Posted 05 August 2013 - 04:31 PM
I have a XTi4000 that will not switch on. I purchased it on 31/05/2010 from an Ebay company which has since ceased trading. Upon contacting Sound Tech (just within the warranty period) they told me they suspect it is a grey import and would not fix it for free. How can I tell if it is from the US or UK?
Can anyone help me here? I need to get it fixed (I'm in Somerset, UK)
The Amp doesn't respond to being switched on, no leds light, etc. The internal fuse is ok.
I tested the output of the rectifier that is putting out 300v DC... Is this normal?
Thanks in advance.
Posted 06 August 2013 - 07:10 AM
Posted 06 August 2013 - 07:30 AM
Posted 06 August 2013 - 12:01 PM
Posted 06 August 2013 - 12:18 PM
Are these the resistors that were/are part of the recall? Do you think this will fix the issue or could it have wiped out something else on the board?
I will go ahead and replace these ten resistors. Thanks again, I will post the result of my progress!.
Posted 08 August 2013 - 10:46 AM
If anyone can help me, I need
8x 47.8KΩ, 1 Watt, 1% resistors
2x 35.7KΩ, 1 Watt, 1% resistors
Thanks in advance
Posted 19 August 2013 - 11:16 AM
Posted 19 August 2013 - 11:18 AM
Posted 19 August 2013 - 12:14 PM
- Check 20A AC fuse; Make sure when cycled on, that 170V is available at the BULK voltage TP;
- If the SMPS has not fired, make sure that there is no shorted output or Tracker module devices; Verify that the chopper drivers are OK;
- Verify all the small SMT caps in the SMPS: I have found shorted C201, C186, for example.
- Verify the kickstart cap C196;
Posted 05 September 2013 - 08:43 AM
Posted 05 September 2013 - 09:14 AM
Though, I am quite surprised that the resistor replacement has not worked out.
NOTE: Reference in the SMPS is not chassis GROUND! Locate and use TP21 as your 0V [V_BULKRTN] reference.
Are the eight resistors are properly located in the SMPS section and the two other resistors in the output coil section?
Can you verify the signal at R375 in the SMPS section? (Normally, a 16V DC signal should be present.)
At the zener and R375 junction describe the signal there: Is it steady (around 1.5V)? Does it flucuate like a cap charging and discharging?
Posted 05 September 2013 - 11:02 AM
The voltage reading i get between the R375 junction and TP21 is steady at 6.3vdc?!?!
Posted 05 September 2013 - 11:46 AM
Note: If the cap was good, you would see a low voltage (perhaps 4 to 8V) pulsing signal at the R375 junction. Replace the cap with a 100uF/25V; I would try a 35V if available and I recommend the 105°C version (because of the heat generated by the resistors, though less problematic than the eight resistors in line of a previous version of the XTI!).
Posted 05 September 2013 - 12:40 PM