Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: chocopower on January 03, 2012, 11:01:49 am

Title: TVM PK200/J P.A. tube amp.
Post by: chocopower on January 03, 2012, 11:01:49 am

I friend of mine get a TVM PK for 300€.
is like that one:

http://jpegbay.com/gallery/001149343-7.html#7 (http://jpegbay.com/gallery/001149343-7.html#7)

using the pictures i draw preliminar schematic. (sorry for the weird draw).
Is that right or i´m totally out of my mind?

Before the "imput" there are four imput jacks with bass-treble-volumen, where, i suposse, there some kind of solid state devices.

Title: Re: TVM PK200/J P.A. tube amp.
Post by: PRR on January 03, 2012, 06:22:48 pm

> Is that right

That would work.

Title: Re: TVM PK200/J P.A. tube amp.
Post by: chocopower on January 04, 2012, 02:02:52 am

Thanks, PRR.
I never had seen a PI like that. Everyday is a good day to learn something new.

The owner call me tonight and said amp works perfec with a very clean sound. He tryed guitar, bass, organ with succes in every instrument.
Is safe bypass V1 cathode with a cap or is gonna unbalance the signal between the two sides?

Title: Re: TVM PK200/J P.A. tube amp.
Post by: kagliostro on January 04, 2012, 02:32:19 am

The PI is the first tube on the left of your schematic and it looks like an usual LTPI

the second tube looks like an amplifier (gain stage) before of the PA tubes

Kagliostro

Title: Re: TVM PK200/J P.A. tube amp.
Post by: chocopower on January 04, 2012, 02:40:23 am

Silly me..... Now i can see it....