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Re: opinions [message #8784 is a reply to message #8782]

Sun, 30 January 2005 18:24

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

O'Kay so Ra is the plate to plate load impedance?

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ooops.... [message #8785 is a reply to message #8784]

Sun, 30 January 2005 18:40

PakProtector
Messages: 935
Registered: May 2009

Illuminati (2nd Degree)

hey-Hey!!!,
my bad, I forgot to answer the question. I got distracted in my ranting...

Ra is the SE load in the example given. You'd double its value to expand the model to PP.

regards,
Douglas

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Re: ooops.... [message #8786 is a reply to message #8785]

Sun, 30 January 2005 19:05

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

Ranting??? I didn't hear no stinkin' ranting. Was that what that waaas??
Seriously Looking at the post I may have mis-phrased that, please allow this old man to slip up one time.
So that means it is the load impedance reflected to the full primary by the load on the secondary? For PP that is.
BTW your pre-amp sure looks nice. There is a total of 8 tubes? And those three corner screws go into a corner block? Thanks for the hand-holding; figuratively that is.
That Transformer; is that a Heybeour? The OPT on the right, nice and shiny, hope mine looks like that! I like the way those coke-bottle 6L6's look BTW if you are considering the amp circuit.

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Re: ooops.... [message #8787 is a reply to message #8786]

Sun, 30 January 2005 19:16

PakProtector
Messages: 935
Registered: May 2009

Illuminati (2nd Degree)

Hey-hey!!!,
The black TX behind the capacitor( silver cylinder ) is the 8039 Heyboer choke. 30 Hy at adequate DC output and designed for L-C service.

the grey box is a Paeco from a HP timer. It ran about 35 12AU7's with a regualted power supply.

The three holes in the front right are for the volume pot and the two input jacks. I wanted short enough runs to avoid shielding if possible. There are two holes in the back behind the amplifier section for the output jacks.

The PS runs two damper diodes, 6AX4's and the amplifier runs 1 12B4 and two 12BY7's per channel. The 12BY7's form the active load/output bufer like the cascode MOSFET circuit used in Guinevere's plate loads. I hope it works, I haven't tried it yet...
regards,
Douglas

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