Date   

Re: Tektronix 2230

Dave Hills
 

Kapton is a high temperature film not really needed in a transformer.
Polyester or mylar film tape is quite adequate for this application. You will
often recognize it as yellow or white layer around modern transformer windings.
It is also able to stretch, which is useful for keeping windings in place. It has good
electrical characteristics, after all, it is used as the dielectric in many capacitors.
Of course you would want a non-metalized type.

Dave


Time and frequency items added to the on line stuff day event

 

I have added some time nuts items to the big annual stuff day (now on-line stuff season thanks to covid-19)
event at Sphere Research. The good part is now people far away get to snorkel though all the goodies.

There are some wonderful precision time code systems, using either internal crystal timebases or your own cesium reference to make beautiful 365 day clocks for your desk. One even has 2 linked remote stations (perfect for your own personal mission command console area). Look in in the time/frequency section. Also inexpensive high end hp precision counters (using 10811A's), see the hp section. Plus many other interesting items from white LED arrays to MC1496 mod/demod chips, great for making frequency doublers.

See everything here: https://www.sphere.bc.ca/test/stuffday.html
Maybe you will find something to take your mind off current events, and don't forget, we add
traditional stuff day free stuff to your order. Yes, we take requests for items you don't see.

all the best,
walter


Re: Tek 465 Turns on, No Dot, No Trace

Michael W. Lynch
 

On Sat, Jul 11, 2020 at 05:31 AM, Stephen wrote:


PS: Where do I lift the HV multiplier lug?
The HV Multiplier ground jumper should be located perpendicular to the outer edge of the A9 board, directly in front of the outer nylon nut that secures the HV Multiplier to the top of the A9 board and directly to the rear of P1445. The jumpers on all of my 4xx series scopes have had a plain white porcelain insulator. they could be just a plain wire on some scopes.

You can lift this and you should get some sort of dot or trace, as long as the rest of the circuit is working.

--
Michael Lynch
Dardanelle, AR


Re: Tek 465 Turns on, No Dot, No Trace

Michael W. Lynch
 

If you determine that your HV multiplier is defective, I have designed a 3D printed enclosure for the 465/475 which allows you to build your own HV multiplier which will fit into the original space. Original HV Multipliers are difficult to find and expensive to purchase. A home brewed version can be built with readily available parts for about $20-30 USD (probably less) and some of your time. I have built and fitted this part to my 465 (High SN) and it fits almost like the original. If interested, I am happy to supply more DETAILS and/or the STL file for the box upon request.

--
Michael Lynch
Dardanelle, AR


Re: Tek 465 Turns on, No Dot, No Trace

 

Some more info. Also a schematic link for the multiplier.

https://groups.io/g/TekScopes/topic/tek_465_multiplier/7658373?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,960,7658373

There is also some x-ray pictures of the multiplier around somewhere.

On 7/11/2020 5:01 PM, Stephen wrote:
On Sat, Jul 11, 2020 at 09:05 AM, Tom Miller wrote:

Ok, that sounds like the main problem. That HV multiplier is also used
in the 475 scope as well as the A and B versions. You might check with Q
service in Greece ( excellent to deal with) or search the part number
152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but
a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton
multiplier. Should be some info in the archives on groups.io. It is a
tripler so three caps and three diodes plus a 1-3 meg carbon comp
resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards
Hmmm... Does it have to be a carbon comp resistor?
I may try to build one using the existing enclosure. I hope it’s not dipped in epoxy.
Dinos at Q-Service is out of this part.
He’s really a very nice guy. I’ve dealt with him a few time, and talked to him on the phone last week.

Maybe I can just replace the parts inside. But I have the feeling it’s not gonna be that easy...
Plus, replacing that part apparently requires removing the entire board, which is a project in itself.
Grrrr...

PS: Were those cracklings sounds i heard to be expected? That startled me. I hope nothing was damaged...

--
This email has been checked for viruses by Avast antivirus software.
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Re: Tek 465 Turns on, No Dot, No Trace

 

Here is some info. I'll post some more as I find it.

http://w140.com/tekwiki/wiki/465/Repairs

On 7/11/2020 5:01 PM, Stephen wrote:
On Sat, Jul 11, 2020 at 09:05 AM, Tom Miller wrote:

Ok, that sounds like the main problem. That HV multiplier is also used
in the 475 scope as well as the A and B versions. You might check with Q
service in Greece ( excellent to deal with) or search the part number
152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but
a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton
multiplier. Should be some info in the archives on groups.io. It is a
tripler so three caps and three diodes plus a 1-3 meg carbon comp
resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards
Hmmm... Does it have to be a carbon comp resistor?
I may try to build one using the existing enclosure. I hope it’s not dipped in epoxy.
Dinos at Q-Service is out of this part.
He’s really a very nice guy. I’ve dealt with him a few time, and talked to him on the phone last week.

