[chirp_devel] Baofeng UV-3R

[Dan Smith]

> I haven't looked yet to see if the Puxing, TYT, etc. are
> using the same chip or same manufacturer.  Though I suppose
> some of them could be using clones of this chip or that chip
> is a clone of ...  (loop detected).

Yeah, I haven't looked closely. There are several tear down reports of 
the UV-3R out there with everything documented pretty well. The core of 
the device is a single-chip FM transceiver DSP that was built for 
HT-like devices. I imagine that it is plenty good, but requires adequate 
supporting infrastructure to make a useful entire package. It's very 
sensitive, almost to the limit of my (old) service monitor, but I 
imagine that's partly do to the (gross) lack of frontend filtering.

> If you are willing to take the time to type it, I'd love to read it.

There's more information available on the nearly 1000-member yahoo 
group. But:

The microcontroller running the interface is either overtaxed, slow, or 
poorly programmed. Each button requires a significant press to get it to 
register. Long-press secondary functions take way too long. The 
interaction and menu layout, however, is very usable and better than any 
of the other chinese knock-offs that I've seen thus far.

It clearly has some shielding and filtering issues. With the programming 
cable connected, I can transmit on VHF and it will stay keyed (due to 
RFI in the cable) until I unplug something.

The widely-reported second harmonic on VHF is only 6dB down on most 
radios, which is about 54dB below the legal limit. Some people have had 
success adding a filter capacitor to drop it down a bit, while other 
people report it makes it worse.

The VHF image (at about 73MHz) is only attenuated like 20dB. There is a 
bunch of junk coming right out the antenna jack at various parts of the 
band.

The "drop in charger" is nothing of the sort. It's a vertical stand for 
the radio, with a separate bay to charge the battery. The battery is a 
LiOn unit, but there are no charging smarts in the base, just a 5V 
supply directly into the battery. That's, like, not cool. I hope they do 
something smarter if charging it within the handheld, but I think I'd 
check on that before I held it to my face while charging.

The unit itself only takes 5v (not 12 or 13.8) in the side jack, which 
is pretty annoying.

I has the obligatory (apparently China is very dark) "flashlight" on the 
top.

If not for the illegal RF emissions and the dangerous battery situation, 
it might be a worthy "throwaway" radio at less than $50.

-- 
Dan Smith
www.danplanet.com
KK7DS