CHIRP

Jim Unroe wrote:

Vitor,

CHIRP could easily be updated to allow the keying in the same frequency ranges that you have included in your Baofeng software hack. But just being able to upload a given frequency to the radio and get it to show up on the display does not qualify it as being "unlocked".

Back in April a came across a Russian blog that claimed that their testing had indicated that the VHF band of the radio could be expanded. That expansion could even include the 220 MHz range. So I modified my CHIRP and began testing to validate these claims. My results were this.

130.000-175.000 MHz (expanded range)
220.000-269.000 MHz (added range)
400.000-520.000 MHz (unchanged)

Anything outside of these ranges either did not transmit, did not receive or both. So these are currently the frequency ranges that CHIRP allows you to key in to the spreadsheet memory editor for a Baofeng UV-B5/B6 radio. Before the radio will use these frequencies, the band limits have to be expanded to include these frequencies, so the VHF band limits were also expanded to cover 128-270 MHz.

Since then, I have learned that when transmitting on frequencies in the 220-269 MHz range, the radio puts out more RF on the harmonics than it does on the fundamental frequency. Because of interference that this would cause, I have been considering removing the 220 MHz range support for the UV-B5/B6.

Besides getting these out-of-band frequencies to show on the display, what testing have you done to validate that they all (or any part of them) receive and/or transmit?

does this really work with all baofeng models? Is it possible on BF888s?