Date   

Re: Tek 2430 'scope

Denis Cobley <denis.cobley@...>
 

Hi Kevin
The whole board was replaced because the CCD's & Peak Detectors needed to be
matched to each other and the board to meet specs.
The CCD's were always on a restricted supply to a few sites world wide that
had the training and hardware / software to do the matching (and a stock of
parts to get the best match).
The only place you will find any parts is another 2430/A.
Regards
Denis

----- Original Message -----
From: "kevinjohn5889" <cq443@...>
To: <TekScopes@...>
Sent: Sunday, June 01, 2003 9:45 AM
Subject: [TekScopes] Tek 2430 'scope


Hi all,

I'm a new member of your group, joined a couple of weeks ago. I most
certainly enjoy reading about the old Tek scopes. My favorite, and
the one I was trained on as a junior engineer, was the 454. (545 a
bit before my time.)

Had an interesting problem on a 465B scope which I own, finally
traced to an emitter reistor in the Y-deflection amp board which
randomly varied from 690 to 700 or more ohms as soon as the scope was
powered. The sympton was jitter (1 or more divisions) on the trace.
I thought it was a most unusual fault for a resistor to exhibit.

I now have a 2430 which needs urgent repair as a technician thought
he could measure 500 v on Chan 1...

Big question is whether the hybrid ICs for this 'scope are still
available anywhere? The ICs are:

Chan2/Chan1
U320/U420 165 2235 02 Low Noise Vert Pre-amplifier
U340/U440 165 1215 01 Peak detector (not replacable order
the whole A10 board!)
U350/U450 165 2074 04 CCD array/Driver assebmbly
U150 155 0239 02 A/B Trigger
U100 155 0238 00 Ext Trig Pre-amp

I have the manual for the scope and the parts listing for the IC for
U340/U440 as shown above says to "replace the board A10". I get a
horrible feeling that these ICs are impossible to get. Before I
spend a lot of time troubleshooting this scope, anyone know about the
general availablity of these hybrids and why Tek would replace the
complete A10 board instead of just the hybrid?

Hope you very experienced guys can shed some light on this.

Kevin C.





Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/



Re: Tek 2465* ?

Denis Cobley <denis.cobley@...>
 

The "A" or early "B" versions.
They fixed the Horz output hybrid failures by rolling the part to an 02.
The later "B" series scopes had Maxtek hybrids and they have a much higher
failure rate.
Regards
Denis

----- Original Message -----
From: "kolesnik" <kolesnik@...>
To: "TekScopes" <TekScopes@...>
Sent: Sunday, June 01, 2003 2:35 AM
Subject: [TekScopes] Tek 2465* ?



Which of the 2465 models is most reliable or is there any difference?

tnx
hank wd5jfr







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File - Posting Rules

TekScopes@...
 

Please edit any posts/replies to the list to
minimize quoted material to that required for continuity.

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List replies go to the original sender by default.
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Those congesting the list with with either of the above may have
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If you do not wish to belong to TekScopes, you may
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or when reading messages. The group's home is at:

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Regards,
Michael Dunn
Listowner, TekScopes


Re: Tek 2430 'scope

zenith5106 <zenith@...>
 

--- In TekScopes@..., "kevinjohn5889" <cq443@n...> wrote:
Hi all,

I'm a new member of your group, joined a couple of weeks ago. I
most
certainly enjoy reading about the old Tek scopes. My favorite, and
the one I was trained on as a junior engineer, was the 454. (545 a
bit before my time.)

Had an interesting problem on a 465B scope which I own, finally
traced to an emitter reistor in the Y-deflection amp board which
randomly varied from 690 to 700 or more ohms as soon as the scope
was
powered. The sympton was jitter (1 or more divisions) on the
trace.
I thought it was a most unusual fault for a resistor to exhibit.

I now have a 2430 which needs urgent repair as a technician thought
he could measure 500 v on Chan 1...

