Rotary wafer switch cleaner?

  • Thread starter The other John Smith
  • Start date
T

The other John Smith

Guest
Hi -

I have some old HP equipment with rotary wafer switches with contacts which
appear to be silver plated. They have become noisy. I have seen contact
cleaners but I worry that they may cause other problems. I would very much
appreciate hearing how others handle this problem, be it contact cleaners or
some other method.

Your comments will be greatly appreciated.

John
 
The other John Smith wrote:
Hi -

I have some old HP equipment with rotary wafer switches with contacts which
appear to be silver plated. They have become noisy. I have seen contact
cleaners but I worry that they may cause other problems. I would very much
appreciate hearing how others handle this problem, be it contact cleaners or
some other method.

Your comments will be greatly appreciated.

John
Click to expand...
Any electronic contact cleaner will help.
Ages ago, General Cement (or a company with name similar to
"chemco"??) made "De-Oxide" in two forms (prolly had different trade
names): concentrated (dark orange or reddish, transparent), and
"standard" or normal dilution (pale orange, transparent).
This stuff was made eXpressly for silver contacts; would remove
oxides, sulfides, and other junk off the contacts, and add a thin
protective film of some kind of oil.
You would not believe how good the De-Oxide was on very crappy totally
nonconductive silver contacts (in TV tuners).
Used the standard version for all normalcontact cleaning, and De-Oxide
for nasties.
The better contact cleaners now have silicone as the protecting "oil"
or agent.
There may still be a "contact cleaner" that is sh*t and should be
avoided at all costs, but i do not know what brand that was/now-is;
think it is in a spray can.
I think "blue ice" may be the name of one rather nasty crap; avoid
anything that sounds like it "repairs" - especially if the blurbs imply
that the crap is conductive.
That junk slowly spreads ("crawls" is a term that some use), creating
conductive paths that should never exist.
I hear it is hard to remove.
 
"Robert Baer" <robertbaer@earthlink.net> wrote in message
news:411B388A.C045CAB0@earthlink.net...
The other John Smith wrote:

Hi -

I have some old HP equipment with rotary wafer switches with contacts
which
appear to be silver plated. They have become noisy. I have seen contact
cleaners but I worry that they may cause other problems. I would very
much
appreciate hearing how others handle this problem, be it contact
cleaners or
some other method.

Your comments will be greatly appreciated.

John

Any electronic contact cleaner will help.
Ages ago, General Cement (or a company with name similar to
"chemco"??) made "De-Oxide" in two forms (prolly had different trade
names): concentrated (dark orange or reddish, transparent), and
"standard" or normal dilution (pale orange, transparent).
This stuff was made eXpressly for silver contacts; would remove
oxides, sulfides, and other junk off the contacts, and add a thin
protective film of some kind of oil.
You would not believe how good the De-Oxide was on very crappy totally
nonconductive silver contacts (in TV tuners).
Used the standard version for all normalcontact cleaning, and De-Oxide
for nasties.
The better contact cleaners now have silicone as the protecting "oil"
or agent.
There may still be a "contact cleaner" that is sh*t and should be
avoided at all costs, but i do not know what brand that was/now-is;
think it is in a spray can.
I think "blue ice" may be the name of one rather nasty crap; avoid
anything that sounds like it "repairs" - especially if the blurbs imply
that the crap is conductive.
That junk slowly spreads ("crawls" is a term that some use), creating
conductive paths that should never exist.
I hear it is hard to remove.
Click to expand...

Thanks for the heads-up, Robert. I'll try to avoid those products.

John
 
"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns95446C90ABE6Djyanikkuanet@204.117.192.21...
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net:

Hi -

I have some old HP equipment with rotary wafer switches with contacts
which appear to be silver plated. They have become noisy. I have seen
contact cleaners but I worry that they may cause other problems. I
would very much appreciate hearing how others handle this problem, be
it contact cleaners or some other method.

Your comments will be greatly appreciated.

