[sdiy] inversion, CMOS, etc.

[gavin]

OK, here's a sort of "Grab Bag" message, I've had a lot of ideas lately and
no budget so things are sort of floating around in this abstract space...
1.  I need to invert a logic level pulse from positive to negative.  In
other words the way the signal is now is 0V-+5V,  I need it to go from
0V--5V.  Normally in this application I'd use an OpAmp to invert it BUT this
is a very High Frequency application and So far the circuitry is all TTL so
if I can get away with not building an additional bipolar supply to power Op
Amps I'd like to.  In my understanding a CMOS inverter like the 4049 or a
TTL inverter like the 7404 will just put the signal 180 degrees out of
phase.  Or if I need to use an Op Amp has anyone used the 351 for RF type
frequencies that can vouch for its slew rate at high frequencies?

2.  I also need to take a signal oscillating between -5V and +5V and bring
it up to 0V - +5V while keeping the waveform intact.  A comparator powered
between GND and +5V will act like a schmitt trigger and a half have
rectifier will preserve the upper peak but square off the lower.  Will
mixing in a +5V DC signal through an opamp mixer bring the signal up to 0V -
+10V?  Then I can reduce it with resistance to the appropriate amplitude.

3.  Thinking about pattern generation and analog computers has led me to the
idea of building a voltage controlled comparator.  A simple circuit, to be
sure, has anyone seen or implemented something like this?  

Allright that's where things are over here.  Crazy from the heat.  Let me
know if any of this perks some interest!
Thanks Again
Gavin