Aiwa CS-600 E. HELP Needed. No Radio sound, No sound or play on cassette. Voice totally missing !

[Kris]

Hi,

I managed to open one of my newest boomboxes and tried to fix the cassette player, put the new belts on and started to put it all together when i put the screwdriver on the wrong spot (while power was on) and sound went totally missing. Few lights are still on, but nothing can be heard, no matter using Radio or cassette (cassette is not working).
I have checked both fuses and they are ok. Also i have checked both speakers and they work, cause u can hear lite hum coming from the both speakers.

I do have CS-600 service manual downloaded from the Internet, but my knowledge regarding how to check something (capacitor or something else) with a multimeter is very limited, due to i´m not electrician nor have education for it, doesn´t help the possibility to fix the problem..Although i really would like to learn

I put some pictures along of the board, if somebody would point me some advice, where to start looking the problem

Thanks

Kris

 

[hopey]

You only do this once we all have. Probably a fusible resistor if you can find it good luck.

 

[Kris]

Yes. Really hitting my head against the wall with this one... Frustration is on the air

 

[Tinman]

Thankfully this hasn't happened to me, yet.
Personally, I'd start from where the screwdriver shorted.
Even if your eyes are good, a magnifying glass could be helpful.

 

[floyd]

The place I would look would be at the amplifier chips that was probably should be tested first even if something's bad they could still put out a hum. In most cases if you short circuit in amplifier that's it the IC chips are done and probably some of the transistors if it has them.

 

[Hisrudeness]

As Floyd says. I’d start with amp chip.

 

[Kris]

Do you mean this part ? I do lack "knowhow" how to check an amp ? But when touching the two long row of soldered points, it does affect on speakers, both right and left speaker make loud scratch sound when the screwdriver hits on to some points, but nothing more. How should i proceed ? Towards success, i hope

 

[floyd]

Thankfully this hasn't happened to me, yet.
Personally, I'd start from where the screwdriver shorted.
Even if your eyes are good, a magnifying glass could be helpful.

I agree if you backtrack along where the screwdriver make contact you can tell which circuits might have been affected.

 

[floyd]

Do you mean this part ? I do lack "knowhow" how to check an amp ? But when touching the two long row of soldered points, it does affect on speakers, both right and left speaker make loud scratch sound when the screwdriver hits on to some points, but nothing more. How should i proceed ? Towards success, i hope

That looks like the amplifier section the piece of aluminum sticking out of the board is the amplifier heat sink the amplifier IC chips are mounted to the heatsink and go into the circuit board. I guess the first thing you should do is check the board and the parts for any visible damage. Also don't be afraid to sniff around because sometimes you can smell what you can't see.

 

[Superduper]

The most likely components that will fail from stray screwdriver tip contacts are going to be semiconductors, such as transistors and diodes. IC chips are made of scores of transistors and diodes encapsulated within. When you short a transistor emitter to ground, it will blow in microseconds. That's why you never probe around in a live circuit without knowing exactly what you are doing. Even technicians that know what they are doing still occassionally damage components when the probe slips or they probed the wrong solder pad. Now whether it was an accidental contact (like your original scenario) or a purposeful deliberate contact (like what you are currently doing to the IC chips), short the wrong point AND IT WILL BLOW. If you haven't already, continued probing is a sure way to brick your circuit for good. BTW, randomly shorting amp chip pins to illicit a response is like blow torching an ant to see if it's still alive. What if there was crackling... did you just blow it in the process? Or did you just happen to short a power pin to the speaker pin therefore making an audio response?

 

[Tinman]

Agreed that probing with a screwdriver is a baaaad idea.
Noise in the speakers will come from touching various places on the board, that doesn't mean you're in the right spot.
You have a service manual, now you need a multimeter.

 

[Radio raheem]

I did exactly this with a hifi donkeys years ago and blew a huge hole in the circuit board, lesson learnt....baaaaaaaaad idea

i then took the hifi in for repair expecting doom but somehow they repaired it so all good

 

[Radio raheem]

hate saying it but i once was poking an old record player insides with a knife when i was about 9....i had a huge shock and i was actually thrown off the stage...the end of the knife was melted....the only thing i can say for certain is the handle of the knife was wood, that was the only thing that saved me so think again lol

 

[Kris]

I agree, very bad idea to mess a circuit board or these soldered pads with a screwdriver but the damage has already done so...who to blame, well.. me, myself & i I have a very simple multimeter, in what position it has to be when checking e.g. transistors or diodes and most importantly what the multimeter should tell you in numeric values ? If some of you have downloaded the CS-600 service manual as i, do u have any suggestions what part (s) should i check first ??

By the way, i checked the board with a magnifying glass and found nothing that seemed to be burned or had a specific distinctive appearance...so, what does that tell.. Sometimes, if it ain´t easy, it ain´t easy...

 

[Radio raheem]

Most of us have been there buddy so don't worry ehh....hope you can get her sorted but even someone like me is a novice even after all these years

 

[floyd]

hate saying it but i once was poking an old record player insides with a knife when i was about 9....i had a huge shock and i was actually thrown off the stage...the end of the knife was melted....the only thing i can say for certain is the handle of the knife was wood, that was the only thing that saved me so think again lol

Well my sister tried to defrost the freezer with a screwdriver yeah about 5 minutes into it it started hissing Freon out lol.

 

[Radio raheem]

Well my sister tried to defrost the freezer with a screwdriver yeah about 5 minutes into it it started hissing Freon out lol.

Try working on one of those old big shitty tv's from the 80's without draining the caps first lol....i never touched one of those again either lol..........i should start my own mr bean episodes on youtube with my mate downstairs homie...............i could have made millions lol...it would be called Mr braindead rides again lol

 

[floyd]

Try working on one of those old big shitty tv's from the 80's without draining the caps first lol....i never touched one of those again either lol..........i should start my own mr bean episodes on youtube with my mate downstairs homie...............i could have made millions lol...it would be called Mr braindead rides again lol

Try pulling a spark plug wire off of running V8 motor that motherfuker will make you the first drunk in space like I was lol.

 

[Radio raheem]

Try pulling a spark plug wire off of running V8 motor that motherfuker will make you the first drunk in space like I was lol.

Try building some speakers like we have just done lad lol...i can't even have it past number 1 without the room shaking lol i hate you jk

 

[floyd]

Try building some speakers like we have just done lad lol...i can't even have it past number 1 without the room shaking lol i hate you jk

Imagine putting those in the back of a Cooper Mini with 3000 watts of power.