[Jimmy[_8_]]

This is the circuit diagram of a EF86 preamplifier.

https://imageshack.com/i/mv8j8lg

https://imageshack.com/i/2h7pog

https://imageshack.com/i/1a2xf8g

https://imageshack.com/i/5mdk3ng

Then I found a circuit that is claimed to be the same circuit, but how come 5 tubes (below) vs. 6 tubes (above -- stock / original)?


https://imageshack.com/i/3uzdfg

Are they really the same?

Thank you!

[Jimmy[_8_]]

Sorry something went wrong!

Here are the pictures for the stock one that is 6 tubes (V1 to V6).

https://imageshack.com/i/fkkncrg
https://imageshack.com/i/nm3q84g
https://imageshack.com/i/ne4p1ij

And this is the one claimed the same circuit but with 5 tubes on the signal path.

https://imageshack.com/i/n7n0g9g

Are they really the same?? thx in advance!

[Phil Allison[_3_]]

"Jimmy"
Sorry something went wrong!

Here are the pictures for the stock one that is 6 tubes (V1 to V6).

https://imageshack.com/i/fkkncrg
https://imageshack.com/i/nm3q84g
https://imageshack.com/i/ne4p1ij


** The links are still all dead.

Imageshack seems to be down at the moment.


..... Phil

[Jimmy[_8_]]

I try again, no problem.

On Sunday, January 26, 2014 10:31:45 AM UTC+8, Phil Allison wrote:
"Jimmy"

Sorry something went wrong!



Here are the pictures for the stock one that is 6 tubes (V1 to V6).



https://imageshack.com/i/fkkncrg

https://imageshack.com/i/nm3q84g

https://imageshack.com/i/ne4p1ij





** The links are still all dead.



Imageshack seems to be down at the moment.





.... Phil

[hugeshows]

Hi Jimmy,

I'm not familiar with that model, but those two schematics have a lot of differences. Apart from the fact that there's one less pentode in the second version, there's also two inputs for phono and line, two potentiometers (one at each input, and a diagram of the power supply. I'm sure there are more, but I am not really studying the circuit all that closely.

Perhaps there is more than one version of this preamp? The first set of schematics also has a complete section for tape outs and stuff not present in the second. So there are a lot more differences than just the missing EF86.

Somebody more familiar with that amp might be able to tell you what's going on... But at first glance, there are an awful lot of differences there. Anyone here ever seen one of these beasts before?


Cheers,

-forkinthesocket

[Patrick Turner]

On Sunday, 26 January 2014 13:02:30 UTC+11, Jimmy wrote:
This is the circuit diagram of a EF86 preamplifier.

https://imageshack.com/i/mv8j8lg
https://imageshack.com/i/2h7pog
https://imageshack.com/i/1a2xf8g

https://imageshack.com/i/5mdk3ng

Then I found a circuit that is claimed to be the same circuit, but how come 5 tubes (below) vs. 6 tubes (above -- stock / original)?

https://imageshack.com/i/3uzdfg

Are they really the same?
Thank you!

I can't see any thing at any links. Please be so kind to make sure they are http, and not https, and that images are .gif, .jpg, .pdf or some old fashioned easy to read stuff that us old buggers with old PCs can handle without PC trouble.

Patrick Turner.