if you were a good technician and willing to do patient work. One major manufacturer use wiring with a fatal defect. The insulation would decompose under elevated temperatures and corrode the conductor inside the insulation. The ends of the wire and the insulation looked fine, but inside it was intermittent in conductivity or ultimately decayed to green powder. The sets were only a few years old, but owners disgusted by constant and unsuccessful trips to a repair shop would often sell them very cheaply or give them away. I got one, spent a week of evenings completely rewiring it, and was rewarded with an excellent color picture. I have seen this happen in some Tektronix TV studio equipment when a wiring harness was close to a large resistor. This was usually in crowded consoles in studios or in video tape recorders. Once the wiring was replaced and if possible re-routed, adding a fan or otherwise greatly improving ventilation in the console prevented future failures. Tektronix broadcast equipment isn't mentioned much here, probably because it is irrelevant with digital TV, but the relentless duty it survived is a good example of it's quality.

Bruce Gentry, KA2IVY

On 9/24/19 7:17 AM, Chuck Harris wrote:
In the days of my youth, I used to get many of
the necessities of life from the local dumpster.
Irons, ironing boards, TV's, microwaves, toaster
ovens, hair dryers, vacuum cleaners... stereos,
stuff like that. (no computers, they weren't yet
available to the masses.) I was in a college
town, so you could count on the students throwing
away enough to furnish an apartment every year...
if you weren't too fussy, and knew how to clean
and make repairs.

-Chuck Harris


sdturne@q.com wrote:
Oh, also, it looks like the problem is in or near the plug. I used some advanced probing techniques (really just a normal 10x probe held near the cord) to note that the 60 Hz AC waveform disappears nearly entirely past the plug, compared to a known good line cord that shows a waveform all the way down.

Sean

Re: TDS 694C EEprom and cal adjustment software

 

Hi George,

While it obviously won't be a perfect solution, I have saved off the cal constants from U1055 and U1056 from serial # B011111. Let me know if you want them, and I'll email them to you. Recommend using new parts and saving the old ones!

Jay

Re: 11801 NVRAM

Chuck Harris
 

As a former 80X86 developer, I can say that actually it
is quite common for every subroutine to have its own segment.
It is called the large model. It makes code easy to locate
anywhere in the memory map.

PC's often used the small or medium models, which would require
the data and code, to be in the same segment (small), or the
data and code to be in two segments (medium).

Back in the day, I wrote a program called EXEHEX.EXE, which
allowed you to take PCDOS code tools and put the result in EPROMS.

It is still out there somewhere in the ether... Simtel20 had it.

-Chuck Harris

Leo Bodnar wrote:

CSA803A has tonnes of inbuilt telecom eye-diagram masks, this was its USP for telecom industry (who always had money.)

Each pixel on the display has a deep accumulation bucket that you can see in graded mode but only fully appreciate by downloading the raw screen data.
What you see: http://www.leobodnar.com/files/CSA803A-screenshot.png
What it actually is: http://www.leobodnar.com/files/CSA803-graded.png
Isn't this almost analogue? http://www.leobodnar.com/files/CSA803-graded2.png

I have recently replaced CRT in my HP89410A with an LCD display. Might try the same trick with CSA803A when I get free time and be bored.

The hardware on all 11800 boards is i80186 so a cunning enthusiast can easily hack and play with the code as they please. The only problem is that every subroutine seems to use its own segment which is very unusual for PC style software.

Leo



Re: P6042 -- bad line cord

Chuck Harris
 

In the days of my youth, I used to get many of
the necessities of life from the local dumpster.
Irons, ironing boards, TV's, microwaves, toaster
ovens, hair dryers, vacuum cleaners... stereos,
stuff like that. (no computers, they weren't yet
available to the masses.) I was in a college
town, so you could count on the students throwing
away enough to furnish an apartment every year...
if you weren't too fussy, and knew how to clean
and make repairs.

One thing I came to notice is that power cords
break, and when they do, they always break in the
exact same way: the bundles of fine wires looked
like they were snipped off square with a shear...
only there was still insulation, so that would be
an amazing snip job, if it were possible.

What I figure happens is a weak strand breaks,
which increases the stress on the neighboring
strands, at the weakest point, which is right at
the break in the broken strand... So, as more
flexing occurs, another strand breaks at that weak
point, which further increases the motion there,
which breaks another strand, and on, and on, and
on, until the wire bundle has been sheared off
square, one strand at a time.

Finding the break in the two wire power cords was
easy, just stretch the cord, by bending it into a
flat curve, and the break will be where the insulation
stretches, and thins... because there is no copper
under it to keep it full diameter.