Maybe I can just replace the parts inside. But I have the feeling it’s not gonna be that easy...
Plus, replacing that part apparently requires removing the entire board, which is a project in itself.
Grrrr...

PS: Were those cracklings sounds i heard to be expected? That startled me. I hope nothing was damaged...

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Re: My first scope, a Tektronix 11401 with option 2D extended memory and two 11A34 plugins and an 11A33 plugin.

Jim Ford
 

114XX I have no interest in, but 118XX I do.  Having used a CSA803 at work (as well as an HP 54120) several decades ago, I would love to have a 118XX in my garage lab.  Tek beats HP with the modularity, and the Tek SD-24 sampling plug-in got "Best in Show", so to speak, from Jim Andrews of Picosecond Pulse Labs (acquired by Tek/Danaher in 2014).My $0.02.Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Precaud <jbau@...> Date: 7/11/20 5:53 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] My first scope, a Tektronix 11401 with option 2D extended memory and two 11A34 plugins and an 11A33 plugin. It takes a brave person to admit to liking and using an 11k-series scope  :)I have a couple and "like" them in remote-controlled applications, but hands-on operation is a different matter. The digitizer is excellent (if you need 10 bits), I love the large display, and the 11k preamps are superb. I think the entire user interface was designed with remote programming in mind. Even after years of occasional use I can't remember how to do some basic, simple stuff from the front panel. Because of this, it has earned a spot on the floor next to the bench, deployed only when needed.


Re: FG 504 function generator odd behaviour

Dave Daniel
 

Ir you end up having to replace any of the TO-3 pass transistors in the chassis, be aware that many (all?) new ones may have a different pinout than the originals.

Just something to be aware of.

DaveD

On Jul 11, 2020, at 17:22, Andy Warner <andyw@...> wrote:

On the FG504, the -25V rail is referenced off the +25V one.
Check for bad tantalums on the -25V rail and also independently check the
pass transistor used by that rail, it is in the chassis, not the module.

I have to work on the sweep section of my FG504, which looks like it will
be a right pain. Anyone got any tips for working on the middle board in
this unit ?

On Sat, Jul 11, 2020 at 13:09 Harvey White <madyn@...> wrote:

Generic steps:

turn scope off, wait 5 minutes or so, turn scope on. See if -25 is good
(something could have latched up).

with power off, check continuity of fuses or with power on, check for
very low voltage drop across the fuse. There must always be a voltage
drop because the fuse acts like a resistor.

Look at the bulk supply for the -25. Check against voltage readings on
the schematic. Go through regulator circuit to output and see what
doesn't match. Any transistor where the base-emitter voltage is the
wrong polarity indicates transistor is off. Any transistor (except a
darlington) where the B-E voltage exceeds 0.7 volts is likely bad.

Typical things to fail: pass transistor.

in the event of a short circuit, check the current sense resistor (the
low value one from the pass transistor to the output) and then check the
(frequently done like this) transistor which has the base/emitter
junction connected across the resistor. Too much current and the
transistor turns on, stealing base drive from the pass transistor, and
turning it off. Current limiting.

In many tek supplies, the - supply is a positive supply in topology,
with what would be the ground being the negative lead, and what you'd
think ought to be the positive output grounded. The voltage across the
pass transistor is the difference between the bulk supply and the
desired voltage.

Check also to see what the reference voltage is for the -25 volt
supply. It must be exact, otherwise the supply will be off.

Harvey


On 7/11/2020 1:56 PM, Colin Herbert via groups.io wrote:
Oops! I have checked the voltages and while the +25V (+24.99), +15V
(+14.98)
and -15V (-14.98) are just about bang on, the -25V is sitting at -3.58V.
I
really can't remember if this was the case when I checked previously,
but it
is now. I did manage to short something out with the DMM probes, so that
may
have given this problem, but sure as sure it needs to be fixed, but how?
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave
Daniel
Sent: 10 July 2020 18:13
To: TekScopes@groups.io
Subject: Re: [TekScopes] FG 504 function generator odd behaviour

The first thing to do is measure the power rails to make sure that the
voltages are in spec and clean.

