cathode follower with gain

trancy · 3rd March 2004, 08:34 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, 09:18 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, 09:26 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, 09:33 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, 01:41 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, 02:36 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, 05:37 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, 11:53 AM

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, 11:59 AM

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, 12:36 PM

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

3rd March 2004, 08:34 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, 01:41 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 __________________ Seven Transistor Labs Projects and Resources

4th March 2004, 12:36 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 06:47 PM
cathode follower	ackcheng	Tubes / Valves	2	6th July 2004 03:12 PM
Cathode Follower? Yay or nay?	SHiFTY	Tubes / Valves	25	16th March 2004 06:38 AM
cathode follower	olvrkrg	Tubes / Valves	3	21st February 2004 09:49 PM


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

3rd March 2004, 09:18 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, 09:33 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, 11:59 AM	#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

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