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Old 1st February 2012, 11:28 PM   #101
bcmbob is online now bcmbob  United States
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The soft-start is working beautifully. Power present and active leds as well as MyRef lights all on. Woopeee!

20120201_191227.jpg

20120201_191251.jpg

Next I will test powering both the Lighter Note and the JC-2 from the 18V toroid. Might even be able to eliminate a transformer rather than adding one. I'll still isolate all the toroids with fuses but may not need the additional relays. ?????
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Old 2nd February 2012, 12:41 PM   #102
bcmbob is online now bcmbob  United States
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Latest wiring diagram with LN and JC-2 on same transformer. Total VA is now 450 which I believe can be handled by the soft-start alone. If anyone thinks more still needs to added, please post your comments.

Power Sch V2a.jpg
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Old 2nd February 2012, 03:33 PM   #103
AndrewT is online now AndrewT  Scotland
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The 50VA should also be fused.
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Old 2nd February 2012, 07:07 PM   #104
bcmbob is online now bcmbob  United States
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Hi Andrew,

Fuse added. Do you agree no additional timing elements need to be added? I want to incorporate as few components as possible but don't want to omit anything essential.

Also, with the SS mounted outside the shield, its transformer is close to the JC-2. It can be located inside the can if that is recommended to avoid interference. Manufacturer (BingZi) docs just say fully encapsulated but no mention of shielding.
Power Sch V2a.jpg
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Old 3rd February 2012, 12:13 AM   #105
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Quote:
Originally Posted by bcmbob View Post
Do you agree no additional timing elements need to be added?
As long as the limiting resistors in your softstart can handle the initial surge of your two large toroids and the relay contacts in your softstart can handle the "steady on" current for those toroids, you're "good to go". .....Should not be any problems......

One possible failure mode (and I'll admit, I haven't had time to study your schematics.....): If the softstart fuse pops, and your softstart does not operate, will this place the limiting resistors in series with their toroids until you turn power off to the unit? If so, they may overheat...... This is probably a pretty remote failure mode--if it is, in fact, what your schematic shows.
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Old 3rd February 2012, 09:13 AM   #106
AndrewT is online now AndrewT  Scotland
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If the soft start fuse blows, then PIN of J1 is isolated. No current flows through any internal transformers.
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Old 3rd February 2012, 01:14 PM   #107
bcmbob is online now bcmbob  United States
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Great, I think it's all here except a couple fuse holders to get from Radio Shack. I'll be putting it all together in the next couple days. The assistance and information has been nothing less than fantastic and I express my gratitude to all.

As Arnold would say - I'll be back
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Old 5th February 2012, 10:55 PM   #108
bcmbob is online now bcmbob  United States
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Had everything connected in the chassis but found the small toroid was overheating. The only thing found were a couple loose solder joints on the MyRef AC input tabs. Don't know if that was part of the problem.
Went back to modular approach (adding one component at a time) and everything is now stable at just above room temps.

I also had the power switch on the hot wire after the soft-start (with pin 1 & 2 on J2 jumpered) which kept the SS always on. I am revising to use the switch to activate the SS from J2 and that will leave it in standby with only the "power present" LED lit. My Denon receiver has two power switches - main and user - but I don't think that will be necessary here.

20120205_172828.jpg

20120205_172807.jpg
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Last edited by bcmbob; 5th February 2012 at 11:01 PM.
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Old 11th February 2012, 03:15 PM   #109
bcmbob is online now bcmbob  United States
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Default Up and sounding fine - kind -of.

Up and sounding fine - kind -of.

The AC wiring is functional and stable. The sound is clear, clean with not a trace of hum. Somewhere in my maneuvers I messed up the Lighter Note to where I cannot get one of the proper calibration readings. I suspect that will be solved easily by replacing one or a pair of the LDRs in the left channel. Uriah will let me know.

In the meantime I am auditioning this pot recommended by a forum member.

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The pot allows full volume at about 11:00 o'clock (~ 40%) rotation. There is just a minor dimple of a click as the wiper crosses over the staggered gold plates inside - not really a problem.
Intf 02.jpg

The signal after the pre passes through Neotech solid core wire. I didn't order quite enough of the smaller size to get the lengths and placement that I want so I will buy some more before final assembly. For now, I'm using silver plated stranded copper wire from ApexJr for all the other connections.

Intf 03.jpg

As I said earlier, the front panel switch now activates the soft-start through the J2 block via the small cat-6 white and green wires. That allows the mains power to be available just up to the in of the SS til J2 is shorted.
Intf 04.jpg

IntF 04a.jpg

The power leads for the LN are still in place.
Intf 05.jpg

Just for kicks, I am also going to audition the Lightspeed as the driver for the preamp. My general impression after a couple days is that I will prefer the adjustment capabilities of the LN to tailor the sound to my personal preferences - as described in the LN documentation. The mechanical pot does a great job with clarity, definition and volume control in this setup, but I think I'm missing some airiness and separation when comparred to the LN.
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Old 11th February 2012, 03:25 PM   #110
PJN is offline PJN  United States
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Nice Job Bob !

PJN
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