John



I used to use Tarn-X to clean silver-plated switches in TEK tube-type
o'scopes.You have to rinse well,then dry in an oven for 3 days to remove
the moisture.Then a tuner cleaner/lube spray would help protect the bright
silver.

--
Jim Yanik
jyanik-at-kua.net
Click to expand...
Hi, Jim -

It creates a bit of a problem for me to put a rack-mount instrument into an
oven. However, I think your tip is a good one and I'll remember it for use
on other items. Thanks.

John
 
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net:

Hi -

I have some old HP equipment with rotary wafer switches with contacts
which appear to be silver plated. They have become noisy. I have seen
contact cleaners but I worry that they may cause other problems. I
would very much appreciate hearing how others handle this problem, be
it contact cleaners or some other method.

Your comments will be greatly appreciated.

John
Click to expand...
I used to use Tarn-X to clean silver-plated switches in TEK tube-type
o'scopes.You have to rinse well,then dry in an oven for 3 days to remove
the moisture.Then a tuner cleaner/lube spray would help protect the bright
silver.

--
Jim Yanik
jyanik-at-kua.net
 
"The other John Smith" <jocjo-john@yooha.com> wrote in message
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net...
Hi -

I have some old HP equipment with rotary wafer switches with contacts
which
appear to be silver plated. They have become noisy. I have seen contact
cleaners but I worry that they may cause other problems. I would very much
appreciate hearing how others handle this problem, be it contact cleaners
or
some other method.
Click to expand...

Last month I fixed up an old HP 654A test oscillator whose attenuator was
flaky due to bad contacts on the rotary wafer switch. I was not able to get
full perfection, but I did get very substantial improvement. (Contacts that
had been entirely open-circuit went to between 40 and 500 mohms, but still a
little flaky if you wiggle the knob.)

I used Caig Labs "Deoxit", the aerosol in the red can. (I think Caig Labs
is the same company that used to be called, or make, "Cramolin.") It took
about four or five cycles of spray, wait a few seconds, rotate and wiggle
knob, repeat. I put paper towels around the switch to control overspray;
but the material itself is *not* conductive or corrosive.

In general I have had good results with Caig Labs products, and I have never
found them to cause any damage when used this way.
 
In the specific case of Tektronix scopes, I never believed in contact
cleaners. In my personal experience (and yours may be different) the noisy
switch issues are generally caused by dust and dirt, not tarnish and wear. I
generally flood the contacts with isopropyl alcohol or some other solvent
(Freon, in days of old) that dries completely. Then I put the smallest
possible amount or Cramolin or some such, the amount that a toothpick will
hold, directly on the rotating contact. This solves the problem of
oil-soaked wafers which you so often see when contact cleaner has been used.
A tiny drop of oil where the shaft passes through the bushing does wonders,
too.

I always cringe when I open up a piece of equipment and see the oil spots
full of dirt where contact cleaner has been generously used.

Your mileage may of course vary.




"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns9544B3F5DC46Djyanikkuanet@204.117.192.21...
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:wT5Tc.21076$cK.7178@newsread2.news.pas.earthlink.net:


"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns95446C90ABE6Djyanikkuanet@204.117.192.21...
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net:

Hi -

I have some old HP equipment with rotary wafer switches with
contacts which appear to be silver plated. They have become noisy.
I have seen contact cleaners but I worry that they may cause other
problems. I would very much appreciate hearing how others handle
this problem, be it contact cleaners or some other method.

Your comments will be greatly appreciated.

John



I used to use Tarn-X to clean silver-plated switches in TEK tube-type
o'scopes.You have to rinse well,then dry in an oven for 3 days to
remove the moisture.Then a tuner cleaner/lube spray would help
protect the bright silver.

--
Jim Yanik
jyanik-at-kua.net

Hi, Jim -

It creates a bit of a problem for me to put a rack-mount instrument
into an oven. However, I think your tip is a good one and I'll
remember it for use on other items. Thanks.

John




Well,at the two TEK service centers I worked at,we had drying ovens just
for that.Those 500 series TEK tube scopes were pretty big.

