It won't work very well on a breadboard if at all. Too much stray capacitance and inductance.

There is no "stray capacitance" on a breadboard.
The fact that there is very little "ground plane" on a bread-board makes the circuit susceptible to "stray capacitance" of your hand when tuning the circuit.


The reason it will not work well on bread-board is due to "impedance" not inductance.
The oscillator section should have a low impedance so the voltage produced by the inductor can be passed to the capacitor. These two components make up a circuit known as a TANK CIRCUIT and they will pass energy back and forth (without the need for any other components) when a voltage is applied. The only problem is: the energy passed back and forth will gradually die away due to losses. This is where the transistor comes in. It constantly “tops up” the energy to them and this is how the circuit oscillates. If you have long tracks between the inductor and capacitor or the tracks are thin, more of the energy will be lost in the “track-work.”
Secondly, you want to have a good ground plane so the circuit can push the signal into and out of the antenna.
The positive rail is the “ground-plane” in this design as the inductor is connected to it. The positive rail is also connected to the negative rail via a 22n and thus both rails act as “ground-planes.”
If you use bread-board, the fine wires under the board have a high impedance and will not provide the “tight circuit” you require.

Two faults in the second circuit have been noticed:
The coil has 10 turns, making the capacitor about 20 - 25p for 90MHz. The ideal Q for this frequency is 5 – 6 turns and 39p.
Secondly, the air trimmer should have a 22p ceramic across it so the trimmer only adjusts a small amount of the capacitance. It makes for a more-stable operation and easier to fine-tune

Originally Posted by Gekko022

I don't see why I would have so many problems when the guy in the book made it on a breadboard and tested it and it worked. Then he made it on PC board and only had to adjust the coil a bit.


Why are you telling me there will be so many problems when he had none.

hi Gekko,
When you say 'breadboard' do you mean a project board where the components are pushed into sockets and not soldered.?

or do you mean stripboard [veroboard] where the components are soldered into copper tracks.?

Originally Posted by Gekko022

I mean pushed into sockets and not soldered.

As in a solderless bread board.

Originally Posted by Gekko022

I mean pushed into sockets and not soldered.

hi,
Look at this:

Limitations
Due to large stray capacitance (from 2-25pF per contact point), high inductance of some connections and a relatively high and not very reproducible contact resistance, solderless breadboards are limited to operate at relatively low frequencies, usually less than 10 MHz, depending on the nature of the circuit. The relative high contact resistance can already be a problem for DC and very low frequency circuits. Solderless breadboards are further limited by their voltage and current ratings.

Originally Posted by ericgibbs

hi,
Look at this:

So should I just go right into it and solder everything together?

And I found why the MIC is not getting power. PIC ATTACHED.

And is there a positive and negative side on a mic? Howw do I tell which is which?

Edit its attached nw

Originally Posted by Gekko022

So should I just go right into it and solder everything together?

And I found why the MIC is not getting power. PIC ATTACHED.

And is there a positive and negative side on a mic? Howw do I tell which is which?

no image attached.???

EDIT:
Looking at the circuits I would build the one posted by 'audioguru' at least you will know when you have built it will work.

Originally Posted by Gekko022

Sorry.. its attached now. So should I go right into soldering it?

My 10 pence worth:
Looking at the circuits I would build the one posted by 'audioguru' at least you will know when you have built it, it will work.

Colin, I think you need to rethink that, the spring strips on a breadboard have a parasitic capacitance with each neighboring row of connections of between 2 and 25pf plus whatever inductance is there.

A cap is easiest to visualize as two flat plates separated by a distance, the closer they are and the more the surface area the higher the capacitance. Breadboards are vertical spring loaded strips very close to each other, ideal capacitors. A strip board the surface area is almost 0 because it's effectively two edges facing to each other not two plates facing each other. Why you think it would be higher is beyond me as it goes against basic capacitor mechanics.