DaveD

On Jul 10, 2020, at 13:04, Colin Herbert via groups.io
<colingherbert@...> wrote:
I have an FG 504 which is showing some odd behaviour. The triangle-wave
shows asymmetry in that the negative peaks of the wave are rounded-off at
any frequency and the positive ones have a similar but lesser problem at
higher frequencies. This also seems to manifest itself as what looks like
cut-off on the negative peaks of the sine-wave and lesser cut-off on
positive peaks. While the triangle-waves are more-or-less symmetrical,
the
sine-waves are definitely not so, showing a nearly three-to-one voltage
ratio in favour of positive peaks. There is also noticeably overshoot on
the
square-waves at anything above 1kHz and only a DC offset at frequencies
below 80Hz.
I am totally ignorant of how this function generator produces
triangle-waves, but I do understand that the square-waves and sine-waves
are
derived from the triangle-wave. Does anyone have any help that they can
offer? I would be grateful to get this useful function-generator working
properly.
Colin.









--
Andy



Re: Tektronix 2230

satbeginner
 

Hi,

That's why I suggested to look in old equipment as well

Sometimes it's inside an old laptop PS you can crack open, or behind the screen of a broken tablet.

It's a very small transformer, so only little is needed.


Re: Tektronix 2230

Jim Ford
 

Be aware it's not cheap; I remember paying about $30 for a roll.   I use it sparingly.  It drives me nuts when people at work use it to wrap packages and such!Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Raymond Cote <bluegrassdakine@...> Date: 7/11/20 2:02 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] Tektronix 2230 Digikey lists it as available in tape form. YMMV In matters of style, float with the current. In matters of Principle, stand like a rock. “.   —  Thomas Jefferson —> On Jul 11, 2020, at 02:54, Saroj Pradhan <sarojman.Pradhan@...> wrote:> > > >> On Sat, Jul 11, 2020, 1:04 PM satbeginner <castellcorunas@...> wrote:>> >> Hello Saroj,>> >> Many moons ago in the lab I worked we had a guy who made all the special>> use transformers we needed.>> >> I learned from him to use what he used :-)>> >> In between windings he used a thin layer of Kaptan foil (polyimide,  thin>> light brown, slightly transparent) held in place with a simple piece of>> normal electrical tape.>> Then the next winding, insulation layer, next winding, etc.>> >> This kaptan is heat resistant, thin and also provide s good isolation.>> >> Sometimes you find it as a foil used in old electrical devices,and you>> only need a little.>> >> Good luck,>> >> Leo>> >> >> >> > > >


Tektronix TM500/TM5000 extender version 1.0

Ke-Fong Lin
 

Hi everyone,

I've a small TM500/TM5000 extender project and it is basically completed.
It's been tested working as an extender.
It's been also tested working as a standalone debugging device. That is to power a plug-in from lab supplies, which can be useful for repair.
Everything is now on github:

https://github.com/anotherlin/tek_tm_ext

Can you guys have a look and tell me if you can make any sense of it?
It's basically the same as version 0.8, without the bodge wire needed:
https://groups.io/g/TekScopes/album?id=243643

I'll add some photos for reference on the github tomorrow, otherwise it may be a bit abstract.

The standalone AC supplies have not been tested, but I'm pretty confident. It's basically some wiring.
The power good (TM5000 PWR pin) circuitry neither because both my SG5010 and AA5001 ignore it
But it's also very simple, so it should work.

Best regards,


Re: Tektronix Blue paint

Richard Knoppow
 

Its better. The example I used in my post does not really have columns. I found that part of the preservation of formatting depends on the choice of font. If you use variable spacing and the reader uses fixed spacing things will not line up. I don't know a real cure for this.
   I suppose someone who mixes custom paints probably understands the formula.

On 7/11/2020 2:06 PM, Reed Dickinson wrote:
I am re-sending the data as the columns did not line up.    Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B  4Y22  Black,    C 33 Yellow oxide,  D 1Y29 Green,  W 1Y32 White, E 1Y45 Blue, Base 7-916Y = ounces, 4Y = 4 ounces,  48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin
Lamp Black  37 shots,  Thalo Green  22 half shots,  Thalo Blue 30 half shots, white 1 ounce 8 shots
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson, 1705 Stonehenge Drive, Tustin, CA  92780, reed714@...




--
Richard Knoppow
dickburk@...
WB6KBL


Re: FG 504 function generator odd behaviour

Andy Warner
 

On the FG504, the -25V rail is referenced off the +25V one.
Check for bad tantalums on the -25V rail and also independently check the
pass transistor used by that rail, it is in the chassis, not the module.

