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Re: What are you going to build in 2004?

2004-01-01 by charlesosthelder

Wow!  There's a question!  

I've just finished a dual tube VCA/waveshaper (modified CGS starved-
plate design)and I'm still trying to design the perfect random CV 
generator.  The first design is fun but I want to limit the upper-
frequency end.  The next design will start today with two XR2206 
function generators.  This IC has FM and AM inputs and two 
simultaneous  outputs.  Simplify, simplify...

I promised a friend that I would rebuild his Fender Twin Reverb.  
It's been a while since I've worked on a 100 watter.  Finding 500 
volt caps is a pain, but everything else is readily available.  The 
worst part will be testing the beast.  Big amps are like grenades - 
just because they're loud doesn't mean you want to hear it!  This 
past November I built my own 1 watt tube amp, and my 100 watt 
Marshall Super Lead has been detuned to 15 watts (still too loud!)for 
recording.

There's a simple condenser mic design in this month's QST (amateur 
radio magazine)that looks like fun.  It'll require designing a new 
amplifier for a balance output.  Really, check this out!

Ken Stone told me that he'd never tried a starved-plate version of 
the sheet beam modulator tube waveshaper.  To me, that was kinda like 
throwing down the guantlet!  The 6JH8 is ordered...

There's so much to be done with VC precision rectification.  Makes me 
double my coffee order just thinking about it.  Anyone else?

Let's see...I've got an old Langevin passive EQ (this is truly a work 
of art!) and a pile (really-ask my wife!)of mic and line preamps from 
WISN in Milwaukee that'll make a great mic/line preamp/mixer.  I've 
been cleaning and recapping those for a bit.  There's two Heathkit 
tube preamps that need refurbishing.  I've got five of these little 
mic/phono preamps that GE made in the '50's when magnetic phono 
cartridges became popular.  Two LC phono EQ's-one Pickering and one 
Astatic, both NOS in the boxes from the '40's-early'50's- that should 
have a home just because they're cool.

MOTM brothers and sisters, it is not my intent to try to out-do 
others on this list.  Given the likes of JH, Paul, Old Crow, and MANY 
others, my list surely pales in comparision to what they've planned!  
I want to make it clear that my work is available for others to 
scrutinize, rehash, copy, or just futz with.  Experimentation is 
GREAT and it should be SHARED FREELY so the most popular designs 
evolve into useful devices for many.  Hopefully, this entry will spur 
even one person into playing with a breadboard and a pile of parts.

Also, do not hesitate to ASK FOR PARTS, HELP, IDEAS, or just 
encouragement.  As we all witnessed, the knowledge base of this group 
is enormous.  If something isn't clear to me (e.g.-my little power 
supply snafu), I'll ask this list rather than waste time looking in 
the wrong directions.  

Now let's get crackin'!

Chub

ps- really, ask for parts.  You should see this mess.

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