lowredmoon
Active Member
Greetings,
I've found a few threads here and there regarding the same issue I'm having with a C2A, but none that I've seen have been resolved. I'm starting this post with the hope that I can, with your help as well, resolve the issue and help others as well. I have a good DMM and an ESR meter. I'm trying to track down a power cord for my HP 141A oscilloscope, though I don't think this is much of a 'scoping issue.
I've preemptively ordered some 2SA1930 and 2SC5171 in case I need to replace the 2SA913 and 2SC1913 transistors.
Here are some details about the problem:
- The preamp plays fine, but is intermittently interrupted with a loud DC pop, followed by crackling and static noise. The sound then returns.
- It happens on both left and right channels, BUT NOT AT THE SAME TIME
- It occurs with any input selected
- Power supply voltage and idle current are stable. DC offset fluctuates, but only within about 25mV (the service manual specifies +/- 200mV).
Here's a video (I apologize to those who have to witness an NS-500 suffering this unfair torture).
I work a long and varied schedule, so there may be long gaps between posts, but I will post all progress here.
Thank you for chiming in!
Adam
I've found a few threads here and there regarding the same issue I'm having with a C2A, but none that I've seen have been resolved. I'm starting this post with the hope that I can, with your help as well, resolve the issue and help others as well. I have a good DMM and an ESR meter. I'm trying to track down a power cord for my HP 141A oscilloscope, though I don't think this is much of a 'scoping issue.
I've preemptively ordered some 2SA1930 and 2SC5171 in case I need to replace the 2SA913 and 2SC1913 transistors.
Here are some details about the problem:
- The preamp plays fine, but is intermittently interrupted with a loud DC pop, followed by crackling and static noise. The sound then returns.
- It happens on both left and right channels, BUT NOT AT THE SAME TIME
- It occurs with any input selected
- Power supply voltage and idle current are stable. DC offset fluctuates, but only within about 25mV (the service manual specifies +/- 200mV).
Here's a video (I apologize to those who have to witness an NS-500 suffering this unfair torture).
I work a long and varied schedule, so there may be long gaps between posts, but I will post all progress here.
Thank you for chiming in!
Adam
Last edited: