Today my tube sockets arrived.
I actually quite like the old school look of it soft off white...matches great with the ebony and novar grip is better than the magnoval...more like a PiTbull.
(White ceramic magnoval next to it)
Lucky for me they are easily exchanged..so the ebony work was not for nothing...ready and mounted for rectification...the 6CL3 Sylvania
Awesome sauce !!
By the way, I managed to find a 10nF FT-1 Russian teflon cap. My setup is still quite messed up by the complete re-building after the problems I had, but an A/B test with the 12nF showed that the 10nF is significantly better with practically no effect in the reading ability. Both caps were removed from their metal casing and wood/wax treated. Oh and they still measure perfectly. C is exactly the same (before and after the mod) down to the tenth of a pico, and Q is steadily near zero.
By the way, I am currently using 220uF caps on most spots on the board and reading ability is much better. Crappy CDRs still skip a lot though and better ones still have the occasional click. Eventually I will change them all back to wood/wax treated 47uF for further testing. I also hope to receive extra transistors soon, so I will also check tibi's mod.
Oh and I am getting a second split bobin Hammond today, so I am expecting some serious upgrading from there too
By the way, I am currently using 220uF caps on most spots on the board and reading ability is much better. Crappy CDRs still skip a lot though and better ones still have the occasional click. Eventually I will change them all back to wood/wax treated 47uF for further testing. I also hope to receive extra transistors soon, so I will also check tibi's mod.
Oh and I am getting a second split bobin Hammond today, so I am expecting some serious upgrading from there too
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Good to see you active Dimitris in an otherwise amazingly quiet topic (quiet before a storm )
Anyway today I picked up ebony in order to make an ebony platform for my PiTbull Reference.
So far it was standing on a three ebony posts...I found that a bit unsafe (bumping against it) and the design could be a bit better.
I will make a heavy plateau out of birch lead and ebony..and I will implement a spirit level while I am at it.........if it sound like a turntable I might as well go " "dashing all the way".....
)Anyway today I picked up ebony in order to make an ebony platform for my PiTbull Reference.
So far it was standing on a three ebony posts...I found that a bit unsafe (bumping against it) and the design could be a bit better.
I will make a heavy plateau out of birch lead and ebony..and I will implement a spirit level while I am at it.........if it sound like a turntable I might as well go " "dashing all the way".....
I got no words Erik!!! Very nice !!!
On my end, I installed the second split bobbin Hammond on the motor side...
OK whoever is running that thing on toroids, you do not know what you are missing....
My setup is messed up, and I am still hearing new stuff on my favorite music after the change... clarity and textures are through the roof... I was a bit disappointed after my trouble, but after this I cannot wait to get it back on track...
On my end, I installed the second split bobbin Hammond on the motor side...
OK whoever is running that thing on toroids, you do not know what you are missing....
My setup is messed up, and I am still hearing new stuff on my favorite music after the change... clarity and textures are through the roof... I was a bit disappointed after my trouble, but after this I cannot wait to get it back on track...
OK, I spent a bit of time at it today. I think what is wrong is crap blank CDs!
I have been using a batch of cheap blank CDs of late, and when I went back and used shop-bought CDs theres no problem at all. When I look carefully at the blank ones while spinning you can see some runout on them. Other blank ones are fine, and they play OK. So the runout is magnified as you get to the outside edge of the DC and the mechanism has a hard time tracking it.
Alls ok in the world!!
Fran
I have been using a batch of cheap blank CDs of late, and when I went back and used shop-bought CDs theres no problem at all. When I look carefully at the blank ones while spinning you can see some runout on them. Other blank ones are fine, and they play OK. So the runout is magnified as you get to the outside edge of the DC and the mechanism has a hard time tracking it.
Alls ok in the world!!
Fran
Good to read that you solved it, such a problem can keep you quite busy...I remember having a bad laserribbon (too much handling with experimenting)...I made completely new boards before I tackled the problem.....
One modification to enhance CD-R, CD-RW and SACD reading.
Recently I got a SACD on which my Shiga refused to read TOC whatever I do.
I started to dig into problem and found one layout problem. This will be corrected in MKII.
C50 - 680pF and Q3 feed pin 59 - LF2 on LA9242. Quoted from datasheet:
"The mirrored surface level is maintained by the capacitor for LF2 (pin 59) ; when a drop in the EFM signal (RFSM
output) reaches 0.35V or more, a high signal is output to DEF (pin 49). If DEF (pin 49) goes high, the tracking
servo enters THLD mode. In order to prevent the tracking servo from entering THLD mode when a defect is
detected, prevent DEFECT from being output by either shorting DEF (pin 49) to GND, or shorting LF2 (pin 59) to
GND."
Therefore, even is not mentioned in any datasheet, C50 must be as close as possible to LC78601 pin - 47.
Q3 must be also as close as possible to C50 in order to avoid any spurious noise to get in.
C45 - 100 pF is there to reject any VHF noise on Q3 and must be as close to Q3 as well.
For me, moving C50 - 680pF and Q3 did the trick and now my unit read TOC without any problem even on the most dirty and old disks which are constantly rejected by a NAIM CD5 XS.
Please note that the pcb trace after LC78601 pin 47 must be cut as well, otherwise will act like a small antenna and this modification will have no effect.
Regards,
Tibi
I just tried this and unfortunately it did not solve my problem. CDRs are still almost unreadable or skip a lot, even good ones like freshly written Taiyo Yuden ones.
I give up...
Today I managed to finish the Shiga Tube Platform for my PiTbull Reference
No need for candles for christmas
Amazing...
Regards
Not really
I tried adding some more shielding here and there, and it seems that we got somewhat of a winner...
I added some sticky copper tape on top of both the chips including the in-between pcb space and finally there seem to be proper reading of CDRs. There's still the occasional click and tick-tick noise, but it's quite an improvement.