Big question is whether the hybrid ICs for this 'scope are still
available anywhere? The ICs are:

Chan2/Chan1
U320/U420 165 2235 02 Low Noise Vert Pre-amplifier
U340/U440 165 1215 01 Peak detector (not replacable order
the whole A10 board!)
U350/U450 165 2074 04 CCD array/Driver assebmbly
U150 155 0239 02 A/B Trigger
U100 155 0238 00 Ext Trig Pre-amp

I have the manual for the scope and the parts listing for the IC
for
U340/U440 as shown above says to "replace the board A10". I get a
horrible feeling that these ICs are impossible to get. Before I
spend a lot of time troubleshooting this scope, anyone know about
the
general availablity of these hybrids and why Tek would replace the
complete A10 board instead of just the hybrid?

Hope you very experienced guys can shed some light on this.

Kevin C.
Kev,

These parts are long gone obsolete. You may be able to get used parts
pulled from someones scrapped scope. There should be a lot of them
out there with bad CCD's as the only fault. By far the most common
problem with those scopes were the CCD's. They came in six different
versions, -00 through -05 and are normally not interchangeable since
there were also other mods on the mainboard which I guess was the
main reason for replacing the board rather than separate hybrids.
Reliability increasing with the version number.
On your scope with one channel down you could start by swapping
hybrids between the channels and see where it changes. Prime suspects
ought to be the preamp and/or attenuator. The attenuators by the way,
even though they have different P/N's are identical except for that
the cable is dressed out on different sides which you can fix by
taking off the cover and dress the cable out on the opposite side.
One word of caution: Do NOT run this type of scope with the cover off
and without forced cooling to the CCD area. The CCD's are getting so
hot without cooling that if they weren't already bad you can kill
them in a short time. On newer models there were even a warning
sticker inside about this.
/Zenith


Re: Tek 2430 'scope

Chuanxiao Li \(Pholink\)
 

The 165-2235- 02 is $65 @ www.sphere.bc.ca/test/tek-parts/tekparts3.html
$50 @ www.markhannahsurplus.com/master.pdf


Re: 2465 series scopes and GPIB with Labview

Miroslav Pokorni
 

Talk to National Instrument and get driver for 2465. That would make capture
and control of your scope painless, you will not have to write program for
it, unless machine generated code is to slow for your application.

As owner of Labview you are entitled to support and get your money worth
from your purchase.

Regards

Miroslav Pokorni

----- Original Message -----
From: "tbfowler100" <tfowler@...>
To: <TekScopes@...>
Sent: Saturday, May 31, 2003 5:27 PM
Subject: [TekScopes] 2465 series scopes and GPIB with Labview


Does anyone have any experience using the 2465 series scopes with the
GPIB interface, under Labview? Specifically, can Labview capture
waveform display data, perhaps by intercepting HPGL output? Or is
there another way to capture waveform data?


2465 series scopes and GPIB with Labview

tbfowler100 <tfowler@...>
 

Does anyone have any experience using the 2465 series scopes with the
GPIB interface, under Labview? Specifically, can Labview capture
waveform display data, perhaps by intercepting HPGL output? Or is
there another way to capture waveform data?


Tek 2430 'scope

kevinjohn5889
 

Hi all,

I'm a new member of your group, joined a couple of weeks ago. I most
certainly enjoy reading about the old Tek scopes. My favorite, and
the one I was trained on as a junior engineer, was the 454. (545 a
bit before my time.)

Had an interesting problem on a 465B scope which I own, finally
traced to an emitter reistor in the Y-deflection amp board which
randomly varied from 690 to 700 or more ohms as soon as the scope was
powered. The sympton was jitter (1 or more divisions) on the trace.
I thought it was a most unusual fault for a resistor to exhibit.

I now have a 2430 which needs urgent repair as a technician thought
he could measure 500 v on Chan 1...

Big question is whether the hybrid ICs for this 'scope are still
available anywhere? The ICs are:

Chan2/Chan1
U320/U420 165 2235 02 Low Noise Vert Pre-amplifier
U340/U440 165 1215 01 Peak detector (not replacable order
the whole A10 board!)
U350/U450 165 2074 04 CCD array/Driver assebmbly
U150 155 0239 02 A/B Trigger
U100 155 0238 00 Ext Trig Pre-amp

I have the manual for the scope and the parts listing for the IC for
U340/U440 as shown above says to "replace the board A10". I get a
horrible feeling that these ICs are impossible to get. Before I
spend a lot of time troubleshooting this scope, anyone know about the
general availablity of these hybrids and why Tek would replace the
complete A10 board instead of just the hybrid?

