ΜBITX
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Revision as of 00:20, 13 August 2018 by Firespeaker (talk | contribs)
Notes on µBITX assembly and use.
Assembly
Parts that took some time to decide on approach to:
- Case: used a cookie tin as a case.
- Mic assembly: TODO
Still planned:
- check power output on various bands
- get on the air!
Antenna setup
Inverted V dipole made with Amateur Radio Supplies 20m dipole antenna wire (two 18' strands, trimmed, wrapped around insulators, strung up in attic) and 450Ω window line.
- Originally was sent two 16ft strands, which is really too short. Customer service was great and sent me the 18ft strands and a prepaid return envelope for the 16ft strands.
QRPGuys Multi Z Tuner
QRPGuys 12W dummy load
- Items from QRPGuys took about 2 weeks from date of order to arrive.
Mods
Applied during assembly:
- Added a fuse before diode (succeeded, afaict)
Attempted after tested working:
- Mitigating heat on LM7805:
- Added a small 5V switching power supply before LM7805 (failed; created too much noise)
- Relocation of LM7805 to case (succeeded, but got leads switched the first time and smoked the nano)
- Dim LCD (failed—no effect)
Plan to attempt at some point:
- TX LED
- SWR meter
- Red-on-black display (for night-time operation)
- Foot-pedal controlled TX
- Some sort of audio pre-processing?
- Leveling out power?
- Fix filters??
- Use CEC firmware