Baofeng BF-888 frequency adjustment

If you own a Baofeng BF-888 and it just doesn't sound right when transmitting or receiving and you've had it for a number of years, chances are the frequency has dropped significantly, this can be especially a concern if you use these radios on PMR446  in European countries or FRS in the USA (they'll program to both radio services with ease using the CHIRP software which I will cover another time), it can also be an issue on business band, but either way a radio that has drifted way off frequency is always bad.

What causes this is often the age of the crystal used as reference, on my circa-2016 radio, which had done exactly this it is a surface mount device but the board had provision for a through hole device, later devices the crystal is clearly elsewhere but the frequency is still adjustable however the two newer radios I had were not in need of any adjustment).

I spotted the frequency drop by monitoring the radio on an SDR that was stable, to pull it up is a fiddly business, the trimmer (R19 on the board of my circa-2016 one) is very near the crystal, and from pictures of the underside of the board that I have seen this adjustment is the only one in the radio, the trimmer is present on the same side of the board in the newer circa-2024 devices I own, the BF-888 has evolved a lot over the years it has to be said.


The inside of the circa-2016 BF-888

The trimmer to adjust and the crystal next to it

The inside of a later circa-2024 radio, note that the circuit board is much smaller


A close up of the trimmer from the 2024 radio, note no obvious reference crystal, this is likely on the other side of the board

Turning the trimmer requires a suitable tool, you can get those from Amazon (here), DO NOT use a screwdriver (but take into account that on Amazon (including the link I have posted) the tools are often and incorrectly sold as screwdrivers), keep a close eye on the frequency either using a frequency counter or a very stable SDR, I used the SDRPlay RSP1B to do this, I had to tune it to PMR446 channel 8 due to some interference present on channel 1 even with the antenna disconnected from the SDR (I tested with other PMR446 radios).

I have written up a disassembly guide as well as releasing a video to the YouTube channel so please do keep a watch out for that, the video will be released early access to all early access member (£2.99 at time of writing).

Baofeng BF-888 radios are dirt cheap, you can buy them in a lot of quantities and you would still have change left over compared to if you bought potentially a single handheld of similar type from a big manufacturer, they're also sold as legal PMR446 radios by Romanian brand PNI, the difference appears to be the antenna, if you buy a stock BF-888, do make sure to get a programming cable and download the CHIRP software, this helps keep you out of trouble as often these radios are programmed with test frequencies that shouldn't be used.

The video I'll be doing will also show how to pull up the frequency as well as how to take the radios apart.



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