• Content count

  • Joined

  • Last visited

Community Reputation

0 Neutral

About e_c_mccollum

  1. Goes out when signal is applied and comes back on when signal is gone. Odep circuit malfuntioning? Odep not biased properly?
  2. Got a macrotech 2400 with an odep issue. The odep lights are bright when powering up with no signal. With signal applied, amp in stereo mode, ch. 2 odep light goes out. Going to clean amp out and check for soldering. Any other ideas? Speakers ,cables, and inputs are good.
  3. Found ODEP circuit to be messed up to. Need replacement for the dual transistors 2sc3381 and 2sa1349. There apparently hard to find.
  4. Amp now has intermittent problem with distortion on ch.1 output. Voltage across R02 jumps from spec. to zero and back again. Voltage across R21 is spec. VCC is +/- 61 volts at idle. Did find the 3W 2.7ohm resistor on output shorted. Going to replace predrivers and current limiting trans.
  5. Got amp running again. Checked and resoldered c07, c06. Problem went away. Circuit board and components looked good.
  6. Bias transistor was'nt shorted. When switched the two bias transistors around to see if the problem went to channel 2, both channels worked great. Replaced both to be sure. Worked perfectly afterwards. Could be a bad connection on the board of channel one. Will look into checking resistors and current limiters. When I got amp back, it showed up with a big dent on bottom. More work to investigate.
  7. Got a 2400 in with severe distortion on output. It was used in parallel mode at two ohms. Swicthed it to stereo and discovered ch. 1 distorted, while ch. 2 sounds fine. Futher investigation on ch. 1 revealed low side bias voltage was spec. while high side was zero. Replaced the bias transistor fixing the problem on high side. Returned amp, hooked it up in parallel mode like before and distortion came back. Looking for other weak parts on ch.1. Any help would be great. Odeps Leds on front where bright.