Hi,
New to this forum. Not sure if this is the right thread, hope anyone can help.
My Marantz PM7200 has had an issue that was quite insignificant but has grown over time. After powering up (always from stand by) the right channel doesn't have any sound. When I increase the volume, the right channel suddenly pops in. Same case with Headphones. At first this problem only showed when using Tape In as source (attached to my PC) but later also on other inputs like Phono or CD.
I'm pretty sure the problem is in the pre-amp and I would like to check the pre-amp board for any possible faulty connections. However, it turns out to be a nightmare to disassemble the Marantz in order to reach the pre-amp board. Can anyone provide me with instructions how to reach the pre-amp board without having to take the amp completely apart?
Thanks for any help! Mike
New to this forum. Not sure if this is the right thread, hope anyone can help.
My Marantz PM7200 has had an issue that was quite insignificant but has grown over time. After powering up (always from stand by) the right channel doesn't have any sound. When I increase the volume, the right channel suddenly pops in. Same case with Headphones. At first this problem only showed when using Tape In as source (attached to my PC) but later also on other inputs like Phono or CD.
I'm pretty sure the problem is in the pre-amp and I would like to check the pre-amp board for any possible faulty connections. However, it turns out to be a nightmare to disassemble the Marantz in order to reach the pre-amp board. Can anyone provide me with instructions how to reach the pre-amp board without having to take the amp completely apart?
Thanks for any help! Mike
Probably one of the relays needs to be replaced. Try tapping each relay with a wooden stick and see if the right channel pops in.
Mike,
first get yourself a good copy of the service manual or schematic then you can start properly troubleshoot.
Do not take anything apart yet.
first get yourself a good copy of the service manual or schematic then you can start properly troubleshoot.
Do not take anything apart yet.
Marantz sets were way too complicated.
Search for that model, see threads here and on other forums too.
Then take photos at each stage.
Some were so unusual that fixing them was a nightmare.
Like a cranky race car, you set one thing and something else goes haywire.
Try getting a chip amp, or another make from private sales, to listen.
This may take time to fix.
Search for that model, see threads here and on other forums too.
Then take photos at each stage.
Some were so unusual that fixing them was a nightmare.
Like a cranky race car, you set one thing and something else goes haywire.
Try getting a chip amp, or another make from private sales, to listen.
This may take time to fix.
Probably not; the relais doesn't change anything when tapping. After tapping the pre-amp board and using some contact spray on the Tone Direct and Class A switches the problem is much smaller, though. Still present, but only for a second after switching on. Sounds like a bad contact to me, somewhere.
I have a copy of the service manual, but I'm a novice in that area. I wouldn't dare take anything apart yet.
I was already thinking in that direction. Taking the amp apart just to have a look at the pre-amp board would indeed be a nightmare. For me, that is.
Sounds like a contact issue. Try exercising all switches and pots 40 times and see if it helps.
If it takes a second now, could be a weak capacitor, which may reform if the unit was in storage.
Use it for a week or so, an hour or so daily.
Tell us about it after a week.
Use it for a week or so, an hour or so daily.
Tell us about it after a week.
Thanks for your reply. Unfortunately the problem went back to its original stage. The amp hasn't been in storage and has been used pretty much on a daily bases. A bad capacitor could very well be the case. In order to see or replace a capacitor however, I have to take the whole amp apart because the (pre-amp) boards can't be reached.
You sprayed all the contacts in the selector, pots and so on?
The with the cover off, use a plastic rod (ball pen!), and tap the incoming terminals and relays with the set working..
Plastic is an insulator.
DO NOT use a metal probe!
Could be a stupid dry joint.
If you do have to open the set, change all the electrolytic capacitors.
At least at one effort, you are assured such a fault will not occur for some years.
The with the cover off, use a plastic rod (ball pen!), and tap the incoming terminals and relays with the set working..
Plastic is an insulator.
DO NOT use a metal probe!
Could be a stupid dry joint.
If you do have to open the set, change all the electrolytic capacitors.
At least at one effort, you are assured such a fault will not occur for some years.
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