Images of items I have purchased.

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Feek

Feek

Feek

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Tealc said:
I like the way they've packaged the 4 transistors together on the oscillator to keep them at the same temp.
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Two of them are BS170s as heaters, one is a temperature sensor and the last one is an oscillator transistor. It's a basic Colpitts oscillator.

Tealc said:
What do you need one of those for? Something to do with radio perhaps?

What sort of accuracy does it have? Can't be that good using all through hole components.
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Yup, it's the heart of a very low powered transmitter used for running very low power tests, typically less than 200mW output. I have it transmitting WSPR and QRSS, the latter of which is very slow Morse code with the dots being six seconds in length. The slow speed and tiny bandwidth (4Hz) makes it very easy to receive when the signal is barely above the noise level.

Regarding accuracy. Well, it's GPS calibrated so it's incredibly accurate and being an oven, it's very stable. Once it reaches the operating temperature which seems to take around ten minutes, it's spot on frequency and with a drift of less than 0.02Hz in the last 24 hours, it's very good.
 

Chris [BEANS]

Chris [BEANS]

Chris [BEANS]

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Feek said:
Two of them are BS170s as heaters, one is a temperature sensor and the last one is an oscillator transistor. It's a basic Colpitts oscillator.


Yup, it's the heart of a very low powered transmitter used for running very low power tests, typically less than 200mW output. I have it transmitting WSPR and QRSS, the latter of which is very slow Morse code with the dots being six seconds in length. The slow speed and tiny bandwidth (4Hz) makes it very easy to receive when the signal is barely above the noise level.

Regarding accuracy. Well, it's GPS calibrated so it's incredibly accurate and being an oven, it's very stable. Once it reaches the operating temperature which seems to take around ten minutes, it's spot on frequency and with a drift of less than 0.02Hz in the last 24 hours, it's very good.
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Genuine question.... What??

I genuinely don't understand?! An 'oven', that you can use for transmitting very slow Morse code?!

Am I completely misunderstanding? Why would you wan't to send very slow Morse code?! What's that got to do with an oven???

Is it for any actual practical purpose, or is it strictly a hobby type thing because you like knobbing about with electronics?

Edit: Googled 'Colepitts oscillator'. I'm none the wiser.

2nd Edit: I've googled uses. Don't bother trying to explain:-

Some Website said:
Applications of Colpitts Oscillator

It is used for generation of sinusoidal output signals with very high frequencies.
The Colpitts oscillator using SAW device can be used as the different type of sensors such as temperature sensor. As the device used in this circuit is highly sensitive to perturbations, it senses directly from its surface.
It is frequently used for the applications in which very wide range of frequencies are involved.
Used for applications in which undamped and continuous oscillations are desired for functioning.
This oscillator is preferred in situations where it is intended to withstand high and low temperatures frequently.
The combination of this oscillator with some devices (instead of tank circuit) can be used to achieve great temperature stability and high frequency.
It is used for the development of mobile and radio communications.
It has many applications used for the commercial purposes.
Hence, this article discusses in brief about the Colpitts oscillator, theory, working and applications of Colpitts oscillator along with its tank circuit are used in free electronic project kits. For more information regarding the Colpitts oscillator, please post your queries by commenting below.
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I still don't get it. I'll move on with my life.
 
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