working
From the picture and comparing with the service manual I concluded you removed all components connected to the internal opamps.
I gave it a try and it works indeed with external opamps of my choice, thanks!
I am still interested what you were using as IV.
Hi Lee,
From the picture and comparing with the service manual I concluded you removed all components connected to the internal opamps.
I gave it a try and it works indeed with external opamps of my choice, thanks!
I am still interested what you were using as IV.
IV
Hi Lee, Perhaps you can elaborate a bit about which type of IV-converter you were using.
Hi Lee, Perhaps you can elaborate a bit about which type of IV-converter you were using.
Hi. I can't find the schematic anywhere now.
I designed it myself and from what I remember it was based on this.
However, I'm sure I removed the filters from the inputs and placed one per channel on the output. I then used an extra single-fet buffer to drive the output.
Sorry I can't be of more help.
Lee.
.I designed it myself and from what I remember it was based on this.
However, I'm sure I removed the filters from the inputs and placed one per channel on the output. I then used an extra single-fet buffer to drive the output.
Sorry I can't be of more help.
Lee.
I have a problem with this player on the muting circuit but is not related to the 4 output transistors muting but something that acts on the 2114 ic.
Sometimes just turned on is fine for a few minutes ....... then the sound starts to crackle on both channels and the level drops until almost disappear
Can anyone explain the functioning and utility of the command "P-OFF" (I think that's giving me problems ....... C814 on LPS 5v?)
Thanks and sorry for my english.
Giuseppe.
at
Sometimes just turned on is fine for a few minutes ....... then the sound starts to crackle on both channels and the level drops until almost disappear
Can anyone explain the functioning and utility of the command "P-OFF" (I think that's giving me problems ....... C814 on LPS 5v?)
Thanks and sorry for my english.
Giuseppe.
at
I did fit a load of 100nF bypass caps - and I ran into a problem, which I thought had been caused by the addition of these caps, but I had splashed solder on the PCB - I only saw this *after* removing all the 100nF caps!!!
I never did refit them...
Thanks Tony ..... for all.
The service manual i need (first model KIS) is : 74CD17/92B
I bought two LME49990 to replace the 2414 (good choice?)
I go to replace (to test) the output capacitors with a 4.7 uF Mundorf Supreme (which I already have at home).
Unsure if change all capacitors considering the age of the player .......... fragile board can be a problem? ......... any advice to operate?
if I replace all capacitors with a good stuff I will not use bypass.
As soon as I have some money working on the clock.
The service manual i need (first model KIS) is : 74CD17/92B
I bought two LME49990 to replace the 2414 (good choice?)
I go to replace (to test) the output capacitors with a 4.7 uF Mundorf Supreme (which I already have at home).
Unsure if change all capacitors considering the age of the player .......... fragile board can be a problem? ......... any advice to operate?
if I replace all capacitors with a good stuff I will not use bypass.
As soon as I have some money working on the clock.
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I did reply to your PM - did you receive it?
I think you mean the NJM2114? in which case you need a dual opamp - the LME49990 is a single...
Also - there's little point to fitting fancy opamps unless you bypass the HDAM stage anyway.
I used some Wima caps in the output stage of mine. 2.2u IIRC.
The schematic I have shows the output caps as 2x 220uF in series - but my player had a single 100uF. So long as you're not trying to drive a very low impedance load, 2.2uF / 4.7uF will be fine anyway.
The capacitors on mine seemed fine when I checked them. It can only be a good move to replace the ones in the digital side with Oscons anyway.
The board wasn't too bad - but if you tweak it too much, I think it may be a problem.
Tanks .... received.
Yes sorry 2114 .... for LME49990 i have this adapters and 4 OP amp.
Yes HDAM will be bypassed.
Tanks for all your informations
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I would NOT bypass the HDAM in this player. It's completely different to the 63 HDAM which is a known weakness. Also as has already been stated, you don't need the DC blocking caps as there is no DC present on the output ( but check with a DVM on milli volts)
Definitely change the opamps and decouple with some nice caps like the new black Cerefine (same goes for HDAM decoupling caps)
DAC and other digital IC's want some solid polymer caps like OSCon SE type
Definitely change the opamps and decouple with some nice caps like the new black Cerefine (same goes for HDAM decoupling caps)
DAC and other digital IC's want some solid polymer caps like OSCon SE type
I don't call this "completely different" - apart from a few resistor value changes.
CD63 and CD17 HDAM schematic:
Attachments
I was very pleased in the past by the sound of TDA1547 with passive I/V and tube gainstage. (Grundig Fine arts CD3). Now I have a better idea how to realize it.
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