Go Back   Home > Forums > General Interest > Car Audio

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 5th May 2011, 04:50 AM   #1
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
Default Alpine MRV-F307

I recieved this amp with one channel not producing any sound but all the other 3 channels worked great. I replaced 2 output fets that were burnt. I powered up the amp and it powers on and the LED stays lit. The amp pulses on my power supply. It produces sound in all channels but goes on and off. You can see the current draw then nothing. Its like the power supply is turning on and off over and over again. The LED stays lit the whole time and is green.

Does anyone have any clues for me??
  Reply With Quote
Old 5th May 2011, 05:05 AM   #2
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Is there any pulsing DC on the dead channel?

Did you check the drivers for the outputs?

Are the emitter/source resistors within tolerance?
  Reply With Quote
Old 5th May 2011, 05:11 AM   #3
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
Quote:
Originally Posted by Perry Babin View Post
Is there any pulsing DC on the dead channel?

Did you check the drivers for the outputs?

Are the emitter/source resistors within tolerance?
The dead channels produces audio as well as the other 3. The sound goes on for 3 seconds then off for 3 seconds over and over. Its like the power supply is shutting on and off but the LED stays lit green the whole time.

Drivers you mean the little 1/8 watt 220 ohm rsistors?

The emitters you mean the 5 watt 0.1 ohm ceramic/stone looking resistors?
  Reply With Quote
Old 5th May 2011, 05:14 AM   #4
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
All channels produce sound but shut on and off.

I dont see any DC on the channels but they do make a pop when you connect a speaker.

I am not at all familiar with Alpine amps.
  Reply With Quote
Old 5th May 2011, 05:33 AM   #5
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
After re-checking for dc using the terminals inside the amp instead of the screws I do find a pulsing of DC. Channel 3 bridging terminal pulses up to 1.5 vdc and channel 4 bridging terminal pulses up to 14.50 vdc.
  Reply With Quote
Old 5th May 2011, 05:36 AM   #6
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
The emitters and drivers seem to be OK and within tolerance one of the drivers was at 215.5 ohms seems a little low. It looks as if they use one driver and one emitter per pair of fets. Thats seems strange to me. There are 4 drivers and 4 emitters, but 8 output fets.
  Reply With Quote
Old 5th May 2011, 12:37 PM   #7
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Do the emitter resistors have 3 legs?

Did you lift the transistor to see if it was leaking or if the 215 ohms was from something else on the board?
  Reply With Quote
Old 5th May 2011, 05:13 PM   #8
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
The emitter resistors do have 3 legs. I have not pulled the transistor since they were installed new. I dont know why they would be leaking unless I bought bad ones. I can pull them to be sure if needed. I have not checked anything else yet.
  Reply With Quote
Old 5th May 2011, 05:56 PM   #9
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
If it reads differently than the others on the board, you'll probably have to remove it to determine if it's the transistors or another component on the board.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Alpine MRV-1000 yet again spooney Car Audio 39 18th May 2013 11:07 PM
Alpine MRV 1507 FSUSeminole Car Audio 8 1st January 2011 07:04 PM
Alpine MRV-F401 or MRV-F400 Service Manual M.André Car Audio 6 21st February 2010 09:37 PM
Alpine MRV-F307 Tweaks RyanW Car Audio 22 9th March 2008 10:19 PM
working on a alpine mrv jol50 Car Audio 49 16th December 2007 05:26 AM


New To Site? Need Help?

All times are GMT. The time now is 05:54 AM.


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