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Old 31st December 2011, 04:37 PM   #1481
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Just finished purchasing Rod's regulator boards.

I believe I will use some regulator VR tubes for my HV B+. Looking at Coolzero's power supply diagram it shows he used a CCS before his regulator tubes.

Suggestions would be appreciated for the CCS as I have zero experience here.
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Old 31st December 2011, 04:52 PM   #1482
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HV CCS is fairly easy to build using IXYS 10M45 and Supertex DN2540 in cascode.

Just using another DN2540 instead of the parallel 10M45 will be fine in case of the 6 to 10mA #26 circuit.

Example circuit:

Cascode CCS idea

The unlabelled resistor network takes values according to the current you need, from the curves in the DN2540 datasheet, or from other's suggestions, eg:

DN2540

IXYS and Supertex parts are available at Mouser.
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Old 31st December 2011, 04:56 PM   #1483
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Rod,

Do you have a board available for this?
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Old 31st December 2011, 06:36 PM   #1484
mogliaa is offline mogliaa  United Kingdom
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This simple gyrator performs beautifully. I tested it with 4P1L, 01a, 30, 46, 112a and 26. Better performance and sound if connected as mu follower

4P1L DHT Line Stage

Happy new year to all!
Cheers,
Ale
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Old 31st December 2011, 06:40 PM   #1485
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Quote:
Originally Posted by Original Burnedfingers View Post
Rod,

Do you have a board available for this?
You could contact K & K Audio - Lundahl Transformers, audio DIY kits and more for kits
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Old 31st December 2011, 07:20 PM   #1486
iko is offline iko  Canada
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Quote:
Originally Posted by mogliaa View Post
This simple gyrator performs beautifully. I tested it with 4P1L, 01a, 30, 46, 112a and 26. Better performance and sound if connected as mu follower

4P1L DHT Line Stage

Happy new year to all!
Cheers,
Ale
Better than using the choke or output/it transformer?

Happy new year chaps!
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Old 1st January 2012, 10:48 AM   #1487
mogliaa is offline mogliaa  United Kingdom
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In my opinion I do prefer the OT (LL1660 and filament bias). However, the mu-follower gyrator is very close to it.
Haven't done yet a side by side comparison 26 OT against gyrator version which I will do in the near future.

Ps: I'm still trying to recover from last night!
Cheers,
Ale
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Old 1st January 2012, 04:33 PM   #1488
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Ok, trying to make a CCS plate load

Could you please tell me if I'm on the right track?

2) DN2540's
Attached Images
File Type: jpg CCS.jpg (71.5 KB, 566 views)
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Old 1st January 2012, 09:29 PM   #1489
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Joe, CCS circuit looks OK with DN2540

1K gate stoppers can be 220 Ohm to 1K or so.
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Old 2nd January 2012, 11:21 AM   #1490
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I'm going to post my power supply and my line stage chassis schematic in the hope that you guys in the know will look at it and tell me if I'm on the right track to start working on it.

The power supplies will be dual chassis dual supplies and the line stages will also be dual chassis. My reasoning is this... I would like to construct something without any cross talk and or noise.

The power transformers are an ebay purchase $20 Ea plus shipping. These will recitfy at 335VDC with #80 rectifier. They have no center tap so I added diodes also.

The filament transformers I purchased 30 yrs ago and I have about $12 in each of them. I have some mega 1500/450vdc 525vdc surge (Mallory)

I like the look of VR tubes so I incorporated (2) of them also.

The CCS plate supply is to be made up of two cascoded DN2540's. Schematic is on a prior post. Had sent an email to K&K Audio in the hope of purchasing two printed circuit boards with parts and heat sink. Received an email stating that they no longer use the DN2540 and the IXYS sounds better. See post 1488 for CCS plate supply. Added CCS to attached files.
Attached Images
File Type: jpg #26 line stage chassis.jpg (121.1 KB, 514 views)
File Type: jpg #26 line stage power supply.jpg (120.2 KB, 485 views)
File Type: jpg CCS.jpg (71.5 KB, 466 views)

Last edited by Original Burnedfingers; 2nd January 2012 at 11:34 AM.
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