I have to work on the sweep section of my FG504, which looks like it will
be a right pain. Anyone got any tips for working on the middle board in
this unit ?

On Sat, Jul 11, 2020 at 13:09 Harvey White <madyn@...> wrote:

Generic steps:

turn scope off, wait 5 minutes or so, turn scope on. See if -25 is good
(something could have latched up).

with power off, check continuity of fuses or with power on, check for
very low voltage drop across the fuse. There must always be a voltage
drop because the fuse acts like a resistor.

Look at the bulk supply for the -25. Check against voltage readings on
the schematic. Go through regulator circuit to output and see what
doesn't match. Any transistor where the base-emitter voltage is the
wrong polarity indicates transistor is off. Any transistor (except a
darlington) where the B-E voltage exceeds 0.7 volts is likely bad.

Typical things to fail: pass transistor.

in the event of a short circuit, check the current sense resistor (the
low value one from the pass transistor to the output) and then check the
(frequently done like this) transistor which has the base/emitter
junction connected across the resistor. Too much current and the
transistor turns on, stealing base drive from the pass transistor, and
turning it off. Current limiting.

In many tek supplies, the - supply is a positive supply in topology,
with what would be the ground being the negative lead, and what you'd
think ought to be the positive output grounded. The voltage across the
pass transistor is the difference between the bulk supply and the
desired voltage.

Check also to see what the reference voltage is for the -25 volt
supply. It must be exact, otherwise the supply will be off.

Harvey


On 7/11/2020 1:56 PM, Colin Herbert via groups.io wrote:
Oops! I have checked the voltages and while the +25V (+24.99), +15V
(+14.98)
and -15V (-14.98) are just about bang on, the -25V is sitting at -3.58V.
I
really can't remember if this was the case when I checked previously,
but it
is now. I did manage to short something out with the DMM probes, so that
may
have given this problem, but sure as sure it needs to be fixed, but how?
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave
Daniel
Sent: 10 July 2020 18:13
To: TekScopes@groups.io
Subject: Re: [TekScopes] FG 504 function generator odd behaviour

The first thing to do is measure the power rails to make sure that the
voltages are in spec and clean.

DaveD

On Jul 10, 2020, at 13:04, Colin Herbert via groups.io
<colingherbert@...> wrote:
I have an FG 504 which is showing some odd behaviour. The triangle-wave
shows asymmetry in that the negative peaks of the wave are rounded-off at
any frequency and the positive ones have a similar but lesser problem at
higher frequencies. This also seems to manifest itself as what looks like
cut-off on the negative peaks of the sine-wave and lesser cut-off on
positive peaks. While the triangle-waves are more-or-less symmetrical,
the
sine-waves are definitely not so, showing a nearly three-to-one voltage
ratio in favour of positive peaks. There is also noticeably overshoot on
the
square-waves at anything above 1kHz and only a DC offset at frequencies
below 80Hz.
I am totally ignorant of how this function generator produces
triangle-waves, but I do understand that the square-waves and sine-waves
are
derived from the triangle-wave. Does anyone have any help that they can
offer? I would be grateful to get this useful function-generator working
properly.
Colin.









--
Andy


Re: Tektronix Blue paint

Richard Knoppow
 

The formatting is lost on my machine. perhaps you can send it they way I send photographic formulas. Example below.

Kodak D-76
Water (at 125F or 52C).................750.0 mL
Metol....................................2.0 grams
Sodium Sulfite, desiccated.............100.0 grams
Hydroquinon..............................5.0 grams
Borax, granular..........................2.0 grams
Water to make............................1.0 Liter

I think this will stay pretty much intact.

On 7/11/2020 1:44 PM, Reed Dickinson wrote:
Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B        4Y22        BlackC        33            Yellow oxideD        1Y29        GreenW        1Y32        WhiteE         1Y45        Blue
Y = ounces4Y = 4 ounces48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  Shots        Half shots
Lamp Black                37Thalo Green                22            1Thalo Blue                   30            1White             1 Oz      8
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson1705 Stonehenge DriveTustin, CA  92780reed714@...
--
Richard Knoppow
dickburk@...
WB6KBL


Re: Tektronix Blue paint

Reed Dickinson
 

I am re-sending the data as the columns did not line up.    Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B  4Y22  Black,    C 33 Yellow oxide,  D 1Y29 Green,  W 1Y32 White, E 1Y45 Blue, Base 7-916Y = ounces, 4Y = 4 ounces,  48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  
Lamp Black  37 shots,  Thalo Green  22 half shots,  Thalo Blue 30 half shots, white 1 ounce 8 shots                  
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson, 1705 Stonehenge Drive, Tustin, CA  92780, reed714@...


