Hey guys. So I have been bored lately and decided that I want to make a new intercom for my car.
I made one a long time ago, and it was using transistors for the preamp on the input stage. After about a year of use, I ended up having to replace the transistors from being peaked out too much.
Here are photos of the old one:
Link to download files for old intercom: https://docs.google.com/open?id=0B1h...FZnLUNnbnY0bGs
So I'm wanting to make a new one and trying to only use integrated circuits that way it will be very robust and wont break down as fast. Also it will have better clairity in the sound.
At this point I am planning the intercom to have:
- Input and output for both driver and co-driver.
- Be compatible with Terratrip mic/headphone.
- Input for a HAM radio, this connection will be isolated with an audio transformer. Gain will be set internally.
- Output for a HAM radio, gain will be set internally.
- Audio Compression with one "knob" for controlling threshold, all other parameters like attack, release, gain and compression ratio will be preset and not adjustable.
- One 5 LED VU meter for volume.
- High quality Mic Preamp
- 1.5W Output Amp for the driver and co-driver channels.
I'm thinking of designing a squelch system into it, and also having volume set by Digital Pots, instead of using manual pots with the knob. The digital pots will have push buttons for volume (like the Peltor) instead of knobs (like the Terratrip).
I'm not planning on selling this, just making a schematic for it and maybe a run of boards so us DIY electronics nerds can have a intercom that we built ourselves.
Is there anything else you guys could think of that you would want in an intercom?