For sheathed power cords, you have to guess at
which end the break will be, and remove that end.
Then pull on the wires, hard, and the broken wire
will pull out of the insulation, revealing the nicely
squared off end, and the length to the break.

The location of the breaks would always be about 1/2
inch outside of clamp, in the strain reliefs, on the
hand held side of the cord...

-Chuck Harris


sdturne@q.com wrote:

Oh, also, it looks like the problem is in or near the plug. I used some advanced probing techniques (really just a normal 10x probe held near the cord) to note that the 60 Hz AC waveform disappears nearly entirely past the plug, compared to a known good line cord that shows a waveform all the way down.

Sean

Re: 11801 NVRAM

Leo Bodnar
 

CSA803A has tonnes of inbuilt telecom eye-diagram masks, this was its USP for telecom industry (who always had money.)

Each pixel on the display has a deep accumulation bucket that you can see in graded mode but only fully appreciate by downloading the raw screen data.
What you see: http://www.leobodnar.com/files/CSA803A-screenshot.png
What it actually is: http://www.leobodnar.com/files/CSA803-graded.png
Isn't this almost analogue? http://www.leobodnar.com/files/CSA803-graded2.png

I have recently replaced CRT in my HP89410A with an LCD display. Might try the same trick with CSA803A when I get free time and be bored.

The hardware on all 11800 boards is i80186 so a cunning enthusiast can easily hack and play with the code as they please. The only problem is that every subroutine seems to use its own segment which is very unusual for PC style software.

Leo

Re: 11801 NVRAM

 

I too considered buying that Ramco 11801B for about 1 atto-second at which point SWMBO muttered something along the lines of "no more kit"!

D.

Re: 11801 NVRAM

Tom Gardner
 

There's a 11801B up for auction in the UK on Oct 1st. Current bid price is £5. I was tempted, but then I thought of the weight and the length of my in-queue.

Ramco will pack and send, but I think it would be advisable to tell them how to pack such an item.

https://www.i-bidder.com/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10179/lot-26bab183-ff69-40aa-9f31-aace009f0b53
https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10179/lot-26bab183-ff69-40aa-9f31-aace009f0b53

Why am I not surprised the /tail/ end of that URL is identical!

TDS 694C EEprom and cal adjustment software

George Langston
 

I picked up a nice TDS694C at a gov't auction. It's different than almost all other TDS500/600/700 models in that it is a has 3GHz bandwidth, 10GS/s, and only 50 ohm input termination - no 1Megohm option. Initially the only problem it showed in the error log was an input overload on one channel: "input voltage spec has been exceeded on one channel causing termination resistor to overheat". That sounded like a simple matter of replacing a 50 ohm resistor so I pulled the A10 acq board and visually inspected and probed around with my Fluke 87V but found no issues. After I replaced the A10 Acq board I now get "FAIL ++ Processor", and "FAIL ++ Acquisition" on powerup screen. In System-> Cal menu, SPC shows "Fail", Voltage Ref, Freq Resp, and Pulse Trigger all report "initialize". It would appear that I somehow corrupted or completely lost the cal constants in eeprom. I've read that cal constants for later models such as this are stored in 24C02 eeproms and not the DS1486 or DS1250Y. I have a working GPIB interface for this scope but I don't know which adjustment software version to use for the TDS694C. I have the 700A, 700C, 700D, adjustment software but none of these include the TDS694C.

So, my questions are these:
1) Does anyone know the addresses of the two eeproms that store the cal constants? (so I can try to GPIB read them to see if they're empty).
2) Does anyone have Tek Adjustment software that includes the TDS694C?

Many thanks!

Re: P6042 -- bad line cord

Bob Albert
 

Cool!  Just cut off the plug and replace it.
Bob

On Monday, September 23, 2019, 08:18:16 PM PDT, <sdturne@q.com> wrote:

Oh, also, it looks like the problem is in or near the plug. I used some advanced probing techniques (really just a normal 10x probe held near the cord) to note that the 60 Hz AC waveform disappears nearly entirely past the plug, compared to a known good line cord that shows a waveform all the way down.

Sean

Re: 11801 NVRAM

Chuck Harris
 

For what it is worth, I copied the two NVRAM/smart sockets on
my TB board.

I know that my constants are useless to you, but it might help
you figure out where any factory constants live.

-Chuck Harris

Reginald Beardsley via Groups.Io wrote:

I'm having too much fun with mine to want to tear it apart. But when my 2nd one arrives I'll make a point of documenting as much as I can in the process of diagnosing and hopefully repairing it.