Hope you very experienced guys can shed some light on this.

Kevin C.


A-B 2.5K Pot Tek P/N 311-0994-000

obbm_1939 <tlynne@...>
 

R7844 had an accident. The cause of the accident has been remedied,
BUT the physical state of the wipers was changed from solid to gaseous
on two intensity control pots, Allen-Bradley 2.5k carbon pots.
Tektronix part number on these is 311-0994-00. Anyone know or have
these for sale or trade or know suitable substitute source? I can
deal with mechanical modifications to the extent of some flexibility
in mounting and shaft length. Thanks in advance for the usual good
info and help. Bill Narby


Re: Oil Filled Capacitors

Miroslav Pokorni
 

Yes, Stan, I missed that Tektronix' cap. It kind of registered with me, but
I realized what it was only later on, after I sent mail. Craig mailed me and
expressed doubts that an oil cap would be used as a timing capacitor.

Most likely, the seller in that auction had a bunch of caps in steel cans,
Tektronix cap being painted in such a pretty color, might have been thrown
in as a prize. The guy might not be involved with electronics stuff at all,
he might be selling off things left by someone in family.

Chuck explained me at length construction of Black Beauties and it turns out
they were oil filled, but container was plastic. The Beauty was filled
through a copper tube at one end, and tube doubled as one electrode. After
filling the cap, lead wire was inserted in tube, crimped and soldered.
Re-heating that solder seal during instrument assembly would cause oil leak,
something like English cars, and Tektronix fought that problem by
heat-sinking the critical lead during assembly. Chuck says, he got that
story from Deanne Kidd.

Regards

Miroslav Pokorni

----- Original Message -----
From: "Stan & Patricia Griffiths" <w7ni@...>
To: "Miroslav Pokorni" <mpokorni2000@...>
Cc: "TekScopes" <TekScopes@...>
Sent: Friday, May 30, 2003 2:52 PM
Subject: Re: [TekScopes] Oil Filled Capacitors


At least one of the caps in that auction is a Tek timing capacitor and I
am
not sure Tek ever used oil in those or not. I never took one apart.

I have sometimes referred to "Black Beauty" caps as oil caps since the
actually have oil in them. Technically they may be "dry paper, treated
with
oil" but there is so much oil in them that it often leaks out by the wire
seals and gets all over the outside of the cap and sometimes drips onto
the
instrument chassis. It is hard for me to think of that as a "dry" cap . .
.

Stan
w7ni@...

----- Original Message -----
From: "Miroslav Pokorni" <mpokorni2000@...>
To: <TekScopes@...>
Sent: Wednesday, May 28, 2003 10:14 PM
Subject: [TekScopes] Oil Filled Capacitors


In several instances of discussion on this forum paper caps were called
'oil
caps'. In last case that I remember, Don wrote back and pointed out that
those caps were actually paper, treated with oil but dry paper caps.
There
is an auction on e bay for several oil caps with pretty good picture of
them; address is:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2534602284&category=4662

As picture shows, oil caps are enclosed in steel case, to contain oil,
and
usual purpose of those caps is phase correction (or motor start), where
considerable current is drawn through the cap.

Regards

Miroslav Pokorni






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http://docs.yahoo.com/info/terms/



Re: Source of connecters for 7L13 to TR502

david@...
 

Anyone know a source for the 6 pin connectors that are used to connect the
7L13 spectrum analyzer to the TR502 tracking generator?
Hi Dave,

The 7L13 connects to the TR502 with 2 SMA cables.

You only need the "logic cable" if you want to hook up a DC508A option 07
counter to read the 7L13 center frequency.

The part number for the cable is 012-0648-00, or see previous discussions
in the archives for sources of Lemo connectors.

David


Source of connecters for 7L13 to TR502

Dave Henderson <nr1dx@...>
 

Anyone know a source for the 6 pin connectors that are used to connect the 7L13 spectrum analyzer to the TR502 tracking generator?

