Vintage Luxman r115 receiver on sound from FM/AM.

[kuer]

Hello, I had posted this thread in another website, but haven't got any suggestion. believe here is a good place to solve the issue. Thank you.

Have a Luxman r115 for 2 years, the tuner doesn't work since I got it.

CD and other sources work great. Tuner has issues, when I push in either FM or AM button, both red indicators light up simultaneously and both indicators stay on ( should be only one indicator light on accordingly , see pic. ), but no sound at all from FM or AM, some static noise when voluming up in high level.

Can tune(scan) automatically but no station/signal found, also can pick up a station manually but silent.

In a word, no sound from FM/AM, both indicators (FM and AM) are on when selecting either FM or AM.

Inspected and cleaned buttons and pots inside and outside, no improvement.

Seek some advices here, possible reasons.

Thank you very much.

 

[east electronics]

option 1
Once the machine was sprayed with the wrong contact spray which most of it is still inside the switch work that out
Option 2
The switch is busted resulting wrong voltage ( s) fed to the tuner boards you need to work out exactly how the switches are working ( may as well hardwire any of them to FM only )

Obviously this is where my mind goes it could be a million other things still this generation of Luxman often has plenty of problems with these micro switches

 

[kuer]

option 1
Once the machine was sprayed with the wrong contact spray which most of it is still inside the switch work that out
Option 2
The switch is busted resulting wrong voltage ( s) fed to the tuner boards you need to work out exactly how the switches are working ( may as well hardwire any of them to FM only )

Obviously this is where my mind goes it could be a million other things still this generation of Luxman often has plenty of problems with these micro switches

Thanks. I checked again, almost damaged the other parts, that is what I can do.

It's hard to figure out like you said. Will leave it for, CD and others inputs are good, and sounding is good. Maybe someday I will buy another one once I have a chance.

Thanks again.

 

[orbanp]

The service manual is available at hifiengine.com: Luxman R-115 Manual - Digital Synthesized AM/FM Stereo Receiver - HiFi Engine
The datasheet on the PLL chip (LM7000), the core of the receiver is also available: LM7000 datasheet pdf datenblatt - Sanyo Semicon Device - Direct PLL Frequency Synthesizer for Electronic Tuning ::: ALLDATASHEET :::
With the help of these you can start checking out things in the AM/FM section.
You would need at least a scope for that though.

Good luck, Peter

 

[kuer]

The service manual is available at hifiengine.com: Luxman R-115 Manual - Digital Synthesized AM/FM Stereo Receiver - HiFi Engine
The datasheet on the PLL chip (LM7000), the core of the receiver is also available: LM7000 datasheet pdf datenblatt - Sanyo Semicon Device - Direct PLL Frequency Synthesizer for Electronic Tuning ::: ALLDATASHEET :::
With the help of these you can start checking out things in the AM/FM section.
You would need at least a scope for that though.

Good luck, Peter

Thanks, Peter.

Since several days ago I cleaned inside, unluckily it develped a new issue, when I turn it on at low volume, the both channels get unbalanced, one has no sound or very tiny sound, the other channel is ok, once I volume up enough, both channels start to work normally, at this time, even I volume down agian to very low, still good.

But, if the receiver stays at high volume level when starting up, no this issue.

I used a tin of wd40 to spray everything inside, maybe this caused the issue on the speaker relay.

R115 is pretty good for me, I tried several 2ch receivers, nothing better than r115. I may look to buy another one.

Thank you for your information.

 

[sgrossklass]

Plain WD-40 is best kept away from electronics.