Have Fun!
Reg



Re: P6042 -- bad line cord

@0culus
 

Oh, also, it looks like the problem is in or near the plug. I used some advanced probing techniques (really just a normal 10x probe held near the cord) to note that the 60 Hz AC waveform disappears nearly entirely past the plug, compared to a known good line cord that shows a waveform all the way down.

Sean

Re: P6042 -- bad line cord

@0culus
 

Nevermind, I was able to positively ID it as a Heyco strain relief bushing. Seeing as they are still made, I'm just going to break it and replace it with either another one or something else depending on how I decide to redo the line cord.

Sean

Re: 11801 NVRAM

Reginald Beardsley
 

I'm having too much fun with mine to want to tear it apart. But when my 2nd one arrives I'll make a point of documenting as much as I can in the process of diagnosing and hopefully repairing it.

Have Fun!
Reg

Re: P6042 -- bad line cord

@0culus
 

On Sun, Sep 22, 2019 at 03:30 PM, Dwayne Reid wrote:


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
Did you get a chance to take a look?

Sean

Re: P6042 -- bad line cord

Peter Christie
 

In my experience, all of these particular composite cables will eventually
fail, after using a TDR to locate faults, (Breaks), on my P6042 head, and
repairing them, a subsequent vigorous manipulation of the cable would
induce another break.

After a some experimenting with several el' çheapo Chinese HDMI cables,
i eventually found one with quality suitable inner cables, 5 wires, 2 shielded,
and overall shielded, to do a replacement. Note: Not all HDMI cables are equal !.

This will hopefully give me another 10 / 20 years free of P6042 cable problems.

Kind Regards, Peter / VK5EM.
... -.-

Re: P6042 Repairing the Probe Cable (WAS: P6042 -- bad line cord)

fiftythreebuick
 

Hi Dennis-

I've done the "cut off the bad part and reconnect" repair and it worked fine. You're right, there is some touchy stuff there but it did work for me. I don't remember having those problems with melting/disintegrating wire.... Must have been lucky! As I recall, I was using very small diameter Low Melting Point solder by Edsyn and a Metcal fine point regulated iron.

Sorry it's giving you so much trouble. Hope you can find a solution!

Tom AE5I

On Sun, Sep 22, 2019 at 06:59 PM, Dennis Tillman W7PF wrote:


Hi Dwayne,

Your solution to use an HDMI cable as a substitute for the P6042 cable
sounds like a great idea. Before I do any more damage to my P6042s
(explanation follows) I would like to hear from anyone else that
successfully fixed the cable from the head first.

A year ago I mentioned to a friend, who has P6042s, that my P6042s were
becoming intermittent where the cable from the probe entered the P6042. He
said it was very easy to fix this by cutting off the cable at the chassis,
removing the piece inside the chassis, and soldering the remaining cable in
its place. That sounded really simple. What could possibly go wrong?

After trying this myself on the two P6042s I am absolutely certain he never
tried this himself. From personal experience I would advise anyone to avoid
doing this until you have no choice because your cable is so broken that the
P6042 will not work no matter how much you wiggle or push on the cable.

The cable has many conductors in it. To be flexible Tek chose to make six of
the conductors extremely fine. They are the critical AC and DC signal
carrying wires from the head. These wires are by far the finest wire I have
ever seen. Until now I have never found a wire that is impossible to work
on. I have many insulation stripping tools including wire wrap wire
strippers for #28 and #30 gauge wire, Thermal Strippers (required by manned
space missions I once worked on), Telephone linesman strippers, etc. The
insulation on these wires was so delicate that any heat from a thermal wire
stripper or tugging on the insulation with a mechanical wire stripper broke
the entire wire right off.

After a few hours of experimenting I discovered that the heat from a
soldering iron a few inches away from the wires would soften the insulation.
At last I thought I could proceed to tin these wires. The lowest heat that
melted the solder (eutectic 63/37) I use DISSOLVED the copper wire because
it was so thin. Another hour of failed experiments passed before I gave up
trying to tin the wires.

The last thing I could think of that might work was to apply a little solder
in the hole the old wire was soldered to. To do this I used the absolute
minimum temperature necessary to melt the eutectic solder I use. Once the
solder in the hole was melted I pushed an unstripped wire into it. The
insulation puddled on top of the solder so that automatically stripped the
insulation from the wire. After a few attempts I managed to get the copper
wire imbedded in the molten solder. Whether it was in good electrical
contact or just trapped in a blob of cold solder was unknown. This is not my
idea of how to connect a wire to a PC board but it was the best I could do.