Re: Tek 465 Turns on, No Dot, No Trace

Stephen
 

On Sat, Jul 11, 2020 at 09:05 AM, Tom Miller wrote:


Ok, that sounds like the main problem. That HV multiplier is also used
in the 475 scope as well as the A and B versions. You might check with Q
service in Greece ( excellent to deal with) or search the part number
152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but
a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton
multiplier. Should be some info in the archives on groups.io. It is a
tripler so three caps and three diodes plus a 1-3 meg carbon comp
resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards

Hmmm... Does it have to be a carbon comp resistor?
I may try to build one using the existing enclosure. I hope it’s not dipped in epoxy.
Dinos at Q-Service is out of this part.
He’s really a very nice guy. I’ve dealt with him a few time, and talked to him on the phone last week.

Maybe I can just replace the parts inside. But I have the feeling it’s not gonna be that easy...
Plus, replacing that part apparently requires removing the entire board, which is a project in itself.
Grrrr...

PS: Were those cracklings sounds i heard to be expected? That startled me. I hope nothing was damaged...


Tektronix Blue paint

Reed Dickinson
 

Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B        4Y22        BlackC        33            Yellow oxideD        1Y29        GreenW        1Y32        WhiteE         1Y45        Blue
Y = ounces4Y = 4 ounces48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  Shots        Half shots
Lamp Black                37Thalo Green                22            1Thalo Blue                   30            1White             1 Oz      8      
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson1705 Stonehenge DriveTustin, CA  92780reed714@...


Re: Tek 465 Turns on, No Dot, No Trace

 

Ok, that sounds like the main problem. That HV multiplier is also used in the 475 scope as well as the A and B versions. You might check with Q service in Greece ( excellent to deal with) or search the part number 152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton multiplier. Should be some info in the archives on groups.io. It is a tripler so three caps and three diodes plus a 1-3 meg carbon comp resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards

On 7/11/2020 2:24 PM, Stephen wrote:
On Sat, Jul 11, 2020 at 06:24 AM, Tom Miller wrote:

There is a wire jumper at board location A-5 that provides the ground to
the HV multiplier. (note that I am going from old memory so take with a
grain of salt). Measure to ground to see if it is grounded. It is next
to a mounting screw for the multi module. Just lift one end and see if
the HV osc comes up.

If the HV osc is not running, all the CRT vltage readings will be off.

Regards
Ok, so I did lift that jumper. GOOD MEMORY BTW!!! A-5 it was!! Remind me NOT to ever play Naval BattleS with you!

The CRT came to life. I had something when playing With the Intensity and pushing the Beam Finder. But at the same time I did this, I heard some weird cracklings noises coming from the HV area, and a funny smell. Nothing caught fire though. I turn everything down and released the B Finder. Then I turned it off.
What say you? Is this good or bad? What are my options?

Best Regards

--
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Re: Cleaning TM500 module pushbutton switches

Roy Thistle
 

On Sat, Jul 11, 2020 at 08:20 AM, J Mcvein wrote:


it changed to petroleum
according to the filings, they are using hydro-treated spent lubricating oil.
fish oil is more valuable for making axle grease... a.k.a. as margarine.
Ya... don't use margarine to lube your TM500 module push-button switches.


Re: Cleaning TM500 module pushbutton switches

Roy Thistle
 

On Fri, Jul 10, 2020 at 06:18 PM, Greg Muir wrote:


wondering if WD40 Company has changed the formulation
The liquid stuff, in the gallon cans, in CONUS, is "different", from the spray, in a way that may explain your observations.
Too much chemistry, in one's posts, makes one unpopular...
But... "petroleum oils" oxidize, change colour, and become more viscous, in humid, and acidic (Hawaiian ocean air?) environments over sufficient time.
The spray imparts only a thin layer of "petroleum oil" ... and most of that drips off, along with the solvent. The little that remains... well...sunlight, heat, dust, and even microbes, they soon diminish that.
The oxidation of the thicker layer of "petroleum oil" applied... by using {heavy coatings} of the the liquid stuff, in the gallon cans could... at least partly explain what you observed.
Ya... don't use the liquid stuff, in the gallon cans, to dip your TM500 module push-button switches.

24881 - 24900 of 193905