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Re: First 12 series build
Posted: Thu Dec 25, 2014 3:10 am
by Lbrown3743
Measured it. Exactually like you said. Thing is coming along. Decided to fuse the live wire instead of the neutral.
Im using the larry ground setup so should i install a buss wire on the back of the pots?
Re: First 12 series build
Posted: Thu Dec 25, 2014 12:15 pm
by vh junkie
On the OT secondaries, just to be sure you can leave both wires long enough to reach v6 pin3. That way if you have to swap them later the one going to v5 pin3 will be long enough. With the ****** trannies you probably will not have to swap them later, but it is good to have enough wire in case.
I would not use buss wire or ground the any pot legs to the back of the pots when using the Larry ground. Just connect the ground wire the appropriate pot lugs. The pot bodies will get grounded/shielded via their mechanical attachment to the chassis. This makes it easier to swap in/out different pot values/types... also avoids ground loops.
Re: First 12 series build
Posted: Thu Dec 25, 2014 11:28 pm
by Lbrown3743
What happens when the wires are swapped?
Re: First 12 series build
Posted: Fri Dec 26, 2014 8:43 am
by neikeel
Lbrown3743 wrote:What happens when the wires are swapped?
Bad noise
Re: First 12 series build
Posted: Sat Dec 27, 2014 9:30 pm
by Lbrown3743
Re: First 12 series build
Posted: Sun Dec 28, 2014 7:47 am
by neikeel
Looking good so far, I would suggest you shorten those long loopy black wires to your preamp heaters, that is all
Re: First 12 series build
Posted: Sun Dec 28, 2014 8:55 am
by vh junkie
... and I would consider separating the OT primaries and secondaries. Look like you could leave the primaries running between v5 and v6; but, move the secondaries so they run between v6 and v7...
Re: First 12 series build
Posted: Sun Dec 28, 2014 11:11 pm
by Lbrown3743
im going to try and seperate the OT primary and secondaries a little. Hopefully get this beast fired up this week.
Re: First 12 series build
Posted: Tue Dec 30, 2014 6:58 pm
by Lbrown3743
confirmed from Chris M E R R E N this morning
T2562 PT WIRING
PRIMARY:
ORANGE = NEUTRAL
WHITE/RED STRIPE = 100 V
RED = 120 V
BROWN = 220 V
BLUE = 230 V
PURPLE - 240 V
SECONDARY
THICK BLACK = 6.3 V HEATERS
THICK GREEN = HEATER CENTER TAP
BLACK AND BLUE WIRES = 465 V GOES TO STAND-BY OR DIODES
BLACK/YELLOW AND BLUE/YELLOW = 500 V SAME AS ABOVE
YELLOW = HIGH VOLTAGE CENTER TAP
WHITE = BIAS
GREEN = BIAS GROUND
C1998 100 WATT OT
PRIMARY:
RED = V4 & V5 PLATE PIN #3
WHITE = CENTER TAP B+
BROWN = V6 & V7 PLATE PIN #3
SECONDARY:
BROWN = GROUND
BLACK = 4 OHMS
YELLOW = 8 OHMS
GREEN = 16 OHMS.
so looks like I got everything hooked up right. Time to finish it up.
Re: First 12 series build
Posted: Wed Dec 31, 2014 4:42 am
by Lbrown3743
Got everything together. Heaters are working but when i flip the stand by to on the mains fuse blows. So far have not found anything wrong connection wise. Any suggestions?
Re: First 12 series build
Posted: Wed Dec 31, 2014 5:54 am
by neikeel
First off is it a SLO BLO fuse of the correct rating (I know it sounds daft, but.....)
If it is your mains fuse that goes it would suggest an HT issue before the HT fuse (common mistake can occur on rectifier wiring or diode arrangement) check and double check your diode alignment.
So with standby off tell us your ac HT readings (outers and centre tap, heater numbers and bias feed) pos these back before blowing more fuses.
How have you wired standby (DPST with ac HT to switch like later amps or in rectified HT line)?
Re: First 12 series build
Posted: Wed Dec 31, 2014 10:11 am
by Lbrown3743
Just saw the ball drop in tokyo. Need to get home to get the beast working.
Re: First 12 series build
Posted: Wed Dec 31, 2014 1:02 pm
by Strat78
pics would be good at this point. Happy New Year!
Re: First 12 series build
Posted: Wed Dec 31, 2014 8:42 pm
by Lbrown3743
Re: First 12 series build
Posted: Wed Dec 31, 2014 9:34 pm
by Lbrown3743
The fuses are the correct rating. Im getting all the correct voltages. Im getting 97 from the wall. 2.9 on the heaters. 171 on each secondary at the switch and 98 on the bias. Something on the power board is wired wrong but i havent figured it out yet. The diodes look like they are right.
