17 Feb
2002
17 Feb
'02
5:54 a.m.
Hello People,
I just set up a new shelf unit from InterMetro for my TV and my
audio/video system in my living room. My Amp is an old Onkyo from the
early 70's. I need to clean the switches and pots. I get reduced sound
output occasionally and I can usually fix it by wiggling a few of the
switches, so I'm thinking a good cleaning is in order. I tried once
before, but used an electrical cleaner, probably not meant for fine
electronic use. Also, I didn't remove the faceplate, so I didn't have
very good access.
What can I buy, hopefully at Radio Shack, that I can clean the switches
with? Also, is there some sort of lubricant I should spray into the
switches afterwards? I like my audio/video system as it's a mix of new
amd old, but I need it to sound good besides look cool!
Chad Fernandez
Michigan, USA
17 Feb
17 Feb
7:44 a.m.
IMHO, there is no substitute for simply disassembling
a pot, cleaning it, and then reforming (the "nice"
term for bending) the pot wiper to restore its spring.
Most of the time inexpensive pots were put together
with just bent tabs. I've brought 99% of bad pots on
audio stuff and music synthesizers back to 100% useful
life doing this. Laborious, but good if you can't
easily replace 'em.
--- Chad Fernandez <fernande(a)internet1.net> wrote:
Hello People,
I just set up a new shelf unit from InterMetro for
my TV and my
audio/video system in my living room. My Amp is an
old Onkyo from the
early 70's. I need to clean the switches and pots.
I get reduced sound
output occasionally and I can usually fix it by
__________________________________________________
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Yahoo! Sports - Coverage of the 2002 Olympic Games
http://sports.yahoo.com
8:39 a.m.
Loboyko Steve wrote:
IMHO, there is no substitute for simply disassembling
a pot, cleaning it, and then reforming (the "nice"
term for bending) the pot wiper to restore its spring.
Most of the time inexpensive pots were put together
with just bent tabs. I've brought 99% of bad pots on
audio stuff and music synthesizers back to 100% useful
life doing this. Laborious, but good if you can't
easily replace 'em.
Antique Electronics Supply sells some nice ( but pricey $175)
stepped Attenuators. You can get your tubes too if it is real
vintage audio. www.tubesandmore.com
--
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
1:21 p.m.
All my stuff is solid state, no tubes. I don't have anything that is
truly worth a lot, I don't think. I'd just like to have consistant
sound. Where's Tony, on this?
Chad Fernandez
Michigan, USA
Ben Franchuk wrote:
Antique Electronics Supply sells some nice ( but
pricey $175)
stepped Attenuators. You can get your tubes too if it is real
vintage audio. www.tubesandmore.com
--
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
4:14 p.m.
I've got an old McIntosh MA-5100 working as my phono preamp until I hack
something better, the volume pots always gummed up in my ancient and dusty
house, a can of compressed air usually does the trick for a month or so. For
a more permanent solution, try capping the pots with cut, black plastic film
cannisters. Works wonders for me.
----- Original Message -----
From: "Chad Fernandez" <fernande(a)internet1.net>
To: <classiccmp(a)classiccmp.org>
Sent: Sunday, February 17, 2002 10:21 PM
Subject: Re: OT: cleaning pots on my vintage audio amp
All my stuff is solid state, no tubes. I don't
have anything that is
truly worth a lot, I don't think. I'd just like to have consistant
sound. Where's Tony, on this?
Chad Fernandez
Michigan, USA
Ben Franchuk wrote:
Antique Electronics Supply sells some nice ( but
pricey $175)
stepped Attenuators. You can get your tubes too if it is real
vintage audio. www.tubesandmore.com
--
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
18 Feb
18 Feb
10:52 a.m.
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3 p.m.
Tony Duell wrote:
Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol. It's safe on just
about everything, so it's not going to make matters worse. And it
gernerally gets swtiches (at least) working again.
Ok, is that a chemical name, or a product name?
For pots you generally have to remove them from the unit and bend up the
tabs holding on the cover. If the resistance track is very badly worn,
then you should probably fit a new pot if it's a standard item.
Double-gang pots can be a little harder to dismandle, particularly the
rear section.
Wonderful.... I don't know if I can do that. Last time I tried cleaning
them, I couldn't figure out how to easily remove the faceplate. The
pots aren't very accessible. I guess I'll have to have another go at
it, However.
If the track is not too bad, then sometimes rubbing a soft pencil over it
will help. Don;'t overdo it, though. And increase the wiper tension a
little, but too much tension will lead to wear. If thw wiper is much
narrower than the track (and it often is on cheap pots), then sometimes
you can bend it sideways to contact a different part of the track.
