Viking II Interstage Audio/Mod

[N1OHN]

Hello all

What transformer are we using in the 12ax7/6c4 Johnson Viking I and II audio mod?

http://www.amwindow.org/tech/htm/viking2.htm

Thanks!!
Dave

[WBear2GCR]

I seem to recall that people were using a Hammond transformer for most of the rigs that use this sort of circuit.

It's not hyper critical as long as you end up with the requisite swing into the next stage.

                              _-_-

[N8ETQ]

   Hey Dave,


        You may want to consider a Phase Inverter.
Ream out that 7 pin hole for the 6C4 a bit to fit
a 9 pin socket, shove a 12AT7 in it and lash him
up like this.  I'm using one in a ranger to drive
EL34's per the WA3DSP Mods. Very Nice.



   Here is a link to the full article with
links to the schematics. This is for a Ranger
but the phase inverter will work FB on your
V2.


http://www.crompton.com/hamradio/JohnsonRanger/RangerRestoration.html



GL, I have a V2 as well that works but I'm waiting to
get a few other things out of the way before going
over it..

73

/Dan

[N1OHN]

Yeah however I don't know what Hammond works with this mod so I was hoping someone who had completed this mod nows

Thanks! !!!
Dave

[N1OHN]

thanks John... you used it in that mod ?

[W3GMS]

Hello all

What transformer are we using in the 12ax7/6c4 Johnson Viking I and II audio mod?

http://www.amwindow.org/tech/htm/viking2.htm

Thanks!!
Dave

Dave,

The transformer you want is the Hammond 124D.  Use the primary as the secondary and the secondary as the primary. That will give you the right step down ratio.  If the tubes ever draw any grid current it will be up to the task.  I have done several transmitter mods with this transformer and it works out very well.  I do use the hot cathode phase inverter scheme at times when the  modulators are in AB-1.

73,
Joe-W3GMS
B   

[DMOD]

Hello all

What transformer are we using in the 12ax7/6c4 Johnson Viking I and II audio mod?

http://www.amwindow.org/tech/htm/viking2.htm

Thanks!!
Dave

I use the 124B transformer on all of my driver transformer mods but the 124D works as well.

http://www.hammondmfg.com/124.htm

Phil - AC0OB

[N1OHN]

Thanks for your help all!!!!!!!!!!

Dave