After I finished replacing all of the cable wires I confirmed there was
continuity on each wire from inside the chassis to the probe head. My two
P6042s are now sitting under my desk. They never worked after I replaced the
cable. I despair every time I look at them that I ruined an incredibly
valuable instrument.

Dennis Tillman W7PF

-----Original Message-----
From: Dwayne Reid
Sent: Sunday, September 22, 2019 12:39 PM
Subject: Re: [TekScopes] P6042 -- bad line cord

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




--
Dennis Tillman W7PF
TekScopes Moderator

Re: 11801 NVRAM

Chuck Harris
 

I have now have hex files for the TB EPROMS.

TB (4.03):
160-6980-02, 160-6981-03, 160-6982-02, and 160-6983-03

As well as:

EXEC (4.05):
160-6978-08, 160-6979-08, 160-6984-08, 160-6985-08,
160-6984-08, 160-6985-08, 160-6986-08, 160-6987-08

Display? (4.00):
160-0459-01, 160-0459-02

I haven't done the ACQ1 and 2, as I don't know where
they are. Probably in the plugin cage... looking
sort of difficult to access.

I tried to find board numbers, but was not successful.
I can look again, if someone can tell me where they
can be found.

-Chuck Harris





Sergey Kubushyn wrote:

On Tue, 17 Sep 2019, Chuck Harris wrote:

Hi Sergey,

You sound like me... great ambition, limited time.
Eh... That't the only thing that is in very short supply, time... It is
something one can't buy :(

I have copied the display EPROMS, and the exec EPROMS.

I am not sure where the TB EPROMS are, but if they are
nestled up behind the sampling heads, I have no interest
in going there.

Re: P6042 Repairing the Probe Cable (WAS: P6042 -- bad line cord)

Dwayne Reid
 

Hi there, Dennis.

I have indeed successfully repaired my P6042 by cutting the original cable shorter. No question: this is a painful process but I **WAS** successful. I've actually had to do both ends of the cable (separate occasions) at both the probe as well as the chassis.

The sucky thing about re-terminating the original cable in the chassis is that you lose about eight inches from the cable. Doing the probe end costs about four inches or so.

I've had to do this either three or four times. It finally got to the point where the probe cable was simply too short to be useful.

I use Metcal soldering equipment with 700F tips (sttc-126) - this may be the reason that I didn't have any problems with the conductors dissolving like you mentioned. Although I also have thermal strippers here (Teledyne Strip-All), I don't recall that I needed to use them for the repairs. My recollection is that I used Miller 101S mechanical strippers - I replace these often when the stripping notches get dull.

If you do want to try using the thermal strippers, use it to just melt the insulation. Then use something like the Miller 101 strippers to actually remove the insulation.

The most painful part of the process is dealing with the tight spaces inside the main unit. Repairing the probe was easy - just be careful not to lose the tiny ball-bearing that wants to go wandering off when you disassemble the probe.

Do give it a try again. Make sure that you actually have a couple of hours where you won't be interrupted and when you aren't tired.

dwayne

At 07:59 PM 9/22/2019, Dennis Tillman W7PF wrote:
Hi Dwayne,

Your solution to use an HDMI cable as a substitute for the P6042 cable
sounds like a great idea. Before I do any more damage to my P6042s
(explanation follows) I would like to hear from anyone else that
successfully fixed the cable from the head first.

A year ago I mentioned to a friend, who has P6042s, that my P6042s were
becoming intermittent where the cable from the probe entered the P6042. He
said it was very easy to fix this by cutting off the cable at the chassis,
removing the piece inside the chassis, and soldering the remaining cable in
its place. That sounded really simple. What could possibly go wrong?

After trying this myself on the two P6042s I am absolutely certain he never
tried this himself. From personal experience I would advise anyone to avoid
doing this until you have no choice because your cable is so broken that the
P6042 will not work no matter how much you wiggle or push on the cable.

The cable has many conductors in it. To be flexible Tek chose to make six of
the conductors extremely fine. They are the critical AC and DC signal
carrying wires from the head. These wires are by far the finest wire I have
ever seen. Until now I have never found a wire that is impossible to work
on. I have many insulation stripping tools including wire wrap wire
strippers for #28 and #30 gauge wire, Thermal Strippers (required by manned
space missions I once worked on), Telephone linesman strippers, etc. The
insulation on these wires was so delicate that any heat from a thermal wire
stripper or tugging on the insulation with a mechanical wire stripper broke
the entire wire right off.

After a few hours of experimenting I discovered that the heat from a
soldering iron a few inches away from the wires would soften the insulation.
At last I thought I could proceed to tin these wires. The lowest heat that
melted the solder (eutectic 63/37) I use DISSOLVED the copper wire because
it was so thin. Another hour of failed experiments passed before I gave up
trying to tin the wires.

