Finally got my 50va tx from maplins,The legend on the side is a bit unclear primary 0-240=brown /blue sec1 0-12= red/yellow sec2 0-12= black/grey .thats as its printed on the tx am i safe to assume that blk/red are 0v and grey/yellow are +v.
cheers alan
So for a symmetrical supply for the servo
fh11 yellow= +12v
0v =red
fh12 black= +12v
0v = grey
thanks again alan
cheers alan
So for a symmetrical supply for the servo
fh11 yellow= +12v
0v =red
fh12 black= +12v
0v = grey
thanks again alan
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Al, I'm pretty sure that having 12v at both fh11 and fh12 isn't right.
See my previous post for details of my install
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1947.html#post3519179
See my previous post for details of my install
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1947.html#post3519179
Yes, this makes a big difference. Why the hell did they use ceramic for C505? Ceramic should not be used in the signal path.
Dos versus lme49720 opamps im interested in the comparison ? I like the sound i have @ the moment but itchy fingers and all that, We all know that one lol.
I don't have any experience with DOS but between 49720HA and discrete opamps I prefer the SQ from the discrete ones 🙂
I want to, Alan, but I still have to do more listening. It's not as simple as just that comparison because the whole output stage and power circuits were replaced. I spent a lot of time trying different op-amp power caps before settling on BG Ns, so those must've had an influence on the old sound, and they're out now. I had upgraded my filter caps with mica, but the resistors were still original. My stereo image is clearer now. There's so much to hear that is new and improved, but I'm sure there must be some trade off and I'm not sure what that is yet. I often A/B between CD and vinyl because I have several of the same albums in both formats. I think I need to do that with the DOS.
Oh yeah, also, established wisdom is that the DOS needs high quality regulators and big VA PSUs to sound its best. I just have four 7X12 regs fed by my existing supply (30VA?) with 22,000uF smoothers. Even as it is, it's definitely better on balance, both in terms of detail and musical enjoyment. I haven't had the hairs stand up on the back of my neck yet though.
One thing you can do if you have itchy fingers, Alan, is build one anyway and try it. It's possible to hook it up without removing the old output stage.
Cool pics! Those are two impressive looking players. One thing that jumps out to me about the discrete op-amp solution is that it looks like it must involve almost four times the component count of the DOS.
I found discrete Opamps sound better than metal CAN 49720HA but they need to have very low noise and stable voltage regulators to bring out their wonderful performances. I use +/- 15V to drive them.
Hi guys, my player is going wild and I can't seem to find the problem. When I switch it on the disk is spinning very fast and the sledge is going crazy. The display doesn't light up. Any idea's what it could be?
Before this I replaced c813 and c814 with a Pan FC 4700-25v so I can put in de new Tx later. Maybe something went wrong when I switch them.
tnks!
regards,
Bart
Before this I replaced c813 and c814 with a Pan FC 4700-25v so I can put in de new Tx later. Maybe something went wrong when I switch them.
tnks!
regards,
Bart
Check if the +/- of Caps C813 and 814 are correctly fitted. It seems you have lost the 5V supply to the circuits.