How to increase NE555 output amplitude?

Hi, I have the following circuit:
which is able to generate a nice sawtooth waveform. When I provide 13.12 volt as power supply, the max peak of the sawtooth will be near to 8.7 volt. There is a viable way to increase this value at least to the same value of the power supply (13.12 volt)? And can someone provide me a schematic based on my circuit? I suspect that this would be viable using a transistor or an op amp on the output, am I right? If i had to implement  an op amp, I prefer to use a "single power supply" op amp, and a common IC (eg an LM358?)

Kind regards.

How did you measure the peak of the signal?
If you used a multimeter it will be wrong.
A simple transistor is enough to boost the signla to higher level, but won't be more than the supply voltage.

akopelumenuscu (author)  Downunder35m2 years ago
I simulated the circuit then I measured the peak using a "cheap" oscilloscope made by my soundcard.
How I should connect the transistor? As emitter-follower? I will also need a specific value about the base resistor?

You can use any transistor (NPN) that has the specs for your output.
The 555 output drives the base of the transistor.
There are many schematics for doing it from dirty and cheap to fully professional.
For a good start look at simple, single transistor audio amplifiers.
Then combine it with your circuit by matching the input reistors to the level of the 555.

akopelumenuscu (author)  Downunder35m2 years ago
"There are many schematics"

Sure, i've done some search on Google and I've found a billion of different schematics :-), but each circuit claims to be the best solution (from the simplest to the complex), and unfortunately I don't have the skills to judge which would be the best solution. Here at home i have some 2N2222 NPN transistors, and I aim to increase the peak of the output sawtooth from 8,7 to 13 volt (as the power supply), can you suggest me a simple way to wire the 2N2222 as voltage buffer? That would be very nice. Many thanks.