The last thing I could think of that might work was to apply a little solder
in the hole the old wire was soldered to. To do this I used the absolute
minimum temperature necessary to melt the eutectic solder I use. Once the
solder in the hole was melted I pushed an unstripped wire into it. The
insulation puddled on top of the solder so that automatically stripped the
insulation from the wire. After a few attempts I managed to get the copper
wire imbedded in the molten solder. Whether it was in good electrical
contact or just trapped in a blob of cold solder was unknown. This is not my
idea of how to connect a wire to a PC board but it was the best I could do.

After I finished replacing all of the cable wires I confirmed there was
continuity on each wire from inside the chassis to the probe head. My two
P6042s are now sitting under my desk. They never worked after I replaced the
cable. I despair every time I look at them that I ruined an incredibly
valuable instrument.

Dennis Tillman W7PF

-----Original Message-----
From: Dwayne Reid
Sent: Sunday, September 22, 2019 12:39 PM
Subject: Re: [TekScopes] P6042 -- bad line cord

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




--
Dennis Tillman W7PF
TekScopes Moderator

--
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

Finding Mains Cord Faults was P6042 -- bad line cord

Brian Symons
 

I am an electrician by trade & tech but long retired.
I did quite a lot of work for an appliance repair company - mainly vacuum cleaners & cleaning equipment.

Damaged mains cords was a really common problem & some of the items with retractable cords could take a fair bit of disassembling.
The old boss used to cut a short bit off the plug end first if the wiggle & flex test didn't help locate the problem.

I always had my trusted "Volt Stick" - test pencil that indicated mains voltage presence without actual contact.
That worked to show a break in the Active (Hot) conductor but the neutral conductor could be the fault.

I bought a double mains outlet with Double Pole switching that had connecting links between the two outlets & rewired the one side with reverse polarity - ie neutral to the active pin & active to the neutral pin.
I clearly marked the outlet with cross hatching & "Warning - Reverse Polarity"  "Test Only."
I also got another single outlet which was left unwired.

The test outlet & unwired outlet were fixed to the test bench.

The first test was always a good inspection of the item, check the eaarthing if it is an earther housing, & then a physical test of pulling the cord through your fingers to detect any cuts or kinks etc in the flex to ensure that it is safe to handle the flex
Pulling the cord through your fingers is far better than just looking for faults.

By plugging into the normally wired outlet we could test for a broken Active Wire by running the test pencil along the cord.

By Plugging into the reverse polarity outlet the neutral was now live (hot) so the test pencil would locate a break in the Neutral Wire.

But sometimes the faults was at the recoil unit so a set of "Fool Killer" or "Suicide Leads" - mains cord with proper fully insulated crocodile clips could be fitting inside the unit & fitting the plug into the unwired socket to keep the protruding plug pins that now are live safe.
An alternative - perhaps better - would be to buy one of the LOTO - Lock Out Tag Out hard plastic plug covers that use a padlock to lock a damaged item plug so that equipment can't be used until repaired.

Then the "Fool Killer" leads could be used to repeat the two tests with power from the opposite end of the lead.

This would locate the fault most of the time.

At home I have a foot switch for use at any time that I may wish to disconnect power quickly (such as when I use a Fool Killer lead) & I use RCD / Safety Switch / Earth Leakage protection on all my circuits.
I have 30mA protection on the house but a 10mA Outlet on the bench.

My shed bench also has a trip cord switch used on conveyor belts with the cord along the front of the bench so that pushing on it cuts all power.
I got a few of those switches cheap on eBay once & since I normally work alone I decided it couldn't hurt to use one.

I also normally have a lead with stripped ends with some WAGO 222 connectors on it.
The WAGO 222 connectors are used for permanent wiring connections & I believe they are even rated for mines use.
They have a lever action which makes it really quick & easy to use when you wish to test something with wire ends.
One big advantage is the connector will safely & firmly hold a wide range of wire sizes.
The same connector can be used to hold a 2.5mm CSA (Cross Section Area) wire in one tunnel & a single strand from a 7 strand 1.5mm CSA will be kept so firmly in the next tunnel that the strand will break before it will slip.

The WAGO connectors are so quick & easy to use that you will use them first & avoid the tendency to be lazy & use a Fool Killer lead to test something withe wire ends on it.

Re: P6042 -- bad line cord

Colin Herbert
 

Hi Dennis,
That is exactly what I received too and on both occasions.
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dennis Tillman W7PF
Sent: 22 September 2019 23:43
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.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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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








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Dennis Tillman W7PF
TekScopes Moderator