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Old 5th September 2012, 07:44 AM   #661
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Default error ixcp10m45s

Hello,
I want to try in the anode CCS of 6n2p. I've tried with a chip IXCP10M45S unsuccessfully. I tested with resistors 100R, 200R, 300R, 400R, 500R, 600R, 800R and 6K.
No matter the resistance put in "K" I always get the same measure volts, no more than 5V. The red probe placed at the p1 and the black probe at ground of the amp.
The outdoor test chip with alligator clips
Deputy placement scheme.
I go by parts:
Are you well connected in the circuit?
Where do I have to put the red and black probe of the tester to measure?.

thanks

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Old 5th September 2012, 08:36 AM   #662
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Ok, got it, sorry for the confusion I caused.

BTW, I have built this one in the schematic.
Jmillerdoc, how about another two pole/3position switch to change the cathode and anode resistors?
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Old 5th September 2012, 05:21 PM   #663
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This is the chip I'm using. It has a trademark on the left leg. According to the datasheet leg is "G"

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Old 5th September 2012, 06:20 PM   #664
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Hey Alberto, have a look at that, it's among other options for my next amplifier.

Push-pull driver board
It uses the same chip for the same purpose. Looks like you are lacking a resistor like R34. These are some examples of using this chip as CCS

Quoting the juicy part for U3:
"Optionally, R33 can be replaced with a constant current source load, composed of U3, R29, and R34. R34 is to help prevent oscillation (a 1k carbon comp is advised), and R29 sets the current."

For U1:
"The wiper of the balance pot is connected to a CCS circuit, comprised of U1, R19, and R17. R19 is a stopper (carbon comp) and R17 sets the current."

For U2:
"In pentode mode, screen voltage is provided by a CCS circuit (U2, R16, and R18) and is regulated by a VR tube VT2. The CCS current (set by R18) is set to around 20mA. Again, R16 is a stopper (carbon comp). "
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Old 6th September 2012, 09:25 AM   #665
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Hi Regi, thanks for your response.
I connected with the 1K resistor in "G" and a variable resistor of 1K in "K" to adjust the tension.
Nothing, the chip does not change the voltage. Always gives a very small voltage 5V 0.7 V-chip depends on that I have installed. I tested 5.

I do not work correctly or are counterfeit copies.
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Old 29th September 2012, 04:49 PM   #666
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Hello

They reached the new high current regulators. These are the top model at 10m45s, hold up to 1000v. They work well. The Chinese were defective.


I tried one and do not know if I have to adjust as the anode consumption, or as the voltage to be applied to 6n2p.

Without the regulator and old 47K resistance measurements are:

- Anodo1. ---- 200V 4.45 mA
- Anodo2. ---- 200V 4.25 mA
Varies very little.

Installing always the same regulator (alternating the position) and adjusting a potentiometer measures are:

-Anodo1. Adjusting to a consumption of 4mA ----- 174v
-Anodo2. Adjusting to a consumption of 4mA ----- 168V

-Anodo1. Adjusting to a voltage of 200V----- 5.2mA
-Anodo2. Adjusting to a voltage of 200V----- 4.9mA

I do not know if I have to adjust to a consumer or a constant voltage, ie leave the two anodes adjusted to 200V, or adjusted to 5mA.

Regards
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Old 23rd October 2012, 09:38 AM   #667
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Hi,

i have almost all parts together for my KT88 SE, looking forward to assemble all parts.

Greetings from germany,
Tobbe
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Old 30th April 2013, 03:46 PM   #668
alecu7 is offline alecu7  Canada
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Hi Tobbe,

Did you assemble the amp yet?
Top plate looks very good.

alecu7

Quote:
Originally Posted by Wachtfels666 View Post
Hi,

i have almost all parts together for my KT88 SE, looking forward to assemble all parts.

Greetings from germany,
Tobbe
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Old 5th June 2013, 02:35 PM   #669
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Hi,

yes you can find it here:
Project | Homebuilt Hi-Fi - A user submitted image showcase of high quality home built hi-fi components.
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Old 7th August 2013, 09:17 PM   #670
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I built one. Changed the preamp valve to a 6DJ8, dropping the cathode resistor to 500R accordingly, and have the cathode resistor for the power tubes switchable between 480R and 560R to bias either 6550s/KT88s or EL34/6CA7/KT77/KT66. It sounds very good with both 6550s and KT88s in both Triode and 40% Ultralinear. Pentode sounds a bit harsh at the same gain level, but much louder

I used an Allied 6K7VG PT, Transcendar 10W 5k:8 OPTs, and a Hammond 193J P/S choke in C-L-C. Might have overbuilt the P/S a little bit.

Pushing it through a pair of scratch-built Cornscalas, c. 100 dB/W, and it's got plenty of volume, even triode-strapped.

Built in three days, including hand drilling/dremeling the chassis. Only four blown fuses and one burn (from a hot tube) as collateral damage.

Does it sound better than my SS "reference" amp (Twisted Pear Sympatico dual-mono setup which, in passing, is fabulous)? Maybe. I'm not doing double-blind testing. I'm sure the THD for the tube amp is higher, but I also know that the majority component of the THD is 2nd harmonic distortion, which my ears actually like in moderate quantities. Do I like the fact that a homebuilt quartet of glowing vacuum tubes are driving my speakers, and might that bias my opinion of their sound? Yes. Am I enjoying listening as much as I enjoyed building? Absolutely.

My initial thought after an hour of listening was "what am I going to do with this Sympatico setup now?"
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