anderslober
Yikes...not again!
QQ: lamp changed......tuner works fine.......tuning center/signal works fine.....no stereo light.............any ideas?
(I hate tuners!:sigh
(I hate tuners!:sigh
Pioneer sx9000 stereo light indicator.
- Thread starter anderslober
- Start date
Call the local stations and ask them if they are transmitting in MONO or STEREO! :tongue:
Check the voltages on either side of the lamp..Once side will go to the tuner or mpx board, and the other should go to the P.S. You can simulate MONO by detuning the station slightly while checking the voltages...
Check the voltages on either side of the lamp..Once side will go to the tuner or mpx board, and the other should go to the P.S. You can simulate MONO by detuning the station slightly while checking the voltages...
anderslober
Yikes...not again!
Either side of lamp is 21.5V.......no change when tuning. So somehting isnt doing what it should. I guess the lamp runs on diff-voltage......which tr controls this on the MPX board? Q5...2sc711. Signal seems and sounds strong.
Edit: The manual states that the stereo bulb is a 6v/30mA device........initially I put in this rating and got nothing. Then I put in a 9v LED.....I got flashes of light......I then put in a 8v/50mA bulb and was able to get a light reaction/flash. When I tune a strong station....still no stereo light......when I slightly de-tune said strong station(with a lot of distortion), I can get the bulb to light up.
Its just not logical to me.......damn tuners........:-(
Edit: The manual states that the stereo bulb is a 6v/30mA device........initially I put in this rating and got nothing. Then I put in a 9v LED.....I got flashes of light......I then put in a 8v/50mA bulb and was able to get a light reaction/flash. When I tune a strong station....still no stereo light......when I slightly de-tune said strong station(with a lot of distortion), I can get the bulb to light up.
Its just not logical to me.......damn tuners........:-(
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If you are detuning and getting a flicker on the stereo light, the tuner needs an alignment, along with the MPX.
anderslober
Yikes...not again!
I was hopin' you wouldn't say that...... Shucks.......I have run into 3 different tuners with problems, within a couple of weeks........:-(
I have not touched any of the vr's/cores..........
I have strong signal indicated where it should be on the dial...........just no stereo light...detune a bit and the light flickers.......there must be something simple we do to 'align'.............
I have not touched any of the vr's/cores..........
I have strong signal indicated where it should be on the dial...........just no stereo light...detune a bit and the light flickers.......there must be something simple we do to 'align'.............
anderslober
Yikes...not again!
Ok guys........deep, deep thought has preceded the next theory.
As this unit is choke full of 'shields'.......could it be a simple shielding problem? The unit is quite sensitive to hand movement near the MPX board. I can create quite a bit of hum by just holding my hand close to the MPX board.......
Whaddya' think..........?
The unit tunes fine.....and when using a 8v/50mA bulb, I can get the stereo light to light up.....with a lot of distortion. So, we must be able to 'tweak' this out............
As this unit is choke full of 'shields'.......could it be a simple shielding problem? The unit is quite sensitive to hand movement near the MPX board. I can create quite a bit of hum by just holding my hand close to the MPX board.......
Whaddya' think..........?
The unit tunes fine.....and when using a 8v/50mA bulb, I can get the stereo light to light up.....with a lot of distortion. So, we must be able to 'tweak' this out............
anderslober
Yikes...not again!
I did already........nothing.
6/30ma vs 8v 50ma isn't usually very significant. A LED however...
q5's C4 (3.3uf) new? if not - make it so.
q5's C4 (3.3uf) new? if not - make it so.
anderslober
Yikes...not again!
Ok Mark....will do.....
blhagstrom
Mad Scientist, fixer.
I'm not a fan of tuner work but it happens.
This beacon system appears to be the grounding type.
Supply voltage is present at the lamp.
When stereo signal decoding is detected the lamp gets ground.
This beacon system appears to be the grounding type.
Supply voltage is present at the lamp.
When stereo signal decoding is detected the lamp gets ground.
anderslober
Yikes...not again!
I changed C4 at q5.......still nothing. Then I changed all the caps on the MPX, mute and FM board.........still nothing. IRRITATING PROBLEM THIS! The tuner works fine. Stations are clear. The position on the tuner dial corresponds to the station.
The stereo light DOES work.....so, I guess the decoder works....just not on the clear stations........:-(
What about my 'shielding theory'................I will put all the shields on and see......
The stereo light DOES work.....so, I guess the decoder works....just not on the clear stations........:-(
What about my 'shielding theory'................I will put all the shields on and see......