But to be honest, for controls you'll use a lot (volume, etc) it's
probably best to replace the pot if it's at all standard.
How can I tell if they are standard? Who would be the best to order new
ones from? I've never purchased components like this before.
Chad Fernandez
Michigan, USA
3:34 p.m.
On Tue, 19 Feb 2002, Chad Fernandez wrote:
Tony Duell wrote:
Here in the states, several companies make control/pot cleaners. Some of
the most popular brands are:
Chemtronics [http://www.chemtronics.com/]
Rawn America [http://www.rawnamerica.com/]
Rite Off [http://www.riteoff.com/
Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol. It's safe on just
about everything, so it's not going to make matters worse. And it
gernerally gets swtiches (at least) working again.
Ok, is that a chemical name, or a product name? Wonderful.... I don't know if I can do that. Last
time I tried
cleaning them, I couldn't figure out how to easily remove the
faceplate. The pots aren't very accessible. I guess I'll have to
have another go at it, However.
How can I tell if they are standard? Who would be the
best to order
new ones from? I've never purchased components like this before.
I'd recommend trying to clean the pots with a *good* cleaner before even
considering taking them apart or replacing them. It is next to impossible
to find a proper replacement for many of the pots used in old audio gear,
and they are easily damaged.
-Toth
3:51 p.m.
On Mon, 18 Feb 2002, Tothwolf wrote:
On Tue, 19 Feb 2002, Chad Fernandez wrote:
Err, Rite Off [http://www.riteoffinc.com/]
-Toth
Tony Duell wrote:
Here in the states, several companies make control/pot cleaners. Some of
the most popular brands are:
Chemtronics [http://www.chemtronics.com/]
Rawn America [http://www.rawnamerica.com/]
Rite Off [http://www.riteoff.com/ Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol. It's safe on just
about everything, so it's not going to make matters worse. And it
gernerally gets swtiches (at least) working again.
Ok, is that a chemical name, or a product name? 
7:42 p.m.
Would those also also work with the old wire(spring ?)-wound pots. Those
on my old EICOs are pretty scratchy. One shop told me that WD-40 could
do wonders, but that didn't set right by me.
Lawrence
On Tue, 19 Feb 2002, Chad Fernandez wrote:
Reply to:
lgwalker(a)mts.net
Tony Duell wrote:
Here in the states, several companies make control/pot cleaners. Some of
the most popular brands are:
Chemtronics [http://www.chemtronics.com/]
Rawn America [http://www.rawnamerica.com/]
Rite Off [http://www.riteoff.com/
Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol. It's safe on just
about everything, so it's not going to make matters worse. And it gernerally
gets swtiches (at least) working again.
Ok, is that a chemical name, or a product name? Wonderful.... I don't know if I can do that.
Last time I tried
cleaning them, I couldn't figure out how to easily remove the
faceplate. The pots aren't very accessible. I guess I'll have to
have another go at it, However.
How can I tell if they are standard? Who would
be the best to order
new ones from? I've never purchased components like this before.
I'd recommend trying to clean the pots with a *good* cleaner before even
considering taking them apart or replacing them. It is next to impossible
to find a proper replacement for many of the pots used in old audio gear,
and they are easily damaged.
-Toth
19 Feb
19 Feb
4:51 a.m.
--- Chad Fernandez <fernande(a)internet1.net> wrote:
Tony Duell wrote:
It's labelled "isopropanol" in the States.
-ethan
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - Coverage of the 2002 Olympic Games
http://sports.yahoo.com
Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol.
Ok, is that a chemical name, or a product name? 
5:21 a.m.
On Tue, 19 Feb 2002, Ethan Dicks wrote:
It's labelled "isopropanol" in the States.
Isn't the IUPAC convention to prefix the carbon number? Like so:
2-propanol?
Peace... Sridhar
Right here... I've not got a lot to add....
I generally clean pots and swtiches with propan-2-ol.
Ok, is that a chemical name, or a product name? 
5:33 a.m.
I generally
clean pots and swtiches with propan-2-ol.
Ok, is that a chemical name, or a product
name?
7:28 a.m.
On Tue, 19 Feb 2002, Fred Cisin (XenoSoft) wrote:
Isn't the IUPAC convention to prefix the
carbon number? Like so:
2-propanol?
Or you can call it "Isopropyl alcohol" or just "rubbing alcohol"!
(But you want the 90+% stuff, NOT the 70%)
But I don't think either of those are official convention.
Peace... Sridhar
> I
generally clean pots and swtiches with propan-2-ol.
Ok, is that a chemical name, or a product name?
It's labelled
"isopropanol" in the States.
7:39 a.m.
> > I
generally clean pots and swtiches with propan-2-ol.
> Ok, is that a chemical name, or a product name?
It's labelled "isopropanol" in the States.
Isn't the IUPAC
convention to prefix the carbon number? Like so:
2-propanol?
11:19 a.m.
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3:30 p.m.
Too hard, better to have another lister translate :-)
Chad Fernandez
Michigan, USA
Tony Duell wrote:
Unfortunately the 'local' names are just that.
Local. I've never see
anything called 'rubbing alcohol' for sale in the UK. I have seen it
labelled isopropanol or propan-2-ol. Since this is an international list,
it would seem to make sense to use the official name and then to look it
up in a local chemical catalogue if necessary.
-tony
20 Feb
20 Feb
5:01 a.m.
Rumor has it that Tony Duell may have mentioned these words:
In spite of not being "official convention" (and sometimes not even
CORRECT), when telling somebody to get something, it just might be useful
to them to know what it is called at the places that they buy it.
Unfortunately the 'local' names are just that. Local. I've never see
anything called 'rubbing alcohol' for sale in the UK. I have seen it
labelled isopropanol or propan-2-ol. Since this is an international list,
it would seem to make sense to use the official name and then to look it
up in a local chemical catalogue if necessary.
Although I agree with you totally, for many things there is *no*
international name. If you send anyone over to Wal-mart or K-mart for
isopropanol or propan-2-ol, they'll *never* find it. I've only ever seen
labeled is "rubbing alcohol" (which I'll admit is much too vague) or
"isopropyl alcohol" and the percentage (you can get 91% at Wal-mart, but
most places stock only the 70% AFAIK. (I'm looking at a bottle as I type)
Even under the ingredient listing (required by law in the US) it's
"isopropyl alcohol".
But it could be fun to go into Radio Shack and ask... ;-)
Over here, cars have "trunks" instead of "boots", "hoods"
instead of
"bonnets", and I've even heard (but is unconfirmed) and there are some
things that are un-translatable, if you don't know the lingo beforehand...
Even "aluminum" is different, but I don't remember how different...
That's why it's helpful to know what it's called in various regions of the
world, or maybe someone could set up a database??? (I have access to a
ColdFusion server & PostgreSQL... :-)
That's Allz I know...
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.
Or you can
call it "Isopropyl alcohol" or just "rubbing alcohol"!
(But you want the 90+% stuff, NOT the 70%)
But I don't think either of those are official convention. 
6:18 a.m.
Hi,
Roger Merchberger <zmerch(a)30below.com> said:
Although I agree with you totally, for many things
there is *no*
international name. If you send anyone over to Wal-mart or K-mart for
isopropanol or propan-2-ol, they'll *never* find it. I've only ever seen
labeled is "rubbing alcohol" (which I'll admit is much too vague) or
"isopropyl alcohol" and the percentage (you can get 91% at Wal-mart, but
most places stock only the 70% AFAIK. (I'm looking at a bottle as I type)
Even under the ingredient listing (required by law in the US) it's
"isopropyl alcohol".
Here in the UK, I use "Servisol" IPA170 in an aerosol can with a nozzle
for getting ito difficult places - it's labelled Isopropyl Alcohol
(Conforms to BS 1595, ASTM D770 and DIN 53245, it says...)
Very useful stuff.
--
Cheers,
Stan Barr stanb(a)dial.pipex.com
The future was never like this!
19 Feb
19 Feb
6:33 a.m.
On Tue, 19 Feb 2002, Julius Sridhar wrote:
Isn't the IUPAC convention to prefix the carbon
number? Like so:
2-propanol?
It is convention to precede the part that is described by the number, by
the number. So propan-2-ol is correct, since it's the alcohol group
that's on the second carbon from the end. It would be ambiguous to
precede the whole thing with the numbers if there were two or more groups
attached to the carbon skeleton. Thus names like
1,2-dichloro-1-bromoprop-2-ene, for:
Cl Cl
| |
H - C - C = C - H
| |
Br H
Richard Schauer
3:16 p.m.
Rubbing alcohol, that isn't watered down?
Chad Fernandez
Michigan, USA
Ethan Dicks wrote:
It's labelled "isopropanol" in the
States.
-ethan
__________________________________________________
Do You Yahoo!?
Yahoo! Sports - Coverage of the 2002 Olympic Games
http://sports.yahoo.com
4:48 p.m.
Ethan Dicks wrote:
> It's labelled "isopropanol" in the States.
On Wed, 20 Feb 2002,
Chad Fernandez wrote:
Rubbing alcohol, that isn't watered down?
YES.
BUT, ...
