Wednesday, September 21, 2016

Antenna Field Regions

I'm not sure I've ever seen it put so well...

The radiation from an antenna transits three regions as shown.

The transitions between these regions are not distinct and changes between them are gradual. The reactive near-field region is the region close to the antenna and up to about 1 wavelength away from any radiating surface. In the reactive region, the energy decays very rapidly with distance.

In the radiating near-field region, the average energy density remains fairly constant at different distances from the antenna, although there are localized energy fluctuations.

The radiating near-field region extends from the reactive region boundary out to a distance defined as, 2D2/l with D being the largest dimension of the antenna aperture, and l being the wavelength.

Beyond this distance is the far-field region where the angular distribution of the energy does not vary with distance, and the power level decays according to the inverse square law with distance.

Thursday, September 1, 2016

Galaxy S7 randomly disconnects from 5 GHz Wi-Fi - a fix?

I have a Samsung Galaxy S7 Edge. My router is an ASUS RT-N66U.
When I connect my S7 Edge to my 2.4 GHz Wi-Fi SSID, it never drops the connection. However, if I connect it to my 5 GHz Wi-Fi SSID, it drops the connection all the time, seemingly randomly.

I tried the suggestions online, like turning off IPv6 in my router (it was never on), turning off bluetooth on the phone, turning off the bluetooth scanning in the location settings, and other stuff.

What actually fixed it for me was changing my router's 5 GHz channel.  My router had auto-selected 5 GHz channel 161. This is quite near the top of the band, so I moved it down to channel 44 and it never dropped the 5 GHz Wi-Fi connection after that.

I hope this helps someone somewhere!

Tuesday, May 19, 2015

Reasons I switched back to iPhone.

Yeah, that old battle...
In mid-2013, after seeing previews of iOS7, I made the decision to try out Android after several generations of iPhone.  Initially I was happy with it. I saw the iPhone and the imminent release of iOS7 as lacklustre, boring, and more of the same... I wanted a change. The HTC One M7 had just been released, so I decided to take the plunge.

At first, Android was a breath of fresh air.  It was different, and I could CHANGE THINGS!

  • Don't like the font?  Change it!
  • Don't like the icons?  Change them!
  • Don't like the colours?  Change them!
  • Don't like the keyboard?  Install a new one!
  • Don't like the home screen, or the launcher?  Change it!
  • Want access to apps that let you do amazing and cool stuff with the user interface?  They're there!
  • Want to root your device and play around on the command line?  No problem! get the idea.  Android is massively customizable, and that was the initial draw.  You weren't locked into accepting anything about the device, it seemed.  You could change almost EVERYTHING.

Changing almost everything sounded like a veritable mine of awesome. I could have my phone the way I wanted it, how I wanted it to look.

Actually, it's a nightmare.

There were SO MANY customization options that I was never happy with it. I was always changing something, tweaking something, trying new fonts, launchers, keyboards, sounds, rooting, un-rooting...

If you're a nerd, this sounds like heaven.

The difference is, I'm a nerd for a living. I mess around with electronics and technology every day. When I come home from work at the end of the day, I don't need another technological distraction.  I don't need another puzzle to solve, or something else to tweak.  I'd like it if my phone would just work, and not lure me into more technical playtime.  The temptation freedom to idly do anything I wanted to my phone and make it look just not quite how I wanted it was too much.  Like I said, I was never happy.
Why didn't I just leave it how it was?  If you're a nerd, you understand.  Given the virtually limitless possibilities to play around with the OS, it's almost impossible not to get drawn in.

Android 5.0 - The nail in the Android coffin, for me.

After HTC One M7, I had an HTC One M8, then another M8, then a Samsung Galaxy S5 (you can read about that technical support nightmare here) and then I switched to Verizon, on an LG G3. Android Kit Kat 4.4.2 was the operating system and it was fine.  Of course, I was still drawn into messing with it all the time, fighting bugs and incompatibilities between launchers and apps mainly.

Funny, but if you want to live on the bleeding edge, be
prepared to pay for it in some non-relaxing way.
The much fanfared and touted Android 5.0 launched. The "material" design was more like an iPhone's GUI and I was eager to see that, since I was obviously already missing my iDevices.
Unfortunately, any design overhaul was massively overshadowed by terrible bugs in Android 5.0.  On my Verizon LG G3, I saw a myriad of issues, such as:

  • Slow battery charging.
  • Fast battery discharging.
  • SD card activity high, using battery and heating up the back of the LG G3.
  • No app notifications when on WiFi, sometimes. Notifications all flood in when WiFi is turned off.
  • No silent mode. Apparently replaced with a "dead" mode, which stops the notification LED, and even silences your alarms in the morning. What use is this?
  • Extremely slow WiFi.