You could make a temporary drying box and use a bank of 100W lamps to heat
it,and a few muffin fans for the 'exhaust',that gives you a negative
pressure inside to draw out moisture.

Like a big "Easy-Bake" oven. ;-)

--
Jim Yanik
jyanik-at-kua.net
Click to expand...
 
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:wT5Tc.21076$cK.7178@newsread2.news.pas.earthlink.net:

"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns95446C90ABE6Djyanikkuanet@204.117.192.21...
"The other John Smith" <jocjo-john@yooha.com> wrote in
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net:

Hi -

I have some old HP equipment with rotary wafer switches with
contacts which appear to be silver plated. They have become noisy.
I have seen contact cleaners but I worry that they may cause other
problems. I would very much appreciate hearing how others handle
this problem, be it contact cleaners or some other method.

Your comments will be greatly appreciated.

John



I used to use Tarn-X to clean silver-plated switches in TEK tube-type
o'scopes.You have to rinse well,then dry in an oven for 3 days to
remove the moisture.Then a tuner cleaner/lube spray would help
protect the bright silver.

--
Jim Yanik
jyanik-at-kua.net

Hi, Jim -

It creates a bit of a problem for me to put a rack-mount instrument
into an oven. However, I think your tip is a good one and I'll
remember it for use on other items. Thanks.

John
Click to expand...
Well,at the two TEK service centers I worked at,we had drying ovens just
for that.Those 500 series TEK tube scopes were pretty big.

You could make a temporary drying box and use a bank of 100W lamps to heat
it,and a few muffin fans for the 'exhaust',that gives you a negative
pressure inside to draw out moisture.

Like a big "Easy-Bake" oven. ;-)

--
Jim Yanik
jyanik-at-kua.net
 
"BFoelsch" <BFoelsch@comcast.ditch.this.net> wrote in message
news:3oidnXAjtqdpqoDcRVn-qA@giganews.com...
In the specific case of Tektronix scopes, I never believed in contact
cleaners. In my personal experience (and yours may be different) the noisy
switch issues are generally caused by dust and dirt, not tarnish and wear.
I
generally flood the contacts with isopropyl alcohol or some other solvent
(Freon, in days of old) that dries completely. Then I put the smallest
possible amount or Cramolin or some such, the amount that a toothpick will
hold, directly on the rotating contact. This solves the problem of
oil-soaked wafers which you so often see when contact cleaner has been
used.
A tiny drop of oil where the shaft passes through the bushing does
wonders,
too.

I always cringe when I open up a piece of equipment and see the oil spots
full of dirt where contact cleaner has been generously used.
Click to expand...

I know what you mean. Thanks for the hints.

John
 
"Walter Harley" <walterh@cafewalterNOSPAM.com> wrote in message
news:cfitpf$96l$0$216.39.172.65@theriver.com...
"The other John Smith" <jocjo-john@yooha.com> wrote in message
news:SrXSc.19456$9Y6.11891@newsread1.news.pas.earthlink.net...
Hi -

I have some old HP equipment with rotary wafer switches with contacts
which
appear to be silver plated. They have become noisy. I have seen contact
cleaners but I worry that they may cause other problems. I would very
much
appreciate hearing how others handle this problem, be it contact
cleaners
or
some other method.


Last month I fixed up an old HP 654A test oscillator whose attenuator was
flaky due to bad contacts on the rotary wafer switch. I was not able to
get
full perfection, but I did get very substantial improvement. (Contacts
that
had been entirely open-circuit went to between 40 and 500 mohms, but still
a
little flaky if you wiggle the knob.)

I used Caig Labs "Deoxit", the aerosol in the red can. (I think Caig Labs
is the same company that used to be called, or make, "Cramolin.") It took
about four or five cycles of spray, wait a few seconds, rotate and wiggle
knob, repeat. I put paper towels around the switch to control overspray;
but the material itself is *not* conductive or corrosive.

In general I have had good results with Caig Labs products, and I have
never
found them to cause any damage when used this way.
Click to expand...

I'll look up the Cramolin and Deoxit and see about getting some. Thanks for
the input.

John
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top