Double Balanced Mixer


Intro

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mixer
mixer

Where is/was it Used?

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How I Came Across This and why I Built it

Datasheets:
MRF571
SAM-5
MHW592

Design and Construction

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Conclusion

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Crystal Oscillator Can


Intro

These TTL oscillator cans come in a variety of frequencies from about 32kHz up to 100MHz. The can oscillators aren't as accurate as the discrete crystals but are a lot easier to use in a circuit. All the cans need is a 5V supply unlike the crystals which would need to be part of an oscillator. Like most TTL devices, these cans have a fan out of 10 meaning it can feed the inputs of 10 TTL devices.

How I Came Across This and why I Built it

I have many crystal oscillator cans from my electronics surprise boxes. I have duplicate oscillator frequencies so I picked one and decided to cut it open to see what was in it and how it worked. I was expecting to see a piece of quartz and a die but saw this:

inside_oscillator_can

Since the crystal looked similar to the ones in the discrete devices, I figured I could swap them out and see if it would still work.

removed_crystal

I accidently cut the wire that goes to pin 1 with the dremel when trying to remove the 16.3840MHz crystal. I wasn't careful enough and broke off one of the leads to the crystal.

replaced_crystal

Conclusion

Well it works! I guess I could use these to make crystals oscillate if Iím feeling lazy. Sadly, removing the existing crystal is likely to break something since itís so fragile. It may be more work than its worth though.

modded_oscillator

The top trace is a 4.0960MHz unmodified oscillator output and the bottom trace is the output of the modified oscillator (~3.60MHz assuming the referance oscillator is accurate).