Dave


Oil Filled Capacitors

daven9ooq <daven9ooq@...>
 

Hi All:
I been copying the mail and noted all the questions reguarding oil
filled capacitors, Transformers, and the like, Tek manufactured a lot
of their own parts. I been fortunate to have picked up the intermal
tek materials manual vol.3 1987 it's a very elaborate catalog listing
just about every material tektronix used in the manufacturing of
their test equipment. I thought I would list some of their lubricants
used for variouse purposes. I can't find any cross reference to what
materials were used for specific parts, But it does list very
specific charastics of just about every material used.

Beacon 325 grease..... used for switches
Dow corning 200..... silicone dielectric fluid
Dow corning 5 ......." "
Mobile oil type 45 Used for transformers
Lubriplate 14285 multipurpose lubricant
Lubriplate A type 105 " "
Thermalloy..... 251, and 249 Silicone grease for heatsinks
Ibm 23 grease............... general purpose.

Thease are just a few of the litings.
To clean cam switch contacts I'm told isoproply alcohol Wet heavy
card stock and carefully slide underneath the contacts untill clean
is the only recomended method as anything harsher may damage the
laminate.

hope this is helpful!
73's
Dave
N9OOQ


FOR "Dr M J Di Girolamo" DrD@adelpha.net RE: TEK 2445A - parts

Dragan Stojanovic <dragans@...>
 

Mail has returned. Sending you again via group. Sorry.



Hello Mike,

No, that's not me. I have been for the first time to USA, CA, just two weeks
ago. :-))

Regards,

Dragan (ex ET3YU) :-))





Hi. This is the qmail-send program at ian.ukinternetsites.com.

I'm afraid I wasn't able to deliver your message to the following addresses.

This is a permanent error; I've given up. Sorry it didn't work out.

<DrD@...>:

--- Below this line is a copy of the message.

Return-Path: <dragans@...>

Received: (qmail 29919 invoked from network); 31 May 2003 18:03:04 -0000

Received: from smtp5.hy.skanova.net (195.67.199.134)

by customers.webandemailforwarding.com with SMTP; 31 May 2003 18:03:04 -0000

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by smtp5.hy.skanova.net (8.12.9/8.12.9) with SMTP id h4VI4E0T016136

for <DrD@...>; Sat, 31 May 2003 20:04:21 +0200 (CEST)

From: "Dragan Stojanovic" <dragans@...>

To: "Dr M J Di Girolamo" DrD@...


TEK 2445A - parts

Dragan Stojanovic <dragans@...>
 

Hello,

I have finally determined bad IC U800 on my TEK 2445A. Chip is not available
any more. Everything else is in "like new" condition.

Instead to throw it to trash I would like to sell parts on very popular
prices.

Regards,

Dragan

p.s. I'm located in Sweden


Tek 2465* ?

kolesnik
 

Which of the 2465 models is most reliable or is there any difference?

tnx
hank wd5jfr


Re: Oil Filled Capacitors

Miroslav Pokorni
 

You surely fulled me, I thought you are a mutant power supply.
Thank you for lead on corona effects and new name of TRW capacitor division.
Would you happen to know what was name of that company before TRW bought
them; I do not think that division was home grown at TRW, they seemed to
preffer acquisitions.

Regards

Miroslav Pokorni

----- Original Message -----
From: "jbarnes" <jbarnes@...>
To: "TekScopes" <TekScopes@...>; "Craig Sawyers"
<c.sawyers@...>; "Miroslav Pokorni" <mpokorni2000@...>
Sent: Friday, May 30, 2003 4:43 PM
Subject: Re: [TekScopes] Re: Oil Filled Capacitors


Hi,
I am not really a high voltage power supply !!

I am a high voltage power supply engineer. I work for CPI designing power
supplies for Medical X-ray generators. These are up to 100kW, 150kV and
1000mA.
Some of my work can be seen at www.cpii.com/cmp
These incidently use resonant technology.

I learned about the corona effects from a company called ASC. This company
was TRW. They make and have made many custom capacitors for HP, Tek, Varian,
Fluke etc. They are generally white wrap and fill construction.

They explained the corona effects in capacitors to me. They have an
application note at:

http://www.ascapacitor.com/PDF/corona%20phenomena.pdf

Wima built their capacitors with two sections in series to help with the
self-healing properties. When one of the sections arcs the other still
presents impedance.

