marcusdeming said:
Then it's time to move on to Brent's list. Tell us what's not good about the sound and we can tell you what to upgrade.
Malefoda said:
Anyone using this as their main source needs a serious clock and serious psu. Anything less is a false economy.
Chivvyp said:
But he already bought an amp!
Simon
marantz 67 mod
Hi guys, i replace all diode with Hexfred, follow the mod list as per Ray pdf but the left chanel has no sound, at CF01-i used inductor from Jaycar- 150mH/4.2R whereas all other position are 470mH/2.5R-would this cause theproblem?
or should i undo all the soldering and start again? Any hints would be appreciated. Thanks. Quan
Hi guys, i replace all diode with Hexfred, follow the mod list as per Ray pdf but the left chanel has no sound, at CF01-i used inductor from Jaycar- 150mH/4.2R whereas all other position are 470mH/2.5R-would this cause theproblem?
or should i undo all the soldering and start again? Any hints would be appreciated. Thanks. Quan
Re: marantz 67 mod
Does the other channel sound ok? Is there any DC on the output or anything suspicious like that on either channel?
If one side works but the other doesn't it's probably quite a simple problem to solve (relatively). If you can touch a wire (connected to the interconnect feeding your amp) to the output pin of the op-amp, whilst music is playing, you will eliminate some parts of the circtuit from blame. If you hear the music then you must have an open circuit somewhere between the op-amp and the output socket. This should be easy to fix.
If you get no joy from this it's probably an op-amp leg not soldered in properly. Check the op-amp power supply pins for voltage (+12v and -12v: i think it's pins 4 and 8 but please check).
Simon
quan said:
Does the other channel sound ok? Is there any DC on the output or anything suspicious like that on either channel?
If one side works but the other doesn't it's probably quite a simple problem to solve (relatively). If you can touch a wire (connected to the interconnect feeding your amp) to the output pin of the op-amp, whilst music is playing, you will eliminate some parts of the circtuit from blame. If you hear the music then you must have an open circuit somewhere between the op-amp and the output socket. This should be easy to fix.
If you get no joy from this it's probably an op-amp leg not soldered in properly. Check the op-amp power supply pins for voltage (+12v and -12v: i think it's pins 4 and 8 but please check).
Simon
quan said:
To measure DC you put your multimeter black on the ground of the output socket and red into the middle. Set your meter to read DC volts, turn the player on and read off the figure. If it reads in whole volts rather than millivolts you have a problem. But this does also completely depend on whether or not you removed the DC blocking caps!
I believe you need pin 7 for output of the op-amp. Whatever you do don't short it out to pin 8. There will be a resistor or wire link that you can take this signal from, to avoid risking shorting anything on the op-amp itself. Can anyone help us here by remembering what resistor that is?
If the digital output is ok your problem should be easy enough to fix. (says he who pulls his hair out for days and weeks when it stops working...)
Simon
Re: marantz 67 mods
I would suggest the right opamp is missing its -12V if there is +12v on the output (or vice versa).
Brent
quan said:Hi Simon, the right chanel showed 12V- ?analogue circuit problem -How do i trace the problem? Just another question ,how soon can i start working on cd player after switch off?you know those nasty shock?no chance taken. Quan.
I would suggest the right opamp is missing its -12V if there is +12v on the output (or vice versa).
Brent
marantz 67 mod
Thanks Brent/Simon-it's kind of getting late down under-i will definitely check the right op-amp socket solder pad tomorrow and will let you guys know it goes. This is my first diy kind of stuff-it is addictive-although +++head ache, and iam waiting for Marantz 63 delivery in the next day or two as the next project. Quan
Thanks Brent/Simon-it's kind of getting late down under-i will definitely check the right op-amp socket solder pad tomorrow and will let you guys know it goes. This is my first diy kind of stuff-it is addictive-although +++head ache, and iam waiting for Marantz 63 delivery in the next day or two as the next project. Quan
rowemeister said:Lets hope notor if so lets hope the opamp is ok.
Brent
I wonder if the headphone amp is still in circuit in this player?
If the 12V is getting into the output of the filter op-amp via a short, the h/p amp input coupling caps will stop it getting to the h/p op-amp and thus the jack.
If the -12V supply is not there, there will probably be massive offset on the h/p jack too as they run off the same supply.
Might reveal something. Don't plug phones in though, 12V won't do them any good.
aquar said:
Hi Aquar,
Could be something's wrong with your wiring, since the reg works o.k. before fitting. Like Andy says, check the wiring and solder joints.
Second option could be there's something wrong with the transistor and cap-multiplier at the input of the LM317. If the transistor somehow doesn't get enough base current, the voltage will drop. Check the voltage at the input of the 317, it should be >14V.
Ray