Hi guys !
Long story in short. Amp came in for a repair.
Hifonics Thor XI missing some parts:
resistor - RB12 + RA12 (both channel missing, both badly burnt PCD and traces)
cap - CP15
cap - CP17
Picture two (in the middle) is a picture I found in the web of the same amp, but it's so low in resolution i can't read the parts.
Voltage across terminals of CP15/17 is ~ 12v. So a cap V rated 16v or 25v would be sufficient, but what uf ?
RB12 + RA12 - don't know what they should be, but looks like 1W resistor ?😕
Long story in short. Amp came in for a repair.
Hifonics Thor XI missing some parts:
resistor - RB12 + RA12 (both channel missing, both badly burnt PCD and traces)
cap - CP15
cap - CP17
Picture two (in the middle) is a picture I found in the web of the same amp, but it's so low in resolution i can't read the parts.
Voltage across terminals of CP15/17 is ~ 12v. So a cap V rated 16v or 25v would be sufficient, but what uf ?
RB12 + RA12 - don't know what they should be, but looks like 1W resistor ?😕
Attachments
The resistors are 4.7 ohms.
Are the capacitors for the ±15v regulators? If so, they're not critical. Anything between 100 and 1000uf would likely be perfectly OK.
I'd connect a capacitor and measure the voltage to confirm that it's 12v. Noise can skew multimeter readings.
Are the capacitors for the ±15v regulators? If so, they're not critical. Anything between 100 and 1000uf would likely be perfectly OK.
I'd connect a capacitor and measure the voltage to confirm that it's 12v. Noise can skew multimeter readings.
Caps are connection between +/- rail voltage and the small amplifier board driving the output mosfets. (maybe VCC/Vref ?!)
Black probe on main GND of the amp, red probe - shows 35v at one of the pins of the cap and 47v at the other one. I don't remember which one was + and which one was -, but still 12v across the cap.
Black probe on main GND of the amp, red probe - shows 35v at one of the pins of the cap and 47v at the other one. I don't remember which one was + and which one was -, but still 12v across the cap.
Try anything in that range to see if there are any problems. If you have a scope that's isolated or in differential mode, monitor the voltage across the capacitor to see if it's significant.
Rails are -+ 35V...seems this amp has a regulated power supply as it doesn't change rail voltages almost at all in the b+ input 10v~15v. Looks like some kind of PWM switching power design.
Last edited:
Did you monitor the voltage across that cap when the amp was driving audio into a load to see if the voltage remained clean.
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)