Comments such as "How do I remove this HORRIBLLY ANNOYING lollipop update?" and "how i can back to the previous update plllllllllls !!! I HATE this one" (and WAY worse) are common on Reddit and online support articles.

There is no "legit" way to downgrade to Android 4.4.2 Kit Kat, but I did manage it using the LG Flash Tool. I used 4.4.2 until I switched back to iPhone.

When I switched back to iPhone, the associate in the Verizon store was very candid about Android 5.0's issues. He said that people complaining about, or having trouble with Android 5.0 consititute two thirds of their support issues at the moment. Not good.

The lack of freedom to customize was one major reason why I switched from iOS to Android. I saw this as a downfall in iOS, but in hindsight, that is the very reason why I switched back.

Android's level of customization is proportional to its time-vampire qualities, and Android 5.0's bugs make an otherwise excellent device irritating and borderline useless in some respects.

Switching back to iPhone after two years, several "flagship" devices, and a few iterations of the Android OS was the best decision I've made regarding phones/mobile devices.  There's just something almost intangible about the operation of iOS that Android just doesn't capture.
Aside from that, if you want something that is attractive, clean, sleek, just works when you want it to, and doesn't suck what limited spare time you have out of you - get an iPhone.

Thursday, April 2, 2015

The Wrycast

Our (severe) weather page is called The Wrycast.

You can find it here:

Also, LIKE our Facebook page:

And, follow us on Twitter:

It's been a while since I've posted on here.  I've been busy with life, and with work.
I've also been getting fired up about Storm Season 2015 here in Central Oklahoma.
Hopefully it'll be an active and safe one!
If you're in Central Oklahoma and you like severe weather, or just weather in general, do visit/like/follow us via the links above.


Friday, December 5, 2014

RF Calculator Apps (Android)

Here's a couple of really nice calculator apps for your Android device...

Lighthorse Technologies have their own app:
...they also have a mobile web page also, at

everythingRF also have their own app, and I tend to prefer the layout and user fiendlyness (sic) of this app over the previous one.

If your're security conscious, this app requires no special permissions in your device.

They're all handy, and they all offer something slightly different, or more or less than the other.  It would be nice if they would collaborate and release an app with everything in it.

If you read this, and have a favourite, leave it in the comments!


Wednesday, November 26, 2014


In early October, I started seeing failures in sending SMS (text) messages on my HTC One M8 (Android 4.4.3).
This is a timeline.  Please, enjoy.

