What du use cleaning the Volts/div switches on a Tekronix 2225?

[ErikTheNorwegian]

What do i use cleaning the Volts/div switches on a Tekronix 2225 ?

After Dave's rave about the 2225, i bought one cheap on the bay, but the volts/div is in bad need of a cleaning.
So what do i use so i don't get  dry contacts, or do more damage?

I was thinking of pressurised air and some clean alcohol..

Do anyone have  a advice ?

[sonicj]

i don't have a 2225, but i normally clean switches and pots with 91% isopropyl alcohol. kimwipes are great for this sort of task as well as medical cotton swabs. if i can't break the part down completely, i'll use compressed air .

for removing oxidation, i use a fiberglass pen or something like 1000 grit sand paper.

NO-OX-ID is my preferred contact grease, but if i can't get to the contacts i hose it down with PreservIT from Caig Labs.
-sj

[Kiriakos-GR]

There is lots of fiberglass pens out there, but the point is to get the correct grid.

Some people use them for modeling  like to brush the wheels of small scale trains.

But the point is that we do not need shine, we need something hard enough to remove the remains of sparks and flames.
I found the listings about the fiberglass pens grids very confusing.
If i could touch those fiberglass refill's I could tell what I need, but there is no chance to find them in the local market.   

[hacklordsniper]

Sanding is bad option since its will remove thin contact plating

[DonRon]

In Germany you can get "Ballistol"-oil. It is the "magic fluid", which can be used for nearly everything :-).

Lot of people use it to clean electric contacts - mainly it is known and used as an oil to clean weapons.
I used it to clean the switches in my > 40 years old Drake R4B-Receiver and also in an Yaesu FT101-Transceiver.
Works great and prevents further oxidation for some time. Also if you clean with alcohol you should additionally treat the contacts with somethings which prevents further oxidation.
Maybe you can get Ballistol in Norway.

 http://www.ballistol.de/index.php?article_id=90&clang=0

I prefer the 50 ml (Art Nr 21000) - costs about 2.50 Euro's - u can buy it in every pharmacy in Germany.

Greet's
Ronald

[BravoV]

For a really-really old mechanical switch or electrical contact, usually I will be a bit careful on using chemical on them, cause there is a possibility that the material will not react nicely to the chemical used that is made now. Not very sure though.

If it is possible to disassemble the switch, I know this sounds weird, usually I used a plain pencil rubber eraser to rub and clean out the contact points, especially they've been used in a really humid and dusty place, those gunks or dirts might affect them between the two contact points even they're gold plated.

The problem is not chemical since they can't corrode the gold, instead the reason is because its mechanical problem, like a very thin film layer of dirt or sort of fat developed caused by constantly grinding between the two contacts, and formed or sand witched between them.

This eraser trick worked very well, learned this from an antique radio collector freak.

[hacklordsniper]

In Germany you can get "Ballistol"-oil. It is the "magic fluid", which can be used for nearly everything :-).

In my lab it is essential to have i and i must admit this is one of most magical and clever things ever invented by Germans. I like to say only use that is not possible is to spread it on sliced bread for breakfast

As for BravoV sugestion i can confirm mechanical pencil eraser is a wonderful thing on brass and copper.

[david77]

...is not possible is to spread it on sliced bread for breakfast

As far as I know you could as it is non toxic, wouldn't taste very nice, though .

And yes it is the pen knife in a can, I also always have one around.

If I need something a bit more aggressive I use CRC Industries K60 and the WL spray on a "leather cleaning stick" (I don't know the english name for that, used to be used to clean video heads and such). And after the cleaning a dab of Ballistol to protect the contacts.
This way I've cleaned the switches in a Philips scope and the HP 400 voltmeter and many more things.

[Richard W.]

The cleaning-effect is caused by the Oleic acid in Ballistol. The pH-Value is about 8,5
So, in my opinion it's okay for cleaning, but not for conservation.

[DonRon]

That's right Richard. The cleaning effect is due to the basic character.
But the basic character ist very weak and during cleaning it gets neutralized if you use only a small portion of ballistol.
It is important - as always while using chemicals - to use only as much as necessary.

I know from several ham radio operators that they use it without any problems. Clean contacts in old ham radio equipment, also lubricating the mechanical parts.
But maybe it is better to use something different for a long time conservation. Do you have any suggestion for that Richard?
(Will work on a very old Drake R2 receiver the next days - have to clean the contacts of the band switch too. So would be good to knew what to use for "perfect" conservation).

[hacklordsniper]

As far as I know you could as it is non toxic, wouldn't taste very nice, though .

Well originally it was designed to be used on wounds too if i remember correctly from brochure...

[flolic]

Kontakt-Chemie Kontakt60/61 is what I use for cleaning all sorts of switches, connectors and potentiometers...

[ErikTheNorwegian]

I thank everybody for many good advises!   

I`l try Kontakt-Chemie Kontakt60/61, as its a purpose chemical, made for contacts. I`m afraid of no purpose means, my  experience is that chemicals on contacts often is a short therm problem solver.

Acid solutions/ high Ph, can get into to the circuit board itself and corrode the layers etc.

You can clearly see the switches in Dave's video, on the mainboard..

I`l keep You updated.. :-)

I have a Tektronix 2430A that came to me without power supplay that i cooping now, so if there is anyone that need parts.. just PM..

[Richard W.]

Here is the exact description of how to use these products: (second page, lower third)
http://www.crcind.com/wwwcrc/tds/TKC3%20KONTAKT60/css/TKC3%20KONTAKT60.htm

All these tinctures should work fine, but be carefull they're flammable.
So maybe not the best option for high current and high voltage applications?!

