Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on December 13, 2019, 03:43:32 pm

Title: Revising old AA764 project (6SL7 - 6SJ7 & 1625 Tubes) using a Tremo Nator ?
Post by: kagliostro on December 13, 2019, 03:43:32 pm

I was working to this project a long time ago, then my father (class 1924 and still here with us in a good shape for his age) had a brain stroke and I stopped, since there I did a lot of other things but nothing about this project (my latest work is a dryer for photographic films and modifies to a professional Flash Unit connectors)

At that time, as I want to use octal tube instead of novals, the oscillator was redraw using as base some plans from Steve

Our friend Steve this year developed the interesting Tremo Nator circuit

Here is my modified AA764 schematic

(https://i.imgur.com/BwGyOMy.jpg)

this is the Tremor Lator

(I don't know if it corresponds to the actual Tremo Nator, Steve have you a revised version ?)

(https://i.imgur.com/BoaYOUI.png)

I would be interested to know if I can (and how) adapt the Tremo Nator to my 1625 SE amp

Thanks

Franco

Title: Re: Revising Tremolo on old AA764 project (6SL7 - 6SJ7 & 1625 Tubes) a Tremo Nator ?
Post by: sluckey on December 13, 2019, 03:57:28 pm

Look in Hoffman's schematic library and open the Sluckey link. Download my Bandmaster file. It contains the finalized version of the Trem-O-Nator.

I would try connecting the INT pot directly to pin 4 of V1B. This will put tremolo on both channels.

Title: Re: Revising old AA764 project (6SL7 - 6SJ7 & 1625 Tubes) using a Tremo Nator ?
Post by: kagliostro on December 13, 2019, 04:39:23 pm

Ciao Steve

MANY THANKS

I downloaded the file


(https://i.imgur.com/rJsXILR.png)

As I would like to use a 6SL7, what about the arrangement of the circuit, I copy the Bandmaster oscillator components and use a 6SL7or I can adapt the Vactrol to my old 6SL7 oscillator version ?


(that is a special version you hepled me to plan)


(https://i.imgur.com/OAweC0y.png)

Any idea about ?

Thanks

Franco

Title: Re: Revising old AA764 project (6SL7 - 6SJ7 & 1625 Tubes) using a Tremo Nator ?
Post by: sluckey on December 13, 2019, 04:58:07 pm

I think you can just adapt my circuit to yours very easily. Try this as a test first. Temporarily replace the cathode resistor/cap in your circuit with a red LED. If your circuit still works and the LED blinks, then you are good to go.

Remove the temporary red LED and install a 10K 1/2W resistor, the VTL5C1, footswitch jack, and INT pot as shown in my schematic. You can remove the components and wiring for your V3B as it's no longer needed.

Let us know how it goes. BTW, why are you doing this mod? Is your current trem circuit not satisfactory?

Title: Re: Revising old AA764 project (6SL7 - 6SJ7 & 1625 Tubes) using a Tremo Nator ?
Post by: kagliostro on December 13, 2019, 05:35:05 pm

At the time I was planning this thing I opened a thread about Tremolo on SE amp as research of the "better" way to do it

as all is still only a project and you invented this new circuitry with optimal performances, I'm simply thinking about to use it as to have the best

Thanks Again

Franco