Hello,
I have an old used HCA-1000A Amplifier and a Parasound P/HP-850 Stereo Preamplifier. Both of them are from the USA, meaning 110V. I use a 220V to 110V transformer.
My problem is that there is no sound when everything is connected, I have tried all sorts of variations. Then I noticed that the amplifier is always in "AC Line" mode. I checked both the external and internal fuse, and all were healthy. Do you know where to look for the problem?
I have an old used HCA-1000A Amplifier and a Parasound P/HP-850 Stereo Preamplifier. Both of them are from the USA, meaning 110V. I use a 220V to 110V transformer.
My problem is that there is no sound when everything is connected, I have tried all sorts of variations. Then I noticed that the amplifier is always in "AC Line" mode. I checked both the external and internal fuse, and all were healthy. Do you know where to look for the problem?
Welcome to the forum!
You haven't provided much background information. Is this newly acquired equipment and your first attempt using?
I suggest when asking for forum help that you post user manual and service manual for best results. Since you're new to the forum, I'm attaching results from a couple of web searches. There may be more complete service manuals than what I stumbled across.
The owner's manual describes a procedure for manual starting the amp. Have you tried it? There's mention an external DC trigger for the power amp. Is this involved in any way?
Do you have any test equipment and experience with powered troubleshooting?
You haven't provided much background information. Is this newly acquired equipment and your first attempt using?
I suggest when asking for forum help that you post user manual and service manual for best results. Since you're new to the forum, I'm attaching results from a couple of web searches. There may be more complete service manuals than what I stumbled across.
The owner's manual describes a procedure for manual starting the amp. Have you tried it? There's mention an external DC trigger for the power amp. Is this involved in any way?
Do you have any test equipment and experience with powered troubleshooting?
Hello,
Thank you for your clarifications.
This equipment was used by my grandparents but has been out of use for about 10 years. I thought I'd pick it up. This is my first time trying it.
Yes, I tried to manually start the amplifier with the button but neither red nor green LED lights.
As I see it, the DC trigger is the function to turn on the amplifier without manually pressing the turn-on button. I think it's not mandatory.
I don't have any test equipment, just a set of screwdrivers and I don't have too much experience with powered troubleshooting.
I believe you're interpreting the DC trigger feature correctly.
This looks to be nice equipment. Do you want to attempt repair yourself? Any experience with electronics at all?
To do any troubleshooting will require a Digital Volt Meter, preferably with resolution of 0.1mV. You can get coaching from forum members, but very quickly you will probably need to desolder components and replace them. This implies soldering tools and associated skills. This looks like valuable equipment to cut your teeth with--- you'll be putting the amp at risk. So consider repair by a good shop vs. your background. Patience and a light touch are absolutely necessary.
All that said, if you want to pursue repair and have an interest in electronics, everyone starts at the beginning. Maybe we'll find something simple. I'll be suggesting tests with the unit under power; make sure you know how to troubleshoot safely!
It appears that that unit is powered whenever plugged in and that you have a lit LED is encouraging; we know that the simple power supply that powers the AC LINE LED is working. Cycling the POWER SWITCH should exercise relay RY1 and you should be able to hear it click and find DC across its coil. This should be the first step in fault isolation.