Some folk on the list from other parts of the world, such as Tony, have
not seen it by that name, and would prefer to use the actual correct
chemical designations. But then again, they call their drugstores
"chemist"s :-)
You want the ~90% stuff, not the ~70%.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
20 Feb
20 Feb
10:18 a.m.
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21 Feb
21 Feb
4:59 a.m.
Kerosine based lamp-oil is one of the best for me!
(take care not to use the stuff with colors and
nice flagrances!)
Not too fat but enough to make it work and
not much of a risk regarding solving
plastics and other fragile stuff.
There is also tuner-contact-spray in case
you have to work very delicate plastic pots
This stuff is less aggressive than your run
of the mill contact-spray.
Sipke de Wal
-----------------------------------------
http://xgistor.ath.cx
-----------------------------------------
----- Original Message -----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, February 21, 2002 1:18 AM
Subject: Re: OT: cleaning pots on my vintage audio amp
Some folk on
the list from other parts of the world, such as Tony, have
not seen it by that name, and would prefer to use the actual correct
FWIW, the first time I saw the term 'Rubbing alcohol' was in an Apple ][
manual (to clean the edge connector fingers on a plug-in card). I was
`working' at a research chemical lab at the time, and the chemical stores
had no idea what 'rubbing alcohol' was (they had dozens of alcohols
available, of course). It took me quite some time to find out what was
actually needed.
chemical designations. But then again, they call
their drugstores
"chemist"s :-)
You want the ~90% stuff, not the ~70%.
I'll stick to the 99.7% stuff that comes in spray cans and is sold for
electronic/mechanical cleaning :-)
-tony
19 Feb
19 Feb
5:33 a.m.
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3:28 p.m.
Tony Duell wrote:
I'll have to look again. I probably won't do anything until this
weekend. It didn't jump out at me, last time I had the cover off. If I
recall correctly, many things were attached. I've got a Fisher that
needs work (what, I don't know), and the face plate came off that very
easily.
I don't have anything with multiple concentric spindles, on this amp,
fortunately. Looking at the amp, it really isn't the pots that are the
main problem, it's the switches. They are rotary switches, not sliding
switches. I guess that's why I was thinking pots.
Chad Fernandez
Michigan, USA
Wonderful....
I don't know if I can do that. Last time I tried cleaning
them, I couldn't figure out how to easily remove the faceplate. The
Normally you remove all the knobs and then the faceplate is held on by
one of :
Screws from the back going into tapped bushes cast into the faceplate
Screws from the top and bottom going through flanges on the faceplate
Extra nuts on a couple of the controls. How can I tell
if they are standard? Who would be the best to order new
ones from? I've never purchased components like this before.
Ah.... What I normally do is see if I can find a suitable replacement in
any of the component catalogues I have. In general, pots with multiple
concentric spindles (say volume and balance with 2 knobs one in front of
the other), pots with fixed taps along the track (i.e. more than 3
connections) and anything with more than 2 gangs are going to be hard to
find.
20 Feb
20 Feb
10:06 a.m.
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3:06 p.m.
Tony Duell wrote:
If I explode the diagrams won't they be in tiny pieces, making them much
harder to use?? :-) No, I don't have any diagrams :-(
I'll try it. Looking at the thing, yet again, I realize that I do
indeed have 1 dual concentric shafted pot. The Balance is on the same
knob as the Volume.
Chad Fernandez
Michigan, USA
I'll have to look again. I probably won't do anything until this
weekend. It didn't jump out at me, last time I had the cover off. If I
I guess I can conclude you don't have a service manual with exploded
diagrams, then :-)
Incidentally, once you're inside, look to see if the schematic is tucked
in there. It's not that uncommon to find a schematic in an envelope stuck
to the cover of 1970's stereo equipment.
I've had the cover off before. I don't recall seeing a schematic.
I don't have anything with multiple
concentric spindles, on this amp,
fortunately. Looking at the amp, it really isn't the pots that are the
main problem, it's the switches. They are rotary switches, not sliding
switches. I guess that's why I was thinking pots.
OK. Often, giving them a squirt of propan-2-ol (sorry, rubbing alcohol
:-)) and turning them vigorously back and forth will cure that.
8341
days inactive
8345
days old
28 comments
14 participants
participants (14)
-
ard＠p850ug1.demon.co.uk -
bfranchuk＠jetnet.ab.ca -
cisin＠xenosoft.com -
erd_6502＠yahoo.com -
fernande＠internet1.net -
jbmcb＠hotmail.com -
lgwalker＠mts.net -
rws＠enteract.com -
sipke＠wxs.nl -
sloboyko＠yahoo.com -
stanb＠dial.pipex.com -
tothwolf＠concentric.net -
vance＠ikickass.org -
zmerch＠30below.com