[Boatanchors] Johnson Viking II Audio Mod Question

[hammadv at comcast.net]

Used a Viking II for a number of years with the stock audio and a crystal mike and 
got good reports all the time.  Is it possible that component aging has changed 
resistor and cap values enough to cause distortion in the old girls??

Kurt  K9ZWY 
 -------------- Original message ----------------------
From: Garey Barrell <k4oah at mindspring.com>
> Scott -
> 
> That sounds like a poor adaptation of the Valiant preamp.  Take a look 
> at the Valiant schematic.
> 
> The Viking II was always known for it's great audio back in the 50's.  
> The Ranger was also known for outstanding audio.  Now I'm sure that was 
> in part due to the fact that many of us were using cathode or screen 
> modulation, but I really don't understand the need for modifying these 
> modulators.  We really don't need "high-fidelity" broadcast audio for 
> communications!
> 
> My Ranger and my Viking II are stock!
> 
> 73, Garey - K4OAH
> Glen Allen, VA
> 
> Drake 2-B, 4-B & C-Line Service Supplement CDs
> <www.k4oah.com>
> 
> 
> 
> Freeberg, Scott (STP) wrote:
> > I've got a gorgous Viking II with a messed up preamplifer modification.  I've 
> looked in ER and online Viking II audio mods, found several, but not like the 
> one here.  The PO replaced both 6AU6 preamplifiers with 9 pin 12AT7s or 12AX7's.  
> The first 12AT7 provides two stages of amplification while the 2nd tube has both 
> sections tied in parallel for a massive driver transformer drive.  
> >
> > Does that mod sound familar to anyone.  The circuitry for that mod is a mess 
> with shorts, messy connections, burnt wire insulation, wires tacked on, etc..  
> The rest of the Viking II connections are clean, its just a mess in the preamp 
> section.
> >
> > I'm thinking of just removing the mess, putting the 7 pin ceramic sockets back 
> in, and putting back to original.  
> >
> > 73, Scott WA9WFA
> >
> >   
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