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What is the nature of Baofeng radios' poor receiver performance?

This brand of handhelds has somewhat notoriously poor receivers. I hadn't noticed this much when using them for short distance simplex work on hikes and whatnot, but during recent foxhunts and even with a local repeater this has become apparent. It's especially pronounced compared to a higher end Yaesu HT as well as a Uniden scanner — the Baofeng handhelds we have are incredibly deaf to signals the other receivers can pull in quite clearly in the same location.

What I've noticed is that:

  • holding the monitor button doesn't help — where I would expect to hear at least a faint scratchy signal below squelch, there is just total noise without a trace of the expected signal
  • sometimes the effect is temporary, e.g. on the local repeater it might miss the first five or ten seconds of a known transmission until finally the squelch opens up and the signal then comes in loud and clear! (The timing is unrelated to antenna position and again — total static when/if I hold down MONI during the missed parts until it randomly/suddenly "locks on".)
  • a better antenna doesn't help — we've tried everything from an up-high discone, longer dual/tri-band whips, a roll up dual band "Slim Jim", a monoband (tape measure) Yagi and still just total static where there should be a clean signal. In fact, the stock rubber duck seems the best of the lot as far as slightly more reliable reception goes.

None of these clues quite add up for me. For instance, if the problem were one of sheer overload due to strong FM broadcast on the discone, I would expect the 2m Yagi would help. But the problem can be just about as bad with both. If the problem were just signal/noise ratio I would expect both the up-high discone or the pointed-towards-repeater Yagi to help, but the rubber duck somehow beats them both?!

I've read some blaming of this on "direct conversion receiver" rather than I guess a [multi-stage??] "superheterodyne" architecture. But again this doesn't explain why the signal seems to be either all the way there (opening squelch automatically) or completely absent (not a trace heard when squelch manually opened).

One thing I haven't tried is a bandpass filter to see what difference that makes. But before I would invest in one of those (so far the only off-the-shelf ones I've found cost more than the transceivers themselves) I'd like a better technical understanding of what's making the receive ability of these radios be so inferior. Has anyone come to any real conclusions whether these radios have a specific problem of e.g. "sensitivity" or "selectivity" or "intermodulation" or even just "poorly-tuned AGC" or "bad DSP implementation"? What further experiments should I try?

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  • $\begingroup$ Not sure if I'm allowed to comment here...I wanted to ask a question. I have just come to notice this same exact issue. Local repeaters I'm hearing with a uniden scanner I cannot hear with the baofeng even with my h better antenna. Is the fix just to buy a better HT ? I'm not familiar with FM trap inline, whatever that is. $\endgroup$
    – JimboC
    Nov 10 at 18:40
  • $\begingroup$ What I mean by an inline trap (in my comment on hotpaw2's answer) is that I purchased a "broadcast FM bandstop filter" sometimes called an "FM notch" or other names but sold to a North American market it'd be a filter designed to attenuate signals in the 88–108MHz range specifically. I installed that in between my radio and the antenna, and it did help. I opened mine up and installed a heat sink, but still try not to transmit through it for too long in case it might try unsolder itself — most of the affordable ones are really only designed for receiving and not transmit power levels :-) $\endgroup$
    – natevw - AF7TB
    Nov 10 at 23:24

2 Answers 2

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You get what you pay for. The Baofeng radios take a number of shortcuts in their design to make them cheaper, including leaving out front end filters. The result is that the radio is marginal on suppressing spurious emissions on transmit and has poor sensitivity on receive.

Basically, because of the poor filtering, strong adjacent signals will cause the AGC to turn down the gain making the radio insensitive to the signal you are trying to get.

Ironically, a better antenna makes this problem worse, as it will bring in more noise. A worse or more narrow band antenna may actually help.

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    $\begingroup$ Thanks, though I'm curious specifically what sort of front end filters they should have included? While not allowed to be used as such under the USA's radio regulations, the Baofengs are fairly wideband VHF/UHF transceivers used in a variety of contexts around the world. But then, the better Yaesu or Uniden I've been able to compare them to also have wideband receivers. But you're saying it's [a bank of selectable??] frontend filtering, rather than say an IF filter, that the good receivers include? $\endgroup$
    – natevw - AF7TB
    Apr 27, 2022 at 17:16
  • $\begingroup$ Also what is considered an "adjacent signal"? Anecdotally I tested reception on a Baofeng after adding a 88–108 MHz bandstop ("FM trap") filter and it did receive 2m signals much better! I had been imagining adjacent signals meaning like nearby channels within the same allocation. Or would stations within the FM broadcast allocation centered around 98 MHz also be considered an adjacent signal versus reception at 146 MHz? $\endgroup$
    – natevw - AF7TB
    Apr 27, 2022 at 17:23
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    $\begingroup$ It should have filters good enough to limit it to the band it is suppose to be transmitting on. What is "adjacent signal"? Obviously, it depends on how good your filters are. :) Seriously, though, a good radio is rated on adjacent signal sensitivity, and expressed in decibels difference at one or more specific frequency spacings. $\endgroup$
    – user10489
    Apr 28, 2022 at 1:53
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    $\begingroup$ Any recommendations on a Yaesu upgrade from a baofeng which is CHIRP-programmable??? $\endgroup$
    – niels nielsen
    Apr 30, 2022 at 2:05
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    $\begingroup$ Nearly all radios are CHIRP programmable now. Pick a radio for what functions you want it to do, not for how it is programmed. Or find the list of radios that CHIRP supports (probably all of them) and then compare functions. $\endgroup$
    – user10489
    Apr 30, 2022 at 5:03
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A big clue is that the short ducky antenna seems to allow better reception than the higher gain Yagi. So it could be that the receiver input is overloaded, possibly by signals outside the band of interest.

For a cheap experiment, try using the Yagi, not only aimed away from possibly interfering broadcast stations, but with a high value attenuator in series.

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    $\begingroup$ Thanks, as I mentioned over in ham.stackexchange.com/questions/20840/… there was a drastic improvement in reception when testing with an FM trap inline. (In fact after putting on the filter I actually started receiving a not-incredibly-close repeater just on a coax jumper before I even attached the antenna to it!!) So that might be the/a solution, but it's an inconvenient accessory though. Especially since the filter is likely designed only for RX power levels…. $\endgroup$
    – natevw - AF7TB
    Apr 28, 2022 at 18:32

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