VARPA Project

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This repository contains the source code for:

VARPA: A Variable Power Amplifier

An open source, software-configurable VHF RF power amplifier.

Variable RF output power is achieved using two control circuits:

• Drain bias (supply) voltage regulator
• Input drive attenuator

Silicon Lab's Si4468 tranceiver is used to generate the PA input tone.

RF Primer

If you are new to the topic, you can read:
https://journal.lunar.sh/2024/rf-primer.html

License

This code may not be copied, reproduced, or distributed
without prior written permission. 

All rights reserved. Copyright (c) 2025.

Note:
The content in this repository is strictly intended for
educational purposes only.

See LICENSE.txt for more info.

Info

|----- ( File Structure )
|----- /firmware         C firmware source.
|----- /pcb              PCB files for VARPA system modules.
|----- /scripts          Calibration script and TUI application.
|----- /resources        Datasheets and misc resources.
|----- VARPA.pdf         Compiled Latex project report.
|----- LICENSE.txt       VARPA license.

Signature

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| Lunar RF Labs                         |
| Email: root@lunar.sh                  |
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| Research Laboratories                 |
| OpenAlias (BTC, XMR): lunar.sh        |
| Copyright (C) 2022-2024               |
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