ASC has built some snubber capacitors for me that have four sections in
series to obtain an a.c. rating of 800 v rms. The dc. rating of these was
1600 v.

As someone pointed out the corona arises because the electric field is not
uniform in the area of a void or mismatched dielectric constants.

These comments on capacitors also apply to high voltage transformers. This
why vacumn impregnating is used.

I have done some work with solid dielectric materials, potting, matching
the dielectrics and preventing voids is quite a challenge.


Regards,


John Barnes

P.S. just got home from the Rochester Hamfest with a pile of 7K plugins to
work on.






---------- Original Message ----------------------------------
From: "Miroslav Pokorni" <mpokorni2000@...>
Reply-To: "Miroslav Pokorni" <mpokorni2000@...>
Date: Fri, 30 May 2003 02:42:39 -0700

I guess, it does not help, but then everything has a resonant frequency.
The
only way to cope with it, if you can not avoid operating at that
frequency,
is to make cap mechanically lossy so that Q factor is down in mud.

Possibly, this acoustical phenomena, together with high current through
cap,
made resonant power supplies pretty much disappear. The last one that I
have
seen was a Hewlett Packard unit that used a cap branded with their name,
what I guess was a custom cap.

There seems to be no such a thing as a simple component, there is only
the
simple demand.

Regards

Miroslav Pokorni

----- Original Message -----
From: "Craig Sawyers" <c.sawyers@...>
To: "TekScopes" <TekScopes@...>
Sent: Friday, May 30, 2003 12:27 AM
Subject: RE: [TekScopes] Re: Oil Filled Capacitors


Corona discharge would be pretty hard to induce at 200 Vac. You would
have
to hit frequency around cap's resonance
That reminds me of another failure mechanism - acoustic. Try the
following
experiment. Make a simple power amp for square waves with a couple of
transistors or FETS, driving +/- 30V (say). Connect capacitor from
output
to low impedance load to get a reasonable current flowing. Now sweep
an
audio generator.

Many capacitors howl like a banshee at particular frequencies where the
internal mechanics resonate. These are usually ones where the windings
inside are relatively "loose". Very tightly wound capacitors are very
quiet - but there are some real shocks out there when you try the
experiment
(like some respected 10kV polypropylene which were more like a
loudspeaker
than a capacitor).

Needless to say, such mechanical vibration does nothing to help the
reliability of the capacitor.

Craig





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Re: Oil Filled Capacitors

eboytoronto
 

Hi,
I am not really a high voltage power supply !!

I am a high voltage power supply engineer. I work for CPI designing power supplies for Medical X-ray generators. These are up to 100kW, 150kV and 1000mA.
Some of my work can be seen at www.cpii.com/cmp
These incidently use resonant technology.

I learned about the corona effects from a company called ASC. This company was TRW. They make and have made many custom capacitors for HP, Tek, Varian, Fluke etc. They are generally white wrap and fill construction.

They explained the corona effects in capacitors to me. They have an application note at:

http://www.ascapacitor.com/PDF/corona%20phenomena.pdf

Wima built their capacitors with two sections in series to help with the self-healing properties. When one of the sections arcs the other still presents impedance.

ASC has built some snubber capacitors for me that have four sections in series to obtain an a.c. rating of 800 v rms. The dc. rating of these was 1600 v.

As someone pointed out the corona arises because the electric field is not uniform in the area of a void or mismatched dielectric constants.

These comments on capacitors also apply to high voltage transformers. This why vacumn impregnating is used.

I have done some work with solid dielectric materials, potting, matching the dielectrics and preventing voids is quite a challenge.


Regards,


John Barnes

P.S. just got home from the Rochester Hamfest with a pile of 7K plugins to work on.

---------- Original Message ----------------------------------
From: "Miroslav Pokorni" <mpokorni2000@...>
Reply-To: "Miroslav Pokorni" <mpokorni2000@...>
Date: Fri, 30 May 2003 02:42:39 -0700

I guess, it does not help, but then everything has a resonant frequency. The
only way to cope with it, if you can not avoid operating at that frequency,
is to make cap mechanically lossy so that Q factor is down in mud.