  • Send using default text app.  FAILED.
  • Uninstall Textra (3rd party excellent text app).
  • Send using default text app.  SUCCESS.
  • Reinstall Textra.
  • [time, and several messages pass...]
  • Send using Textra FAILED.
  • I notice this only happens AT HOME, and surrounding area.  If I drive up the road, or go anywhere else, it's fine.
  • Uninstall Textra again.
  • Send using default text app.  FAILED.
  • Restore HTC One M8 to factory defaults via bootloader menu.
  • Keep everything as stock, just for test.
  • Send using default text app.  FAILED.
  • Call AT&T support, they have me send a test message to 151, which is their SMS test number.  SUCCESS.
  • [time passes....]
  • Send using default text app.  FAILED.
  • Call AT&T support, they have me send a test message to 151 again, SUCCESS.
  • Read into how AT&T's system works. The carrier backs off to HSDPA (AT&T call it "4G", but it's really just an enhanced 3G) mode for data when on voice calls.
  • Wait until messages fail again, make call to voicemail, send text while listening to voicemail, SUCCESS.
  • Repeat.  Verify.
  • Call AT&T support and state that I intermittently can't send SMS text messages while on LTE, and only at, or around my home location.
  • They look into towers near my home location and tell me two of three towers close to me are "Degraded" and are due for repair by the 27th of October.  The LTE tower I am on is overloaded due to this, and this is why my sending is failing intermittently.
  • 27th of October arrives.  I cycle power on my phone, and try again.  FAILED.
  • Call AT&T support.  They say that it looks like the issue with the towers hasn't been fixed after all, and I should expect a fix on November 7th.
  • November 7th arrives.  FAILED.  I call AT&T support again.  I should point out that I'm dealing with a different person each time I call support, and each time I have to give them the whole story, with every troubleshooting step I've done, and correct my address, which it seems they cannot fix either.
  • This time, support tells me that they need to re-register my SIM card. "Because this ALWAYS fixes this exact problem".  Cynically, I agree to hang up, switch off my phone for 5 minutes, then switch it back on again.
  • Call AT&T support again.  The tower problems haven't been fixed AGAIN, APPARENTLY...  I should expect a resolution by November 14th.  This time, a support person is actually assigned to me, and opens an urgent support case to "make sure this is taken care of".
  • In the meantime it is suggested that I go to the AT&T store to get a replacement SIM card.  I arrive at a busy AT&T store, and since I just want a SIM card, they give me one so I don't have to wait.  I get home and realise they gave me a microSIM card, not a nanoSIM. It is the wrong SIM card.  I visit another AT&T store the next day and have them replace it.
  • Discovered a free app which lets me easily disable LTE.  Now I can send/receive text messages reliably when at, or around my home location.  I recommend this app - it works, and it allows you to select between LTE, WCDMA, CDMA, GSM, EvDo, etc, and seemingly any combination of:
  • Did some testing while out and about in the local area.  LTE performance is blistering. 50Mbps down, around 20Mbps up.  Send a text message?  FAILED.
  • November 14th arrives.  I get a text message to say my case is marked as resolved, and closed.  I call AT&T and they tell me that the towers are fixed, and their "technicians" cannot find any issue with LTE or text messaging in my home area.
  • AT&T decide to open a new, I guess MORE URGENT support case, since the problem is still there.  They don't understand it.  I don't get it either.
  • November 18th, my assigned tech support associate calls me and tells me that despite repeated visits, they cannot find any issues with the towers in my area.  They would like to replace my HTC One M8 under warranty.  I am ready to try anything at this point, so I agree.
  • November 20th.  Replacement HTC One M8 arrives.  I unbox, update OS to 4.4.2 (apparently 4.4.3 was pulled by AT&T due to some customers seeing excessive battery drain) and test text messages. SUCCESS!
  • No, wait.  FAILED again.  "Failed after numerous retries" - the same error I have seen all along.
  • I have intermittent SMS text send failures when on 4G LTE, and only in my home area.
  • Verified that this isn't an issue on 4G non-LTE.
  • No problems seen in any other location when using 4G LTE.
  • It is not AT&T's network/tower at fault.
  • It is not a signal level issue.
  • It is not the SIM card at fault.
  • It is not the device at fault.
  • It is probably not local interference (problem exists in my home and the local vicinity.  Also for a mile or so to the SE/S/SW directions), unless there is something monstrous going on in the area.
  • If I disable 4G LTE, and use 4G HS(D)PA, everything works fine.
What now?
  • November 23rd, I post the following on Twitter: ">6 weeks, MANY support calls, 3 tech cases, new SIM, replaced device, and still no fix for my texting issue in my home area. Come on, @ATT !".  This causes @ATTCares to direct message me on Twitter to find out how they can help.  I give them the whole story.  They look into it.  They discover there is actually TWO cases open.  They close one which still left a tower investigation case open.
  • November 24th, @ATTCares calls me back to verify that their engineering team cannot reproduce the problem that I am seeing.  I enquire about switching to a different device.  They tell me that will be handled by my assigned support associate/warranty dept.
  • My assigned tech support associate calls me back to see if the replacement phone has fixed the problem.  I tell him it hasn't.  We decide to replace the device with a different phone.  He tries to give me a Samsung Galaxy S4 Active.  I tell him I don't have any need for swimming with my phone, and I'd like a Samsung Galaxy S5 to try.  So, he apparently sends me a 16GB Galaxy S5 to replace my 32GB HTC One M8.  I will have to handle this one later.
  • Shipping notification email arrives for the Samsung Galaxy S5.
  • Shipping notification email arrives for the Samsung Galaxy S4 Active.
Really?  Why did they send me two devices?
I'm really glad I saved the microSIM I was given in error, since I bet they warranty dept didn't send one with the replacement Galaxy S5. be continued...

Update 12/4/2014:

Here I am now with a Samsung Galaxy S5.  Is my texting issue fixed?


I can't wait for my assigned technical support dude to call me, so I can let him know.  Nothing has changed.  Not a thing, except that I like the S5 a bit better than the HTC One M8.

Oh, I followed the shipping notifications for the Galaxy S4 Active... it ended up in Memphis.  Was I sent someone elses tracking information?  Did they realise they'd sent me two devices and redirected it home?  Who knows.

Can you believe it....?
This is STILL not finished!

Update (sometime in Jan 2015):

It magically fixed itself.  By magic, of course.  
It's been a long long time - since 2002, AT&T.  It's been an interesting ride, too.  Expensive, and fun.
I'll be leaving you soon.  I mean... you can't even get the right name on the bill!

Monday, September 8, 2014

Baofeng UV-5R modulation fix

Here's a post which was on my previous website, which was popular.  This modification was originally done by Colin G4EML from the UK.

I had seen this method suggested on some discussion boards but it wasn’t backed up by any test data or any real-world results.  Colin’s post was.  I contacted Colin to see if I could put this method up here on this site, and he agreed.  I have not tried this method myself (yet!) but something tells me that it is the final word in fixing this low modulation issue.  Read on!

