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0.1 uf electrolytic and 0.1 pf capacitors

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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.?

I mean pushed into sockets and not soldered.
 
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.
 
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
 

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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.
 
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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.:)
 
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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.
 
If you are saying each parallel conductor on bread-board is 2 - 25p, imagine the capacitance on strip-board!!

I think the layout shown on strip-board in the photo is an absolute farce.
Apart from the fact that the Q of the tank circuit is poor, the layout is so open that the circuit will be very susceptible to handling. You cannot design a 100MHz circuit like that. The 1n across the oscillator rails is insufficient and the air trimmers should trim 22p caps.
 
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.
 
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But don't forget, the only strips that matter on bread-board are those connected to the tank circuit and if the adjoining strips are not used, the problem does not exist.
Don't get me wrong, I would not use bread-board for 100MHz circuits, expecially those that employ Tank Circuits as the Q of the tank section is very important and you cannot expect to get anything out of a circuit that is poorly designed. That's why I brought it to attention. But you can't say that bread-board has a lot of stray capacitance. But it certainly has a lot of unwanted impedance - especially around the tank section, where unwanted (or stray) impedance can be so high that the circuit fails to oscillate completely, or fails when you bring a hand near the oscillator.
 
Colin, I'm not sure why you're having trouble understanding this, the capacitance is there no matter if the row is used or not.

The capacitance decreases with each neighboring row that is vacant because they're in series, but it's still there. Any circuit over 10-20mhz or so if moved to a project board would have to be retuned. I have heard of many people setting up oscillators on a breadboard that they get to work just like they wanted to and when they move them to point to point or strip board and they don't work anymore because they fail to acount for it.

Anyone that has used a microcontroller or cmos logic gates and left lines floating knows this because the capacitance is high enough that any nearby floating gates will follow the nearest signal line they can find like a sick little puppy.

Inductance is an issue as well though I've never seen any static numbers for what kind of inductances there actually are.

Basically anything over 10mhz you want to work reliably in a real circuit should probably be wire wrapped or point to point soldered, unless you're fine with it working only on the breadboard.
 
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You could chop off the regulator and the additional RF power stage, but it wouldn't be as stable (frequency drift) and wouldn't have the same range (Output power):
 

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I have sold over 100,000 kits and the audio is so good that you cannot tell if someone is talking in the next room or the sound is coming from an FM radio.
No.
Your FM transmitters do not have pre-emphasis (treble frequencies boost) like FM radio stations use. So your FM transmitters will sound muffled on an ordinary FM radio because all FM radios have de-emphasis (treble frequencies cut) and therefore your transmitters will sound bad with no treble frequencies like an AM radio or like a stereo with its treble tone control turned all the way down.

My FM transmitter sounds perfect because it has pre-emphasis.
 
I have already suggested visiting my site and building one of the following FM Bugs:

See Wasp or Voyager on <snip> website for a much-better design

<mod edit: self promotion deleted. If you have content to share, please post directly to ETO. Do not link to your own personal website>
 
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Your FM transmitters do not have pre-emphasis (treble frequencies boost) like FM radio stations use. So your FM transmitters will sound muffled on an ordinary FM radio because all FM radios have de-emphasis (treble frequencies cut) and therefore your transmitters will sound bad with no treble frequencies like an AM radio or like a stereo with its treble tone control turned all the way down.

You have absolutley no idea what you are talking about.
An FM station through one of my bugs sounds exactly like the radio station coming from the radio.
I will be putting your circuit on my website under "Spot The Mistake" as it is one one of the worst layouts I have seen in my life for a 100MHz design.
I will be showing readers "what not to do."
I remember the day "strip-board " came in and only an idiot woud use it.
It doesn't look professional and I would certainly not show anyone I had used it - or recommend its use.
 
Post audio received on your respective devices record them in .wav format with NO alterations of any kind. A modern pop radio station will generally do. A good 30 seconds worth of audio, and since I don't know jack about FM radio design I'll judge the relative quality of the rendered audio. By ear and with through spectrum analysis. And Colin if you look at audioguru's board and think that's "not professional" Then you've got a serious problem! Would you care to post some live photo's of the last few boards you personally made so we know what a real professional is capable of?
 
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Colin, my apologizes. I wasn't commenting about any portion of FM transmitter design. I simply want you to use a common FM receiver to record the audio from your transmitter. Post those .wav clips and I'll judge them, both with my own ear and from a spectrum analyzer, and post my results. For best results you should feed your FM transmitter with hi-fi audio, or better yet, white noise.
 
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