Possibly, this acoustical phenomena, together with high current through cap,
made resonant power supplies pretty much disappear. The last one that I have
seen was a Hewlett Packard unit that used a cap branded with their name,
what I guess was a custom cap.

There seems to be no such a thing as a simple component, there is only the
simple demand.

Regards

Miroslav Pokorni

----- Original Message -----
From: "Craig Sawyers" <c.sawyers@...>
To: "TekScopes" <TekScopes@...>
Sent: Friday, May 30, 2003 12:27 AM
Subject: RE: [TekScopes] Re: Oil Filled Capacitors


Corona discharge would be pretty hard to induce at 200 Vac. You would
have
to hit frequency around cap's resonance
That reminds me of another failure mechanism - acoustic. Try the
following
experiment. Make a simple power amp for square waves with a couple of
transistors or FETS, driving +/- 30V (say). Connect capacitor from output
to low impedance load to get a reasonable current flowing. Now sweep an
audio generator.

Many capacitors howl like a banshee at particular frequencies where the
internal mechanics resonate. These are usually ones where the windings
inside are relatively "loose". Very tightly wound capacitors are very
quiet - but there are some real shocks out there when you try the
experiment
(like some respected 10kV polypropylene which were more like a loudspeaker
than a capacitor).

Needless to say, such mechanical vibration does nothing to help the
reliability of the capacitor.

Craig





Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/



Re: Oil Filled Capacitors

Stan & Patricia Griffiths <w7ni@...>
 

At least one of the caps in that auction is a Tek timing capacitor and I am
not sure Tek ever used oil in those or not. I never took one apart.

I have sometimes referred to "Black Beauty" caps as oil caps since the
actually have oil in them. Technically they may be "dry paper, treated with
oil" but there is so much oil in them that it often leaks out by the wire
seals and gets all over the outside of the cap and sometimes drips onto the
instrument chassis. It is hard for me to think of that as a "dry" cap . . .

Stan
w7ni@...

----- Original Message -----
From: "Miroslav Pokorni" <mpokorni2000@...>
To: <TekScopes@...>
Sent: Wednesday, May 28, 2003 10:14 PM
Subject: [TekScopes] Oil Filled Capacitors


In several instances of discussion on this forum paper caps were called
'oil
caps'. In last case that I remember, Don wrote back and pointed out that
those caps were actually paper, treated with oil but dry paper caps. There
is an auction on e bay for several oil caps with pretty good picture of
them; address is:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2534602284&category=4662

As picture shows, oil caps are enclosed in steel case, to contain oil, and
usual purpose of those caps is phase correction (or motor start), where
considerable current is drawn through the cap.

Regards

Miroslav Pokorni






Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/



Re: 7d01 with df1 garbled display

Miroslav Pokorni
 

Who was Lucas? Was that not British God of Darkness?

Regards

Miroslav Pokorni

----- Original Message -----
From: "Craig Sawyers" <c.sawyers@...>
To: <TekScopes@...>
Sent: Friday, May 30, 2003 11:34 AM
Subject: RE: [TekScopes] Re: 7d01 with df1 garbled display


The flat cables I
mentioned are the standard ones you'll find everywhere in older Tek
equipment. I put a picture at
http://w1.871.telia.com/~u87138090/Flatcable.jpg but it is very
difficult to visualize the difference with a picture. You'd really
need to see them both in real life and compare. The green is the bad
one and the blue is OK.
This is very reminiscent of the problem with one design of connector that
Lucas invented for Jaguar in the 1970s. The idea was that the cables were
crimped into either bullets or sockets, and these were assembled into an
array held in place by a moulded rubber housing.

Now although nominally gas tight, they progressively fail. Some stay OK,
but at random contacts can measure an ohm or two - upwards to open
circuit.
This can be disastrous with ampere currents in automotive circuits.
Because
housing is a moulded block around contacts it is impossible to solder the
crimp area - so the only way to solve the problem is to chop off the old
mating pair and replace with a good quality modern locking connector.

The failure mechanism might be to do with compounds in the rubber slowly
oxidising the copper, or it could be heat and humidity - or a combination.
Whatever, it is a sod to find (like the tek crimp problem).

Craig