cathode follower with gain

trancy · 3rd March 2004, 09:34 AM

can someone show me, how to build mu CF with ECC88, power supply +/- 50 V or 100V, with gain 3, input res on my amp is 4,7Kohm (3,5V ,700uA)...

thanks

fscarpa58 · 3rd March 2004, 10:18 AM

Hi trancy

A CF alone has no gain ( gain <1).
It has to be preceded (or followed) by a gain stage.

Federico

trancy · 3rd March 2004, 10:26 AM

Quote:

Originally posted by fscarpa58
Hi trancy

A CF alone has no gain ( gain <1).
It has to be preceded (or followed) by a gain stage.

Federico

yeah ....like that...

I was trying to make a schematic in micro-cap, but probably Im too stupid.....

fscarpa58 · 3rd March 2004, 10:33 AM

Hi trancy

Last year I was in Bled for my white week holidays
Beautiful place.

I'll send you a pic for a 6dj8 common cathode
followed by a CF.
But since a gain of 3 is very low I have to
attenuate the input or the output.

Federico

Sch3mat1c · 4th March 2004, 02:41 AM

A mu stage has a CCS-loaded triode (although it should work with pentodes just as well) with CF output. Think about it!

Tim

JojoD818 · 4th March 2004, 03:36 AM

Trancy,

Attached is a cathode follower followed by a common cathode stage. I was told that tubes such as 6DJ8, 6922, ECC88, 6N1P can be used for such a configuration.

Federico,

Would it be possible for you to provide values for the resistors using 6N1P and ECC88 tubes? I have a couple of 6N1P sitting here waiting to be used.

Thanks!

JojoD

trancy · 4th March 2004, 06:37 AM

Quote:

Originally posted by fscarpa58
Hi trancy

Last year I was in Bled for my white week holidays
Beautiful place.

I'll send you a pic for a 6dj8 common cathode
followed by a CF.
But since a gain of 3 is very low I have to
attenuate the input or the output.

Federico

wau...I live near by Bled, next time we should meet...

Iam waiting for your sch. .....thanks a lot...

fscarpa58 · 4th March 2004, 12:53 PM

Hi trancy

Sorry for the delay, but yesterday
I had not success in connecting
to the forum.
here is the pic

ciao

Federico

fscarpa58 · 4th March 2004, 12:59 PM

JojoD

what is the input resistance of the amplifier?
( I am supposing that this is a preamplifer
which will drive an amplifier)

ciao
Federico

trancy · 4th March 2004, 01:36 PM

thanks a lot federico, I will report how it works soon...I hope without smoking signals....

3rd March 2004, 09:34 AM	#1
trancy diyAudio Member Join Date: Feb 2004 Location: Slovenia	cathode follower with gain can someone show me, how to build mu CF with ECC88, power supply +/- 50 V or 100V, with gain 3, input res on my amp is 4,7Kohm (3,5V ,700uA)... thanks __________________ too much is just enough

4th March 2004, 02:41 AM	#5
Sch3mat1c diyAudio Member Join Date: Jan 2003 Location: Milwaukee, WI	A mu stage has a CCS-loaded triode (although it should work with pentodes just as well) with CF output. Think about it! Tim __________________ See my Electronics webpage -- the home of Vacuum Tube Drag Racing. The key to being a successful Audiophile: "I reject your reality and substitute my own!"

4th March 2004, 01:36 PM	#10
trancy diyAudio Member Join Date: Feb 2004 Location: Slovenia	thanks a lot federico, I will report how it works soon...I hope without smoking signals.... __________________ too much is just enough

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Question about direct coupling a anode follower into a cathode follower.	G	Tubes / Valves	45	29th July 2004 07:47 PM
cathode follower	ackcheng	Tubes / Valves	2	6th July 2004 04:12 PM
Cathode Follower? Yay or nay?	SHiFTY	Tubes / Valves	25	16th March 2004 07:38 AM
cathode follower	olvrkrg	Tubes / Valves	3	21st February 2004 10:49 PM

3rd March 2004, 10:18 AM	#2
fscarpa58 diyAudio Member Join Date: Nov 2003 Location: Genova, Italy	Hi trancy A CF alone has no gain ( gain <1). It has to be preceded (or followed) by a gain stage. Federico

3rd March 2004, 10:33 AM	#4
fscarpa58 diyAudio Member Join Date: Nov 2003 Location: Genova, Italy	Hi trancy Last year I was in Bled for my white week holidays Beautiful place. I'll send you a pic for a 6dj8 common cathode followed by a CF. But since a gain of 3 is very low I have to attenuate the input or the output. Federico

4th March 2004, 12:59 PM	#9
fscarpa58 diyAudio Member Join Date: Nov 2003 Location: Genova, Italy	JojoD what is the input resistance of the amplifier? ( I am supposing that this is a preamplifer which will drive an amplifier) ciao Federico

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read