diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Car Audio (http://www.diyaudio.com/forums/car-audio/)
-   -   Alpine MRV-1505 (http://www.diyaudio.com/forums/car-audio/227673-alpine-mrv-1505-a.html)

seankane 13th January 2013 04:47 AM

Alpine MRV-1505
 
Have this amp for repair.

When the phase switch is at 0 channel 1 works great channel 2 is dead, when the phase switch is at 180 channel 2 works great and channel 1 is dead.

Any ideas?

Perry Babin 13th January 2013 05:31 AM

Do you have audio on pin 8 of IC106 and IC206?

seankane 13th January 2013 06:12 AM

I have audio on #8 of 206, but no audio on #8 of 106.

Perry Babin 13th January 2013 07:02 AM

Do you have audio on any of these points?

IC103 - pin 8
IC103 - pin 2
IC102 - pin 8
IC106 - pin 2

seankane 13th January 2013 08:37 PM

Quote:

Originally Posted by Perry Babin (Post 3323466)
Do you have audio on any of these points?

IC103 - pin 8
IC103 - pin 2
IC102 - pin 8
IC106 - pin 2

I have audio on all the pins except for pin #2 of IC106.

Perry Babin 14th January 2013 03:03 AM

1 Attachment(s)
Check the crossover, stereo/mono and phase switches for the defective channels with a multimeter to confirm that all contacts ion all positions are making proper contact. Attached is a photo of the 3-position switches. I'm assuming that you know how the 2-position switches work.

seankane 14th January 2013 03:42 AM

1 Attachment(s)
OK the switches do not operate the channels seperately, the switches control both channels at once. I am not 100% how to check the switches with the multimeter.

The phase switch is the only switch that has any effect on the audio signal and its a 2 position switch.

I have posted a pic of the output section.

Perry Babin 14th January 2013 04:34 AM

Look at the image. The slider moves between the contacts. You should read 0 ohms between the two contacts with the slider touching them. Check all 3 switches.

seankane 14th January 2013 04:36 AM

OK one more question, what are the 2 red LED lights that are lit up on the board in the output section?

Perry Babin 14th January 2013 04:41 AM

They are used as a voltage reference for a constant current source.


All times are GMT. The time now is 03:08 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2