I decided to have a close look at the low modulation problem on my UV-5R. Checking on a test set and feeding in a tone on the mic input showed that the deviation was set correctly and limited at 5KHz for wide and 2.5KHz for narrow.
However to get the full deviation I had to use a signal level of about 10 times that provided by the internal mic. That just confirms that low mic gain is the problem not the deviation setting.
Looking at the schematic showed that there is already a convenient amplifier in the Vox circuit. As I never use Vox I decided to mod the rig to use this amplifier. It turns out this is fairly simple to do if you are happy working with the small SMT components.

From the schematic the mod was as follows…
- Cut the track leading from C137 to L44. this disconnects one end of L44 from the original mic signal.
- Fit a link from the disconnected end of L44 to the collector of Q17 the output of the Vox amplifier.
If left like this the mic gain is actually now too high and the rig produces full deviation when speaking from several feet away. In fact the Vox amplifier limits if you talk too close to the rig.
To fix this this, the gain of the Vox amplifier needs to be reduced. Unfortunately this means that the Vox will no longer work but I doubt that many people use it anyway so I don’t see it as much of a loss.
To reduce the gain of the Vox amplifier a 470 ohm resistor needs to be inserted between Q17 emitter and ground. This can be done by cutting the earth track adjacent to Q17 emitter and soldering a 470 ohm surface mount resistor across the cut.
After doing these mods my UV-5R now sounds just like all my other rigs. Good fully deviated audio when talking about 6 inches from the mic.
The low/high deviation setting on the rig now works as intended. High gives 5 KHz deviation for 25KHz channels and low gives 2.5 KHz for 12.5KHz channels.

I had expressed some concern at leaving the output of Q17 (Vox transistor) connected to the Vox circuit, but Colin didn’t seem too worried about this.  He’s tried it and has heard the results, so I’m inclined to believe him.  His response was:

The remaining connection to the vox circuit doesn’t seem to cause any problems. The vox does still work but because of the reduced gain it needs a very loud shout to activate it!  I did try leaving the vox amplifier as it was and reducing the mod signal with a potential divider but when talking loudly the vox amp was limiting and introducing a lot of distortion.

So – go forth and modulate!

Many thanks to Colin G4EML for his work and for sharing this with us!

Now, the images – Click for full size:

This is a hardware modification for the Baofeng UV-5R.  It deals with surface mount components of 0603 and 0402 size and you will need a very small soldering iron tip, preferably with temperature control, unless you’re a soldering jedi.  If you don’t feel comfortable in disassembling and/or modifying your radio, then don’t do it.  I can’t be held responsible for any damages.


  1. Remove the battery.
  2. Remove the belt clip, if installed.
  3. Pull off the volume knob.
  4. Remove the nut around the volume potentiometer.
  5. Remove the nut around the antenna connector.
  6. Remove the two screws on the back, near the battery release switch. Careful – there is a spring under it.
  7. Remove the two screws on the back, near the bottom of the radio.
  8. Pry up the bottom of the radio where you removed the screws in step 7, about 5mm or so.
  9. Pull the back section of the radio down and up to remove it from the front case, being careful of the speaker wires and button material.
  10. Desolder the speaker wires.
  11. Flip the board over and remove the screws attaching the PCB to the metal shield body.  There are two screws under the display.  See #14.
  12. Remove the two screws either side of the antenna connector body.
  13. Remove the screw down by the flashlight LED – this secures the battery connector.
  14. Remove the two screws holding the display onto the PCB and rotate it upwards, removing it from the PCB.  Try to keep it in one piece.
  15. Remove the final two screws from the PCB (under the removed display).
  16. Locate the battery connector on the back side of the radio and pull it straight out.  Don’t bend the pins.
  17. Lift the volume control side of the PCB off the shield first – this will allow the antenna connector to come out without needing to desolder it.
  18. Flip the PCB over and you’re ready to begin the modification(s). 


Is pretty much the reverse of disassembly, with the exception of the display.  if you don’t get the rubber conductors and display and pads all lined up the way they were, the display will have segments missing, or not work at all.  I’ve found it easier to attach the display module to the PCB with the two screws on its bottom side, but not fully tighten them.  Then use a small screwdriver or large pin to pry out the clips at the top side of the display module and push down on the top side of the display module so they clip over the protrusions on the PCB, securing it.  It might be a good idea to hold the battery on the contacts to ensure the display is aligned and working correctly before reassembling more of the radio.
Getting the radio back into the front case can be a bit of a pain in the backside too.  The side buttons (PTT, MONI, CALL) get caught up a lot and will probably take you a few re-seats to get right.  I know it takes me a couple of attempts each time to get it aligned correctly.