|
|||||||
| Home | Forums | Rules | Articles | Store | Gallery | Blogs | Register | Donations | FAQ | Calendar | Search | Today's Posts | Mark Forums Read | Search |
  |
|
|
|
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 |
 |
|
|
Thread Tools | Search this Thread |
19th December 2011, 08:16 PM
|
#1 |
|
diyAudio Member
Join Date: Sep 2010
|
MTX Thunder801d
Replaced the input caps in this thing a few months ago but it back with different problems. Amp powers up, red light is on but no audio. There looks to be some damage to some surface mount resistors R139 R140 R142. They have some very small burn marks on them. Has anyone seen these go before and know the value?
|
|
|
20th December 2011, 12:38 AM
|
#2 |
|
diyAudio Member
Join Date: Nov 2003
Location: Louisiana
|
It sounds like the power supply may have failed. Are these the gate resistors for the power supply FETs?
If you're not sure, post a photo of the resistors and the area around them.
__________________
Links >> Basic Car Audio Amp Repair --- Basic Car Audio Electronics --- Basic Transistor Testing --- Basic Switching Power Supply Design --- Basic Computer Skills << Links |
|
|
|
20th December 2011, 03:43 AM
|
#3 |
|
diyAudio Member
Join Date: Sep 2010
|
They seem to be in a pre drive if there is such a thing in class D. Checked voltages on the output fets. I only see -60 vdc but the power supply seems to be generating +/- 60vdc. The fets are not shorted but maybe tomorrow I'll pull them and check them on my tracker.
|
|
|
|
20th December 2011, 04:30 AM
|
#4 |
|
diyAudio Member
Join Date: Nov 2003
Location: Louisiana
|
140 and 142 are likely 475 ohms. 139 is likely a 221 ohm. These values are from a 6500D which is very similar.
Carefully check the small parallel PNP driver transistors adjacent to the PZTA42 transistors.
__________________
Links >> Basic Car Audio Amp Repair --- Basic Car Audio Electronics --- Basic Transistor Testing --- Basic Switching Power Supply Design --- Basic Computer Skills << Links |
|
|
|
23rd December 2011, 08:02 PM
|
#5 |
|
diyAudio Member
Join Date: Sep 2010
|
Finally had a chance to look at this thing again. Removed the 2 transistor and Q116 is shorted. Any idea what I could replace them with. I wouldn't mind standing up some to92 cases if I knew the specs.
|
|
|
|
23rd December 2011, 09:53 PM
|
#6 |
|
diyAudio Member
Join Date: Nov 2003
Location: Louisiana
|
MMBT5401.
__________________
Links >> Basic Car Audio Amp Repair --- Basic Car Audio Electronics --- Basic Transistor Testing --- Basic Switching Power Supply Design --- Basic Computer Skills << Links |
|
|
|
29th December 2011, 01:46 PM
|
#7 |
|
diyAudio Member
Join Date: Sep 2010
|
Thanks for all the great info Perry. I will let you know how it goes when I get the parts in it.
|
|
|
|
| Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
| Thread Tools | Search this Thread |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| MTX thunder801d | fragmental | Car Audio | 3 | 16th March 2011 05:02 PM |
| Help MTX TA3401 | Cain | Car Audio | 9 | 3rd March 2011 02:43 AM |
| orion hcca250r, kicker zr 1000, mmats d800.2, mtx 6500d, mtx 942, rockford punch 45, | ernie cosillos | Swap Meet | 3 | 12th February 2011 11:14 AM |
| Help me fix MTX 152 and MTX 500D | hakentt | Car Audio | 94 | 8th December 2008 06:26 PM |
| New To Site? | Need Help? |
| Page generated in 0.07738 seconds (73.20% PHP - 26.80% MySQL) with 11 queries |
