Railfan Technology > Wouxun KG-UV6X Portable radio--making a lemon into lemonade

Long-time readers of my posts will remember that the Wouxun KG-UV6X portable radio has not been on my "recommended" list for railfan radios for years, primarily because of one huge flaw in its design.  Well, I took my 8-year-old KG-UV6X out of the drawer a few weeks ago and mostly fixed that flaw.  More about that in a minute.

Of late, my recommended analog portable radio for railfanning is the Uniden BC-125AT scanner.  It's a very good performer IF one adds a "performance" antenna to it.  I'm currently using the Diamond RH77CA antenna with good results, except that when I'm carrying the radio on my belt, the antenna almost reaches to my shoulder.  That, and that one should avoid charging the rechargeable AA batteries in the radio, as the charging circuit can malfunction and overheat the batteries and potentially destroy the radio.  Mine did, and had it been on the charger another half-hour, the radio would have been ruined.  That means constantly having to remove and replace batteries in the radio--a pain.

Now, about the Wouxun KG-UV6X.  First, for the record, the KG-UV6X is a Part 90 certified commercial dual-band analog 199 channel radio that covers both the VHF voice, and UHF "train telemetry" (EOT, DPU, etc.) channels--the latter being the electronic "blips" that can notify the listener that a train is in the vicinity--that being important as voice communications are used less and less on the VHF channels.  As is common with most of the Chinese-manufactured radios, both commercial and amateur versions of the radios use the same basic radio chassis, with firmware and software dictating whether the radio is an amateur or commercial model.  In the case of the KG-UV6X, the KG-UV6D is the amateur version of the same radio. For railfan monitoring use, either should work and perform similarly.  The good news about the KG-UV6X is that its receiver will outperform the BC-125AT in both sensitivity and selectivity, even when the BC-125AT is equipped with the performance antenna--and the KG-UV6X will achieve that better performance with its stock 4" antenna.  The KG-UV6X radio itself also is about 1" shorter than the BC-125AT making it more compact to carry.  Audio output on the KG-UV6X is equal to or louder than the BC-125AT with equivalent sound quality.

Now, about that "fatal flaw" in the KG-UV6X.  This "fatal flaw" is common in many, if not most, Chinese radios.  I've talked to various vendors and distributors about this--and it has been communicated to Wouxun--but the flaw persists.  It is this:  when the radio is in scan mode, the keyboard and--more importantly--the side buttons (push-to-talk, and auxiliary buttons) can not be locked out.  In the case of the KG-UV6X, there are 3 buttons on the side of the radio--the push-to-talk (PTT) button, a second button that can be programmed for differing functions, and a third button that is not modifiable (a short press turns the mostly useless flashlight on and off, a long press opens the squelch into "monitor" mode).  The result is that even the slightest bump of either of the two bottom buttons will knock the radio out of scan, often with the user unaware that the radio is no longer scanning.  Pressing keyboard keys, rotating the top channel change knob, or the PTT will also knock the radio out of scan, but all of these require some effort, so the risk of an inadvertent scan stop is relatively low.  There is no software or firmware fix currently available to fix this.

So, I decided to (at the risk of ruining the radio)  perform "surgery" on the radio and remove those bottom two side buttons (the microswitches) from the circuit board.  The procedure was relatively simple, though I don't recommend that anyone do it who does not have some electronics modification experience.  The result:  With those two buttons effectively disabled, the radio will now scan with low risk of getting inadvertently getting knocked out of scan.  The radio scans at decent speed, by the way, and has seen no decrease in performance or usability.  The KG-UV6X uses a proprietary battery and a drop-in charger that works well.  The battery on mine, even though 8 years old, has good capacity between charges. With those mods, the KG-UV6X has now supplanted the BC-125AT as my "go-to" analog portable radio for railfanning.  Just how good is the performance compared to the BC-125AT?  Where I live there are NOAA weather broadcasts available on all 7 NOAA frequencies--at distances away from me from 30-90 miles--the NOAA channels are very close to the VHF railroad channels in frequency, so are good check of reception.  With the BC-125AT, I could only reliably receive the closest 4 NOAA towers.  With the KG-UV6X, I could reliably receive all 7 towers.  Checking the UHF train telemetry channels, the BC-125AT could only receive those channels reliably when a train was within 5-7 miles, the KG-UV6X added a good 2 miles to that, and could periodically receive transmissions from up to 12 miles away.  


One final note--as with the BC-125AT, I strongly recommend getting the vinyl carrying case and belt swivel for the KG-UV6X.  This will protect the radio and make inadvertent pressing of keyboard keys even less likely. The clip-on portion of the case that goes on one's belt is kind of cheesy, in my opinion, but, as is the case with the BC-125AT, the case swivel is compatible with Kenwood's very good belt swivel-holder.

 



Edited 1 time(s). Last edit at 08/21/22 10:59 by WW.

That's great WW, thanks for the report.  So to be clear, neither of the "microbuttons" is truly required to perform any radio function (except opening the squelch, and using the flashlight), for either the amateur or commercial version?

DivergingClear Wrote:
-------------------------------------------------------
> That's great WW, thanks for the report.  So to be
> clear, neither of the "microbuttons" is truly
> required to perform any radio function (except
> opening the squelch, and using the flashlight),
> for either the amateur or commercial version?

The bottom microbutton can only operate the flashlight or open the squelch.  The one above it is a "programmable function" button, but, for railfan use, it is not necessary to program a funciton into it (using the programming software) for the radio to function perfectly well.  For some reason, Wouxun did not allow either of those buttons to have a "Null" or "No Function" option that would have effectively disabled them.  A couple of newer Chinese radios (that I have not tested nor do I own) have the ability to program similar buttons to have no function.  One that is set up that way is the TERA TR-590 that is similar to the KG-UV6X.  The 2 programmable side buttons on it can be disabled via the programming software.  I can't recommend that radio because I've never physically seen one, much less evaluated its performance.  It might perform great or it might not . . .



Edited 1 time(s). Last edit at 08/26/22 10:07 by WW.