Also for voltages below 1V KONTAKT 61 is not recommended. (see paragraph 4. Directions)
http://www.crcind.com/wwwcrc/tds/TKC3%20KONTAKT61.PDF

Obviously it's rocket science 

I clean all contacts with isopropanol and cotton swabs or paper.
The best protection from corroded contacts is using them and a dry room for storage

[alm]

But the point is that we do not need shine, we need something hard enough to remove the remains of sparks and flames.

What do you do with your scopes that causes sparks and flames in the vertical attenuator?

Erik: You might want to search the TekScopes Yahoo! group archive how to clean cam switches, some solvents may be absorbed by the plastic. I believe the various Caig products (eg. DeOxit) are popular.

[Kiriakos-GR]

Actually I have in mind to clean the CPU socket of my computer, because the CPU acts funny at booting up.

And I need the heavy duty version of this fiberglass pens, if there is any !!

About scopes, it looks that my first one will be digital.   

[ErikTheNorwegian]

I do think that i will "soak"  the switches with a little alcohol, and the use some pressurised air and  dry it out. But all while the scope is upside down.. in other words clean them the the Aussie way! Just to prevent the fluid and dirt to go into the mainboard.

Pictures and my story how it goes will follow.. :-)

[FreeThinker]

In Germany you can get "Ballistol"-oil. It is the "magic fluid", which can be used for nearly everything :-).

Lot of people use it to clean electric contacts - mainly it is known and used as an oil to clean weapons.
I used it to clean the switches in my > 40 years old Drake R4B-Receiver and also in an Yaesu FT101-Transceiver.
Works great and prevents further oxidation for some time. Also if you clean with alcohol you should additionally treat the contacts with somethings which prevents further oxidation.
Maybe you can get Ballistol in Norway.

 http://www.ballistol.de/index.php?article_id=90&clang=0

I prefer the 50 ml (Art Nr 21000) - costs about 2.50 Euro's - u can buy it in every pharmacy in Germany.

Greet's
Ronald

You forgot to mention that it can also be used to kill ticks and mites (read the label) Lol. Strange but true (it has disinfectant property's). I used it for many years in the microfilm industry, much better than wd40 and solvent cleaners (low residue, non corrosive etc ) thoroughly recommended.

[ErikTheNorwegian]

In Germany you can get "Ballistol"-oil. It is the "magic fluid", which can be used for nearly everything :-).

Lot of people use it to clean electric contacts - mainly it is known and used as an oil to clean weapons.
I used it to clean the switches in my > 40 years old Drake R4B-Receiver and also in an Yaesu FT101-Transceiver.
Works great and prevents further oxidation for some time. Also if you clean with alcohol you should additionally treat the contacts with somethings which prevents further oxidation.
Maybe you can get Ballistol in Norway.

 http://www.ballistol.de/index.php?article_id=90&clang=0

I prefer the 50 ml (Art Nr 21000) - costs about 2.50 Euro's - u can buy it in every pharmacy in Germany.

Greet's
Ronald

You forgot to mention that it can also be used to kill ticks and mites (read the label) Lol. Strange but true (it has disinfectant property's). I used it for many years in the microfilm industry, much better than wd40 and solvent cleaners (low residue, non corrosive etc ) thoroughly recommended.

Well might be the solution to kill the bug in the scope... :-)

[Kiriakos-GR]

Well might be the solution to kill the bug in the scope... :-)

That's a good one... 

Even so my first fiberglass pen had be shipped, and I am expecting it in 5-6 days or so.   

[SgtRock]

Dear Erik:

--Have you ever tried DeoxIT D100L?

--I, as well, use the high purity isopropyl, with good results. Also, I have used CRC Electra-Motive Electric Parts Cleaner, followed by compressed air. It evaporates very quickly and is non-flammable, but be sure your area is well ventilated. If all else fails, you might consider trying DeoxIT D100L, if you can apply it without getting it on the wafers (especially those effing phenolic ones). I have had satisfactory results with it.

--Apply very sparingly, rotate the switch periodically over the course of an hour or two, then clean with isopropyl. Apply DeoxIT Gold, or DeoxIT Shield to preserve. If that does not do it you may have to try the pencil eraser trick. I have even used the striker from a book of matches, to slide between the contacts, as with the old automotive points. Someone on this forum said there is a special tool to do this, but I cannot find the post.

--I regularly use this stuff on recalcitrant USB and SATA cable jacks with good results. I also use it on my DMM probes' banana jacks whenever the parasitic resistance increases above 0.15 Ohms or so.

--Let me be very clear. The DeoxIT solution is only for "no go" and or intermittants do to dirt and grime, and light oxidation. It will not, needless to say, cure mechanical problems. I only mention this because, the last time I recommended this stuff, someone quoted me, and a person who has my posts set on ignore, rang in and accused me of recommending "magic goop". Then somebody accused me of waving a dead squirrel at the problem. So whatever you do, do not quote the first sentence of the post, unless you want a laugh.

--Once upon a time, I had a multiple wafer switch with a "no go" problem. I tried all of the above, but still no joy. So, after taking a lot of pictures and making notes. I removed the switch for closer inspection and, proceeded to check every set of contacts with a voltmeter (desoldering components as necessary). Finally, I found a contact on one of the wafers that had an almost invisible break in it. I managed to close the break with solder, and Bobs your uncle. Do not give up! There are already enough shelf queens about.

"But leave the Wise to wrangle, and with me
The Quarrel of the Universe let be:
And, in some corner of the Hubbub couch'd,
Make Game of that which makes as much of Thee.
"Omar Khyayyam" 1048 1131

 
Best Regards
Clear Ether