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I have a couple of PM 1400s and PM 950s that are slowly starting to stop working. One of my PM 1400s doesn't appear to power on (i'll have to check it again now that I know about the protection circuit). One of my PM-950s has clip protection going off on Channel 2 much earlier than Channel 1. I'm hoping to get either one or both repaired but given that I'm in a remote area of Hawaii, I may have to do it myself. I don't see much info available on these models, can anyone give me guidance on where to start? Are parts even available if I need them? mahalo nui loa

Greetings from Raleigh-Durham area. I repair vintage HiFi as a hobby. Few years ago I repaired a MXR-130 and loved the innovative technology used in the PS and FM stereo noise reduction design. Recently bought a Carver MXR-2000 that has loud hum in power transformer with -69vdc and +69vdc rails measuring at -/+99 volts on both. TRIAC was replaced with no change. All Zener diodes voltages ZD801 through ZD805 are normal. Appears that voltage monitoring circuit may be driving TRIAC to 100% duty cycle. I see design uses optocoupler to provide signal to control drive to the Q801 through Q804 to determine switch on/off time to the TRIAC to maintain the +/-69VDC. Is it safe to remove the TRIAC so I can power up rig to T/S the regulator circuitry? Thanks in advance for any suggestions. Mark

Carmen McRae, Just A Little Lovin'

First of all, Welcome to the Forum! Not sure of your electronics ability or even if you want to troubleshoot the gear yourself. Check in the document archive on this site for a service manual or schematics. If you cannot find them here, try Hifi Engine. If you dont have an account there, it can be problematic to obtain service data. Perhaps a Carver Site member can be helpful in that regard. I am speaking generically here, approach each device differently as they have different issues. Make no assumption of root cause. There is nobody on the internet that can say "Replace C10 and Q20" problem solved. Begin with some basic test equipment such as a multi meter. The PM1400 that wont power on, check the power supplies, rail voltages, etc. Step through logically, take copious notes and pictures. You can probably ship your device to the mainland if absolutely needed. Parts for vintage gear is always a question of availability. Capacitors can usually be substituted. Semiconductors, depending on what they are can be sub'ed as well. Semiconductors usually dont cause the main problem unless an amp has been abused, output shorted, etc, but its not out the question that the device failed. Be watchful for manufacture specific special purpose IC devices that are no longer produced. If special parts go bad, then you are on the hunt for a donor to pull the chips from. Sourcing replacement parts from Mouser.com can be useful. There are other suppliers as well, Google the device you want to replace. The best advice I can give, is to relax. Dont rush. Dont be impatient for a quick fix. If your amp recently failed, buy one that can play in your system while you fix the good stuff. At this point you may be thinking, "This guy is off the rails, nothing he said will get my "device" fixed". --- Welcome to the world of Vintage Gear! You will be fine. Use an approach of logic, troubleshooting, or sending out for repair. As Clint Eastwood would have said "A man's got to know his limitations"

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Aloha kakahiaka and Welcome to the Carver Site. In the manuals section of the site, you will find only one of the two service manuals that you are looking for. It will be the PM 1400, the 950 is not listed. Carver Manuals - TheCarversite!

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