Becker Mexico Radio Cassette Vollstereo 485 - UK Vintage Radio Repair and Restoration Discussion Forum

Soleyman · 24th Mar 2024, 8:17 am

Hi,

It's been a while that I'm trying to fix my car radio. The radio on AM/FM plays very low and noisy even at full volume but the cassette works fine and the sound quality and volume is very well. I replaced all the capacitors on the radio and AMP but it didn't help. When I push the search bar (Wunderbar) it goes to the next channel so I believe there is no signal issue. Unfortunately I couldn't find any technical diagram for this specific model. There is a switch on the cassette section that I think is the switch over to the radio. I checked that and it seems to be good. The switch has three wires. One is ground, second is connected to a lamp and third wire connected to the decoder board. When the cassette player is active the light is off and the third wire has 12 volts. On AM/FM the light is on and the wire has 0.5 volt.
I'm not an audio expert but I have some knowledge in computer field. I found another topic with almost the same issue but it was closed so I couldn't post there:
https://www.vintage-radio.net/forum/....php?p=1529526
Let me know if you have any idea about this issue. Any help would be appreciated. Thanks in advance.

Soleyman

Soleyman · 24th Mar 2024, 7:28 pm

Here is a photo of the unit and the switch:

Robert Gribnau · 24th Mar 2024, 9:20 pm

Please share the document from which you got your third picture.

Soleyman · 25th Mar 2024, 7:41 am

Quote:

Originally Posted by Robert Gribnau

Please share the document from which you got your third picture.

It comes from the "Becker Mexico Cssette Vollstereo" technical manual which is similar to this unit. Thanks.

I couldn't upload the file because it is a 11MB PDF file but you can find it online.
Let me know if you need a link. Thanks.

marceljack · 25th Mar 2024, 2:24 pm

There might be a problem in the stereo decoder or its connections which could attenuate the audio signal between the radio part and the amplifiers.

Soleyman · 26th Mar 2024, 6:41 am

Thanks for your reply. Could you please take a look at the following photos of the decoder board and let me know which part might be bad and what should I check first. Thanks in advance.

24th Mar 2024, 8:17 am	#1
Soleyman Diode Join Date: Mar 2024 Location: Burnaby, British Columbia, Canada. Posts: 5	Becker Mexico Radio Cassette Vollstereo 485 Hi, It's been a while that I'm trying to fix my car radio. The radio on AM/FM plays very low and noisy even at full volume but the cassette works fine and the sound quality and volume is very well. I replaced all the capacitors on the radio and AMP but it didn't help. When I push the search bar (Wunderbar) it goes to the next channel so I believe there is no signal issue. Unfortunately I couldn't find any technical diagram for this specific model. There is a switch on the cassette section that I think is the switch over to the radio. I checked that and it seems to be good. The switch has three wires. One is ground, second is connected to a lamp and third wire connected to the decoder board. When the cassette player is active the light is off and the third wire has 12 volts. On AM/FM the light is on and the wire has 0.5 volt. I'm not an audio expert but I have some knowledge in computer field. I found another topic with almost the same issue but it was closed so I couldn't post there: https://www.vintage-radio.net/forum/....php?p=1529526 Let me know if you have any idea about this issue. Any help would be appreciated. Thanks in advance. Soleyman

24th Mar 2024, 7:28 pm	#2
Soleyman Diode Join Date: Mar 2024 Location: Burnaby, British Columbia, Canada. Posts: 5	Re: Becker Mexico Radio Cassette Vollstereo 485 Here is a photo of the unit and the switch: Attached Thumbnails

24th Mar 2024, 9:20 pm	#3
Robert Gribnau Banned Join Date: May 2017 Location: Konongo, Ghana Posts: 516	Re: Becker Mexico Radio Cassette Vollstereo 485 Please share the document from which you got your third picture.

25th Mar 2024, 2:24 pm	#5
marceljack Pentode Join Date: Apr 2021 Location: Paris, France. Posts: 247	Re: Becker Mexico Radio Cassette Vollstereo 485 There might be a problem in the stereo decoder or its connections which could attenuate the audio signal between the radio part and the amplifiers.

26th Mar 2024, 6:41 am	#6
Soleyman Diode Join Date: Mar 2024 Location: Burnaby, British Columbia, Canada. Posts: 5	Re: Becker Mexico Radio Cassette Vollstereo 485 Thanks for your reply. Could you please take a look at the following photos of the decoder board and let me know which part might be bad and what should I check first. Thanks in advance. Attached Thumbnails