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asimov_18
09-19-2010, 11:50 PM
Hi guys,
I experience strange problem using many old electronic appliances. For example I have a panasonic HiFi system with CD,cassette and FM. The problem is as these gadget get old they function erratically, suppose I press the play button for the cassette the player at times Fast forward function gets enabled (the btton just next to play). I mean the logic seems to get weired and mixed up. I faced similar problems with other electronic items as well and this happens only as they get old!!!!

I presume this should be because of failing soldering joints inside the system as it ages created intermitent contact. Could it be because of other problems ?

Asimov

allbits
09-20-2010, 01:34 AM
what kind of switches are they? mechanical, or membrane?

asimov_18
09-20-2010, 07:33 PM
They are not membrane switches, but of the types which are soldered on the PCB, square in shapes with 4 legs.

Asimov

yaniv
09-21-2010, 08:20 AM
How old is your cassette player? i've come across this kind of problem but its never been persistent.
Push button switches.. Switches aren't jammed right? ;)

allbits
09-21-2010, 11:39 PM
must be a contact problem. Nothing else. Cleaning and resolder would do.
Cant find any other reason.

docel
09-23-2010, 09:00 PM
Those are tactile switches , i think....do they make a clicking sound when depressed ?
Most of them are 'dome' switches with a convex spring metal disc. Most of these switches are readily available locally and can be replaced.

If it doesnt 'click' then they are the 'soft touch' carbon screen printed contacts , like the TV Remotes. Cant do much about them , though you do get Carbon conductive ink.

asimov_18
09-23-2010, 10:38 PM
Hey docel,
yes they are the clicking type of switches. I guess the problem is more with dried solder joints rather than the switches themselves. Recently I had to resolder the power amplifier IC pins as some contacts had become intermittent.

Asimov