kikook said:Found them
Simonov :
I understand that I can remove them ?
Just some wiring in place of them, no more ?
Thanks.
They do not affect the sound in the same way as transistor muting so removal is not essential.
However, they do stop working.
So try tapping them gently while playing a cd or shorting them out to see if they are causing the loss of sound.
Andy
I've tried tapping them with no results.
Can I just add wiring between the different points of them without desolder them ?
Is there a method to test them in or out circuit ?
I've made some test with a tester while playing a cd :
Shot at 2007-07-12
Can I just add wiring between the different points of them without desolder them ?
Is there a method to test them in or out circuit ?
I've made some test with a tester while playing a cd :
An externally hosted image should be here but it was not working when we last tested it.
Shot at 2007-07-12
A few months ago I got a 104 with exactly the same problem.
In this case the output capacitors (22uF) were the cullprit.
The playing channel output capacitor was down to around 5uF.
The non-playing channel ouput capacitor was open.
The electrolytic capacitors dried out after so many years.
You might want to swap them for something else.
Anything of 22uF and similar size and minimum voltage rating
will be OK in this position.
According to the schematic in the servicemanual, the reference
designators for the capacitors are:
C2573 Left channel and C2608 on the Right channel.
The capacitors are situated on the decoder PCB in the vincinity
of the output opamps (NE5532)
I hope this helps.
In this case the output capacitors (22uF) were the cullprit.
The playing channel output capacitor was down to around 5uF.
The non-playing channel ouput capacitor was open.
The electrolytic capacitors dried out after so many years.
You might want to swap them for something else.
Anything of 22uF and similar size and minimum voltage rating
will be OK in this position.
According to the schematic in the servicemanual, the reference
designators for the capacitors are:
C2573 Left channel and C2608 on the Right channel.
The capacitors are situated on the decoder PCB in the vincinity
of the output opamps (NE5532)
I hope this helps.
Instead of bypassing the relays, you could/should consider
restoring them.
They are easely tested.
Take them out of the decoder pcb
Connect a multimeter, switch to resistance measurement.
Use a permanent magnet (old speaker or someting) to hover
above the relay assembly.
If the reedrelay is OK, the contact closes, and you will measure
a very low resistance, i.e 0 - 0.5 Ohms.
There are two reedrelays per assembly.
I think a grand old machine like a CD104 deserves restoration,
rather then a hack.
Knowing that your 104 will be like new, is a lot more satisfactory
than simply a music playing piece of hardware.
Offcourse, this is only an opinion.
Regards
kikook said:Thanks a lot !
Today, I will change the output capacitors and if I have no result I will try to bypass the relays..
I will give you the results here at once made !
I'm coming back in few hours
I think you're quite right
The best approach IMO is to have two 104's . One fully restored to its original brilliance and one modified, so that one could squeeze maximum performance Regards:
Venci
Hello,
about the output 'relay'. Yes they are reed switches, and I have successfully repaired them on other machines.
Often a little teasing with a large magnet (speaker voice coil or similar) will 'jog' them into life. This occurs if they have been idle for a few years (which is not uncommon for these old beasts).
If this does not work, or is reliable enough, then you can renovate the switch by replacing the reed switch themselves. The glass enclosed reed switches are available from most electronic stores, usually in the 'security' section, with the alarms.
anyway, just cut out plastic that holds the wires to the the glass enveloppe and straighten the leads, then slide out the old switch. Careful with the new switch, the glass envelope breaks easelly. Use two pliers to form the bend.
The new switches will be loose in the coil, as the plastic retainer has been cut, but this can be rectified by the soldering in on the board - the reed switch will remain in the correct place when soldered.
I fix 3 relays this way. still going - I'm listining to one as I write this.
An yes I agree, it's one of the 'classy' touches in those old players.
Philippe
about the output 'relay'. Yes they are reed switches, and I have successfully repaired them on other machines.
Often a little teasing with a large magnet (speaker voice coil or similar) will 'jog' them into life. This occurs if they have been idle for a few years (which is not uncommon for these old beasts).
If this does not work, or is reliable enough, then you can renovate the switch by replacing the reed switch themselves. The glass enclosed reed switches are available from most electronic stores, usually in the 'security' section, with the alarms.
anyway, just cut out plastic that holds the wires to the the glass enveloppe and straighten the leads, then slide out the old switch. Careful with the new switch, the glass envelope breaks easelly. Use two pliers to form the bend.
The new switches will be loose in the coil, as the plastic retainer has been cut, but this can be rectified by the soldering in on the board - the reed switch will remain in the correct place when soldered.
I fix 3 relays this way. still going - I'm listining to one as I write this.
An yes I agree, it's one of the 'classy' touches in those old players.
Philippe
Phimor, with your help and a speaker I have saved the relay on my first CD-104.
Thanks again !
So, now I have a working CD-104, I'm happy
In the other cd-104, the reed switches are definitely dead (broken), and when bypassing them, I have only sound on the left channel, right is out. But I have never seen this CD-104 working so....
I will make some tests on it but I can't exchange the boards inside to find the problem, because it's not the same boards (rev C and rev D)
Thanks again !
So, now I have a working CD-104, I'm happy
In the other cd-104, the reed switches are definitely dead (broken), and when bypassing them, I have only sound on the left channel, right is out. But I have never seen this CD-104 working so....
I will make some tests on it but I can't exchange the boards inside to find the problem, because it's not the same boards (rev C and rev D)
jives11 said:
I'm still oddly fascinated by the board layout of the decoder.
decoder board section
diode 6561(BAX18) delivers the +11.2v supply to the SAA70?0 chips, derived from the +12v supply for the output opamps and a 4.7K resistor (3550). there are local ceramic caps close to each chips 11.2v pin.
Q: Could diode 6561 be improved on ?. Digital and analogue supplies get joined at this point