It is currently Mon Mar 16, 2020 9:01 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 30 posts ]  Go to page 1, 2  Next
Go to page 1, 2  Next
Author Message
Post subject: bright switches not working properly on 1968 Fender Twin
Posted: Tue Jul 23, 2019 10:49 am
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 23, 2019 9:39 am
Posts: 28
Hi,
The bright switches on my 1968 Fender Twin only work in the bright (up) position when I put slight pressure on them, pushing gently into the amp. I was going to try spraying them from the front of the amp with the same Deoxit D5 that I used to clean the knobs (also from the front), to see if that might work. Can that spray be used on the switches?
I've never opened the amp myself, don't feel confident doing it safely, and don't want to take it to the local shop, they seem to be inexperienced.
Any help would be appreciated.


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Wed Jul 31, 2019 8:49 pm
Offline
Professional Musician
Professional Musician

Joined: Thu Aug 07, 2014 3:25 pm
Posts: 1023
While a de-oxit spray may eventually clean the contact, I prefer exercising the switch.
A metal to metal burnishing gives immediate results.
Flip the switch on and off, while the unit is OFF, 100 times briskly. This should help and stay clean.


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Wed Jul 31, 2019 10:48 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
TimsAudio wrote:
While a de-oxit spray may eventually clean the contact, I prefer exercising the switch.
A metal to metal burnishing gives immediate results.
Flip the switch on and off, while the unit is OFF, 100 times briskly. This should help and stay clean.

+1

If the above procedure does not offer relief, it's possible that the switches themselves are shot (they are some fifty-one years old after all). My '68 Bronco's power switch -- the identical slider as used for bright switches -- flaked out a couple of years back due to the same geriatric syndrome. They're easy enough to replace and not very expensive.

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 8:42 am
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 23, 2019 9:39 am
Posts: 28
TimsAudio wrote:
While a de-oxit spray may eventually clean the contact, I prefer exercising the switch.
A metal to metal burnishing gives immediate results.
Flip the switch on and off, while the unit is OFF, 100 times briskly. This should help and stay clean.

Thanks for the reply. I already sprayed the de-oxit from the front and both switches now work normally, but I am now going to flip the switch briskly, that makes sense. The amp has not been used for awhile so I guess those switches need to be exercised.


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 8:49 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
Cool!

Use some De-Oxit on a Q-tip and clean all the input jacks and speaker jacks as well just to be thorough.

Rawk on.

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 9:50 am
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 23, 2019 9:39 am
Posts: 28
Retroverbial wrote:
Cool!

Use some De-Oxit on a Q-tip and clean all the input jacks and speaker jacks as well just to be thorough.

Rawk on.

Arjay

OK! That was my next question!
I didn't want to spray into the jacks and feel stupid for not thinking about using a Q-tip.
This is my first time using De-Oxit. Thanks for the idea!


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 10:27 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
No problem. De-Oxit evaporates pretty quickly so there's really no hazard as long as the amp is powered down and unplugged.

You might do the RCA phono jacks and plugs for the reverb tank and foot switch as well.

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 11:04 am
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 23, 2019 9:39 am
Posts: 28
Retroverbial wrote:
No problem. De-Oxit evaporates pretty quickly so there's really no hazard as long as the amp is powered down and unplugged.

You might do the RCA phono jacks and plugs for the reverb tank and foot switch as well.

Arjay

OK, I'll do everything, I didn't think about the RCA jacks and plugs.
Thanks.


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Thu Aug 01, 2019 12:42 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
You're quite welcome.

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 1:09 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14045
Location: Province de Québec, Canada
I must admit that my information does not come from scientific studies.

Maybe it's in the same category that if you use an amplifier it will help to damage it.
To be safe we must live the amp in the box :lol:


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 2:21 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Feb 13, 2018 10:28 pm
Posts: 1594
Location: SoCal, US
Another thing about slide switches... The contacts are on a fiber board that is held onto the back of the switch by tabs bent down from the sides.
Over time, particularly by people who are heavy handed, these tabs can become straightened, causing the board to back away from the contacts on the plastic part of the switch.
I have mixed feelings on slide switches... they are pretty reliable in that they are self-cleaning because the contacts wipe across each other as the switch is operated... but the mechanical aspects are a drawback for something that is used frequently, such as a power switch.

If the switch feels at all "stiff" or seems to be binding, it's worth looking at the back to confirm that the tabs are properly bent and holding the board in place. The switch only working when you press on it is a sign that this is the problem.

Image

_________________
-- Rich


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 3:32 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14045
Location: Province de Québec, Canada
CB91710 wrote:
Another thing about slide switches... The contacts are on a fiber board that is held onto the back of the switch by tabs bent down from the sides.
Over time, particularly by people who are heavy handed, these tabs can become straightened, causing the board to back away from the contacts on the plastic part of the switch.
]


I will be very surprised that this is happening. People do not keep pressing the button continuously for a long time.
It lasts a second when the button is pressed.

And finally we use these buttons very rarely. That's why contact gets oxidized and we need cleaning.


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 4:17 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Feb 13, 2018 10:28 pm
Posts: 1594
Location: SoCal, US
stratele52 wrote:
CB91710 wrote:
Another thing about slide switches... The contacts are on a fiber board that is held onto the back of the switch by tabs bent down from the sides.
Over time, particularly by people who are heavy handed, these tabs can become straightened, causing the board to back away from the contacts on the plastic part of the switch.
]


I will be very surprised that this is happening. People do not keep pressing the button continuously for a long time.
It lasts a second when the button is pressed.

And finally we use these buttons very rarely. That's why contact gets oxidized and we need cleaning.

It is a 50 year old amplifier, and the switch works when he presses on it.
I've seen these switches fail in this manner in traffic signal equipment that is rarely manipulated.

_________________
-- Rich


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 4:30 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14045
Location: Province de Québec, Canada
CB91710 wrote:


It is a 50 year old amplifier, and the switch works when he presses on it.
I've seen these switches fail in this manner in traffic signal equipment that is rarely manipulated.


Switch just need to be clean wit good contact cleaner.


Top
Profile
Post subject: Re: bright switches not working properly on 1968 Fender Twin
Posted: Sun Aug 04, 2019 5:17 pm
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 23, 2019 9:39 am
Posts: 28
CB91710 wrote:
Another thing about slide switches... The contacts are on a fiber board that is held onto the back of the switch by tabs bent down from the sides.
Over time, particularly by people who are heavy handed, these tabs can become straightened, causing the board to back away from the contacts on the plastic part of the switch.
I have mixed feelings on slide switches... they are pretty reliable in that they are self-cleaning because the contacts wipe across each other as the switch is operated... but the mechanical aspects are a drawback for something that is used frequently, such as a power switch.

If the switch feels at all "stiff" or seems to be binding, it's worth looking at the back to confirm that the tabs are properly bent and holding the board in place. The switch only working when you press on it is a sign that this is the problem.


Thanks for the picture and for explaining how the switch works and how the tabs can become straightened. That makes sense.
I sprayed the switches from the front and they're working fine now. The amp hasn't been used for years so maybe the contacts just needed cleaning.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 30 posts ]  Go to page 1, 2  Next
Go to page 1, 2  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: