bobinaz
Active Member
I have been working on a display problem on my Sansui 990 on amd off for a few weeks now. The problem was in the function selector switch contacts. The radio display would only light up when I moved the function selector switch "between positions".
It should light up on AM, FM and Dolby FM. I used contact cleaner, De-Oxit and other sprays with no success. After using a dental pick and tweezers holding very fine sandpaper, I managed to get the lights to come on for AM and Dolby FM(sometimes) Regular FM would come on maybe once, then go off, unless I fiddled with the selector switch.
Giving credit where credit is due, I found a post on the Vintage Asylum by a J_Neutron which describes a "fix" for this problem.
The "fix" is to make the radio display lights stay on all the time when the rcvr is on. (my marantz 2325 is like this)
some quotes and paraphrase here:
"With the top cover removed, looking down on the right side, there is a pc board about 4" x 5 " that the selector switch is mounted on. On that board there are connection plugs. Second from the right there is a connector with a orange, grey, black and red wire attached. There is an open location on that connector. Move the red wire(~6.5 vac) from the end position to the vacant position next to the black wire. This new position will tap into the 6.5 vac supply that the source selector uses. Now the tuning lights will be on all the time and the orange source lights will switch on and off as the function selector changes(am,fm,phono,aux,dolby fm)
This fix was real easy, no soldering. It may not functioned as designed, but at least now the radio display lights are on and there is no compromize as far as the circuit design goes.
Now the originator was describing this for a model 9090. I have the 990 and it may work the same for the 9090db, 8080, 7070.
It was just irritating to me not to have the radio display light on. So now that they are on whenever the unit is on, that's OK.
It should light up on AM, FM and Dolby FM. I used contact cleaner, De-Oxit and other sprays with no success. After using a dental pick and tweezers holding very fine sandpaper, I managed to get the lights to come on for AM and Dolby FM(sometimes) Regular FM would come on maybe once, then go off, unless I fiddled with the selector switch.
Giving credit where credit is due, I found a post on the Vintage Asylum by a J_Neutron which describes a "fix" for this problem.
The "fix" is to make the radio display lights stay on all the time when the rcvr is on. (my marantz 2325 is like this)
some quotes and paraphrase here:
"With the top cover removed, looking down on the right side, there is a pc board about 4" x 5 " that the selector switch is mounted on. On that board there are connection plugs. Second from the right there is a connector with a orange, grey, black and red wire attached. There is an open location on that connector. Move the red wire(~6.5 vac) from the end position to the vacant position next to the black wire. This new position will tap into the 6.5 vac supply that the source selector uses. Now the tuning lights will be on all the time and the orange source lights will switch on and off as the function selector changes(am,fm,phono,aux,dolby fm)
This fix was real easy, no soldering. It may not functioned as designed, but at least now the radio display lights are on and there is no compromize as far as the circuit design goes.
Now the originator was describing this for a model 9090. I have the 990 and it may work the same for the 9090db, 8080, 7070.
It was just irritating to me not to have the radio display light on. So now that they are on whenever the unit is on, that's OK.
