Trodder
Member
It seems a lot of these heavily electronic turntables are really starting to reach a period of issues and failure. If you are lucky you realize a lot of the issues are resolved by simply recapping the turntable BEFORE it causes a chip (microprocessor) failure. Right now I have a Denon DP-51F that is exhibiting some slightly erratic tracking force issues. As this is a purely electronic function, I have to go after electronic components to resolve it. I first tried to make the VR adjustments per the service manual but getting a constant value there is not possible. The voltage read out is very erratic and I suspect it should be a little more static.
Initial Symptom Exhibited: While playing a record, out of nowhere, the sound started degrading and then I suddenly watched the tone arm start drifting away from the disc (record). After that I could not get it to sit back on the arm rest without turning the turntable off and back on again. I could usually get things to work again for a very short period time. If I started moving the tracking adjustment or q damping dial I would get inconsistent and erratic behavior there as well. I eventually took the cover off the bottom to go through the VR adjustments and found that if I tune it to say exactly 2g of tracking force, it would slowly deprecate for a bit and then just essentially fail. Then if I attempted to use the tracking force dial instead of the VR adjustment, it would give me just as an erratic tracking force as the VR did.
Based on my research it appears that most of the issues these old Denon's, JVC's, etc are fixed by simply recapping. Most of the symptoms vary across the board from tone arms slamming against their stop points, to lead in and lead out points constantly changing. Or in my case, tracking force not remaining consistent. Some cases do unfortunately result in a microprocessor failure, but that is usually a result of caps going unreplaced for too long and then a more catastrophic failure occurs.
Now I know everyone has an option on recap all or just what is needed. However, we have to get real about the fact that much of this stuff is simply reaching end of life and a proactive approach isn't necessarily a bad one. If your skill level enables you to test and troubleshoot your way to replacing just a couple caps, more power to you. However, for the rest of us, we can solder like nobodies business, but being able to T/S to narrow down issues to a single or maybe a couple components may not be possible or is so incredibly time consuming, they cant afford to keep going through this as each component starts to fail. So... here we are. I am going to attempt some risk mitigation and swap most if not all capacitors in this turntable in hopes of preventing a microprocessor failure that may cause me to have to scrap the table.
Here is the list I developed from the Service Manual. Hopefully that helps others? Please let me know if you cant see it.
Denon DP-51F Capacitor List - Click Here
Here is where I need all of you help!!
My first question for the group is... should I bother replacing the ceramics? If so, should I replace them with like for like or try squeezing in electrolytic or maybe even film caps?
Should I replace all electrolytic with film? Is it worth it?
Do I need to care about any spec other than capacitance and voltage?
When should I consider a larger value cap for capacitance?
When should I consider or should I even consider "audio grade" caps for a turntable?
Any brand caps I should stay away from?
Any easy way to use my cap list to create a parts list on an online retailer like what Mouser does with their BOMs? It seems none of the part numbers I have are relevant in Mouser. So not sure if there is a place that can give you functional equivalents or anything by loading a list of these old parts?
Lastly, I will attach a copy of the service manual here that is better than what is in the AK database if I find it is allowed to add here. I need to go look at the rules again to make sure. Although it might be too large to post here. So if I can find a place to host it, I can just put it there and link it.
Any other advice or tips is welcome!!
Initial Symptom Exhibited: While playing a record, out of nowhere, the sound started degrading and then I suddenly watched the tone arm start drifting away from the disc (record). After that I could not get it to sit back on the arm rest without turning the turntable off and back on again. I could usually get things to work again for a very short period time. If I started moving the tracking adjustment or q damping dial I would get inconsistent and erratic behavior there as well. I eventually took the cover off the bottom to go through the VR adjustments and found that if I tune it to say exactly 2g of tracking force, it would slowly deprecate for a bit and then just essentially fail. Then if I attempted to use the tracking force dial instead of the VR adjustment, it would give me just as an erratic tracking force as the VR did.
Based on my research it appears that most of the issues these old Denon's, JVC's, etc are fixed by simply recapping. Most of the symptoms vary across the board from tone arms slamming against their stop points, to lead in and lead out points constantly changing. Or in my case, tracking force not remaining consistent. Some cases do unfortunately result in a microprocessor failure, but that is usually a result of caps going unreplaced for too long and then a more catastrophic failure occurs.
Now I know everyone has an option on recap all or just what is needed. However, we have to get real about the fact that much of this stuff is simply reaching end of life and a proactive approach isn't necessarily a bad one. If your skill level enables you to test and troubleshoot your way to replacing just a couple caps, more power to you. However, for the rest of us, we can solder like nobodies business, but being able to T/S to narrow down issues to a single or maybe a couple components may not be possible or is so incredibly time consuming, they cant afford to keep going through this as each component starts to fail. So... here we are. I am going to attempt some risk mitigation and swap most if not all capacitors in this turntable in hopes of preventing a microprocessor failure that may cause me to have to scrap the table.
Here is the list I developed from the Service Manual. Hopefully that helps others? Please let me know if you cant see it.
Denon DP-51F Capacitor List - Click Here
Here is where I need all of you help!!
My first question for the group is... should I bother replacing the ceramics? If so, should I replace them with like for like or try squeezing in electrolytic or maybe even film caps?
Should I replace all electrolytic with film? Is it worth it?
Do I need to care about any spec other than capacitance and voltage?
When should I consider a larger value cap for capacitance?
When should I consider or should I even consider "audio grade" caps for a turntable?
Any brand caps I should stay away from?
Any easy way to use my cap list to create a parts list on an online retailer like what Mouser does with their BOMs? It seems none of the part numbers I have are relevant in Mouser. So not sure if there is a place that can give you functional equivalents or anything by loading a list of these old parts?
Lastly, I will attach a copy of the service manual here that is better than what is in the AK database if I find it is allowed to add here. I need to go look at the rules again to make sure. Although it might be too large to post here. So if I can find a place to host it, I can just put it there and link it.
Any other advice or tips is welcome!!
