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Old 15th October 2011, 12:26 PM   #1251
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Quote:
Originally Posted by mogliaa View Post
Not at all, the Ll1660 use most of the space. Either way, I haven't built a complete separated chassis for LT and HT supplies. Salas regulator will be on the supply chassis
You have to modifie your Salas HV reg. for 4 wires Kelvin to avoid cable lenght.
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Old 15th October 2011, 12:41 PM   #1252
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Why? Will it gave a HF impact? Sure everyone would try to avoid long cables but if compensated properly should work fine?

May be able to squeeze the board on the preamplifier chassis but prefer not to.
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Old 15th October 2011, 02:36 PM   #1253
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Originally Posted by merlin el mago View Post
You have to modifie your Salas HV reg. for 4 wires Kelvin to avoid cable lenght.
Why? And how? Can you please explain?
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Old 15th October 2011, 05:29 PM   #1254
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Wikipedia information about 4 wire Kelvin

Four-terminal sensing - Wikipedia, the free encyclopedia
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Old 16th October 2011, 04:09 PM   #1255
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Salas shunt regulator board completed today. Tested and works nicely. Set output voltage about 170V with input of 200V. Ripple is below 10mV but probably is picked up by my oscilloscope leads in my noise workbench.

Now back to metal work and get the supply chassis done!
Attached Images
File Type: jpg SALAS HT shunt reg for 26 preamp.jpg (77.1 KB, 525 views)
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Old 16th October 2011, 05:12 PM   #1256
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Schematic four wires Kelvin for remote sense, link:

Simplistic Mosfet HV Shunt Regs

Click the image to open in full size.

Last edited by merlin el mago; 16th October 2011 at 05:17 PM.
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Old 16th October 2011, 05:32 PM   #1257
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Tested today with a 50cm leads and couldn't see the difference in voltage drop/ripple. The shunt regulates fine, so will go with the original circuit. Also don't have space left in the chassis, so will be placed on the supply chassis. Will build as is and report results (hopefully soon)
cheers,
Ale
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Old 16th October 2011, 05:34 PM   #1258
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If you use long wires is better if you use four wires Kelvin connection.
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Old 16th October 2011, 09:38 PM   #1259
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Originally Posted by FRUGIVO View Post
this is my project now
source-DAC pcm58- nos--resistor- i/v converter
gain-#27
driver-#26
output-6c33 1w SE OTL cathode follower
Speaker Lowther EX4 in Hedlund horn
Click the image to open in full size.
Click the image to open in full size.
Que bello amplificador (what a beauty)!
I would love to see a schematic - can you post one?
Muchas gracias,

-- josť k.
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Old 18th October 2011, 08:06 AM   #1260
regal is offline regal  United States
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Originally Posted by mogliaa View Post
Salas shunt regulator board completed today. Tested and works nicely. Set output voltage about 170V with input of 200V. Ripple is below 10mV but probably is picked up by my oscilloscope leads in my noise workbench.

Now back to metal work and get the supply chassis done!
I would say with 10mV ripple it is probably oscillating, what is the ripple going in after the prefilter ?
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