Rockford Fosgate Power 800.4 - Page 3 - diyAudio
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 10th January 2012, 03:35 AM   #21
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Black probe on source of Q110. Red probe on base of Q121. What's the DC voltage?
  Reply With Quote
Old 10th January 2012, 03:44 AM   #22
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
+1.965 vdc
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 03:53 AM   #23
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Q122 appears to be open.
  Reply With Quote
Old 10th January 2012, 04:04 AM   #24
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
I replaced it with same result still have the -35.67 dc on the bridging terminal

Without Q106 and Q105 in the circuit I had 50 vdc on the bridging terminal.
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 04:08 AM   #25
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
I thought that you had -37 with Q105 and Q106 out of the circuit (post #18).

I assumed that the voltage on the base of Q122 was at or below the voltage on the base of Q121. If that was so, the transistor would have to be open if you read 40 ohms between the gate of Q110 and the emitters of the drivers. The base of the PNP driver can't be that far below the emitter unless it's defective.
  Reply With Quote
Old 10th January 2012, 04:12 AM   #26
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
I did have -37 with Q105 and Q106 out of the circuit until I replaced Q122 then I had 50 vdc. Installing Q105 and Q106 back into the circuit brought it back down to -37 again.
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 04:20 AM   #27
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
A pic of section I am working on.
Attached Images
File Type: jpg Power 800.4 001.jpg (1,007.3 KB, 26 views)
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 04:32 AM   #28
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
When I recieved the amp there was a jumper wire from the circled areas which allowed Q110 and Q123 to read the same resistance as the rest of the outputs gate to source. The voltage was still present though.
Attached Images
File Type: jpg Power 800.4 001.jpg modified.jpg (466.8 KB, 24 views)
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 04:33 AM   #29
diyAudio Member
 
seankane's Avatar
 
Join Date: May 2010
Location: Washington State
R139 to the emitter of Q116

Dont know why but I thought I would mention it.
__________________
Pyramid 52 Amp Power Supply----Fluke 787 Processmeter----Tektronix 465 Scope----Velleman HPS40 Scope----Soldering Iron----Desoldering Iron----Hejet HJ 500-S Heatgun----DM4070 Digital LCR Meter----Propane Torch
  Reply With Quote
Old 10th January 2012, 04:45 AM   #30
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
The jumper was shorting the drive voltage to the drivers.

Leave Q105 and Q106 out of the circuit.

When you had 50v, if you touched a dummy load to the speaker terminals, would the amp draw excessive current?

clamp the outputs before trying this.

Do you have any new RCA jacks for the amps like the T20001BD?

Or do you know what they cost from Rockford?
  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
Rockford Fosgate 800 a2 mike49504 Car Audio 1 8th July 2011 06:33 PM
rockford fosgate punch 800 a2 ernie cosillos Car Audio 3 12th June 2011 01:41 AM
Rockford Fosgate Power 20001 bd amplifier power rating?? pachoorion Car Audio 8 8th May 2011 10:49 PM
Rockford Fosgate 800.2 Brain Fried Car Audio 2 16th April 2010 05:14 PM
Rockford Fosgate Power 800.4 lostamps Car Audio 6 2nd January 2008 12:21 PM


New To Site? Need Help?

All times are GMT. The time now is 01:10 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