Tuesday, March 29, 2016

Techy Tuesday - Hands on With the CountyComm GP-5/SSB

I first encountered this interesting little brick of a radio in an article at Brushbeater, linked to by Western Rifle Shooters Association.  The article was on signals intelligence, and using various radios to monitor activities in your area.  I soon came to realize this radio was becoming a prepper's favorite radio; the one radio everyone talked about having for when it has truly hit the fan.  From my perspective, I was interested in it because I just hadn't seen a portable receiver with specifications like this.  The first unusual part is that it receives Single Sideband, and I just haven't seen SSB in a receiver this low in cost before.  The second unusual part is that it has an unusual, modern, design architecture that you just don't typically see in low end radios. 

Single sideband or SSB is a kind of modulation (which just means putting information onto a radio signal) that's used throughout radio. If you tune across an SSB station with an AM radio, the best you can do is get a “Donald Duck” kind of sound that's unintelligible. Virtually everyone in the shortwave spectrum uses SSB except the big broadcasters; that means local hams, marine radios, aviation and more are going to be in SSB.  Any military comms that are "in the open" will be in SSB.  There are two "flavors" of SSB, Upper and Lower sideband (USB/LSB); most of the commercial radios use USB but hams generally use LSB below 14 MHz.  Besides that, it tunes from 150 kHz (Very Low Frequency, VLF, which is more common in other parts of the world than North America) to 30.0 MHz, including the AM broadcast band (BCB) and adds the FM BCB.  
I did some reading on these radios and found that they were reportedly originally left over from a contract that CountyComm had with the US Government, and if you look them up, CountyComm says this is their Government Products Group, and lists their Federal Supplier Cage Code.  The manual says Government Products Group on the cover.  The story is that some agencies wanted SHTF radios for employees in other countries.  Someone in the agencies could program the memories for the users, and if they had to use the radios, everyone would have the same set of frequencies to listen to.  It appears that CountyComm had a special order with Tecsun, who produced a special version of one of their designs for this contract.  The radio uses an architecture called direct conversion with an image reject mixer, and is a low parts count wonder.  

I decided that the $80 price tag wasn't too much, in the interest of science! you know, and got one.  It's an impressive little radio, but it can be hard to use.  I've never seen a radio that cried out for a numeric keypad as much as this one does, but when you first get it in your hands, it seems the only way to get where you want to tune to is by tuning the thumbwheel on the right side.  Potentially, for a long, long time.  Thankfully, they give you a few ways around this.  

The first way around it is what CountyComm calls Easy Tuning Mode, or ETM.  Let's say you turn it on and hit the MW button (for Medium Wave - the AM BCB).  Press ETM and hang on; the radio will scan the entire band and store the frequencies where it heard something.  Now you just turn through those memories with the tuning knob.  Do the same thing with the FM band, and you get a second bank of memories.  Every time you go back to MW or FM, those memories will be there.  Going on vacation?  Just re-scan when you get there and the new stations will be saved.  When you get home, re-scan and it will find your same stations. 
The same basic system works for the SW bands.  The control panel (above) has two buttons for the SW Bands, an up and down arrow.  This will take you through all the allocated SW bands.  You can choose a SW BCB by pressing one of the SW up or down arrows and then hit ETM.  This time you'll have to wait a while, but after a few minutes you'll hear audio again and the radio will be active.  Now you can tune through the ETM memories with the thumbwheel and every SW station it heard will be there.  Note that the ETM memories don't override each other and your SW stations won't replace the AM or FM stations.  There are separate banks for AM, FM and SW ETM, and there are separate banks for other user-entered memories for those three services.  100 for AM, 100 for FM and 250 for SW.  In addition, there's another 100 memories for SSB only stations.  When you press USB/LSB briefly, you turn on that mode, and the next time you hit the up or down arrows, you'll go through the ham bands that tune SSB, not the SW BCBs which are in AM. 

How do you find a specific station?  Someone just told you that Radio Australia is on 9580 kHz in the mornings and you've always wanted to hear them.  You could use the ETM, but you don't know if you can hear them at all.  You could always choose the SW band with the up/down arrows, then start tuning with the wheel.  It can still take a long time to find stations in those bands, though, so I've adopted a trick I learned about in a video about the radio.  I sat down one afternoon and started saving entry points roughly every 100 kHz into these SW bands.  Take the 31 meter shortwave band: the charts say that it starts at 9400 kHz and goes to 9900.  I tuned to 9400, pressed MEM, then tuned the wheel up to 9500, pressed MEM, and so on, stopping at 10,000 kHz instead of 9900 (because 10,000 kHz is the time standard station WWV).  Now if I want to listen to Australia on 9580 kHz, I just hit the VF/VM button to go into memory and tune the thumbwheel up to 9600.  Hit VF/VM to go back into manual tuning, and then tune down to 9580.  Of course, I could have gone to 9500 and tuned upwards, but that's much farther than going to the 9600 and tuning down.   This video is a good overview of all that I've talked about here.
All in all, it's an impressive little receiver.  The SSB performance is acceptable, but has some issues; the receiver AGC (automatic gain control) has some problems with SSB, which is pretty common.  Back in December, I proposed a simple test for how well designed the antenna matching circuits are in little receivers like this: while listening to weak SW signal, touch the antenna: if the signal gets louder, the receiver isn't optimized for its antenna.  You made the antenna bigger when you touched it and that helped it pick up more.  If the signal got weaker, the antenna was well-optimized.  This radio fails that test, but to be honest, it's far easier to do that with a radio that tunes a few discrete bands, like the Kaito WRX-911 I mentioned back in December.  CountyComm is aware that the antenna is usually the weak link in a broadband receiver and do two things for you.  First, they have a clip-on wire (about 20', I think) for the antenna.  A metal clip grabs the antenna, and you stretch out the wire as far and as high as you can.  Secondly, they include an AM and VLF antenna that plugs into a socket on top of the radio.  There is a built in AM antenna, but this one improves performance noticeably. 

As for weak points, while it's an impressive performer and I can mitigate not having a numeric keypad somewhat, it still uses that tuning wheel a LOT, and I suspect it as a part that might wear out first.  It desperately wants either a keypad or a computer control bus, but has neither.  It has a USB B connector on it that is used to charge the board batteries (I put NiMH batteries in it - it takes 3), so I plugged it into my PC hoping to hear the Windoze sound that it found new hardware, but no such luck. 


  1. I didn't know it came from a fedgov contract, thanks for pointing that out.

    I agree, it either needs a keypad, or make the USB port be an interface for programming rather than just a battery charge port.

    If they did that, I'd even buy one for the guys who do Chirp, just so they could get it into their list of supported radios.

    As a side note, if you don't need, or understand SSB, you can get pretty much the same Tecsun radio with no SSB through Amazon for about $30.

  2. Funny you should mention Radio Australia, I was just listening to it. Nice concept for a radio, but I prefer something with a proper tuner and big enough for my fat fingers.

    1. It's a bit small, for sure. It's about size of my TV remote control, about an inch longer than my iPhone, and thicker, but narrower. You're likely to lose it under the papers on your desk.

      It's unfair for me to compare it to my bigger, much more expensive rigs, but it's good for its size, and power consumption.

  3. I'm just happy when I can pick up KFYR or KOA or CKOM on the AM radio on the way home from work.
    Used to get some great skipping in between Saskatoon and Winnipeg on holiday drives.
    So, many stations I'd never heard over the air before.
    I'm sure they are all online but that is not the same.
    Takes me back to being a kid.

    1. Oh, yeah. Good memories of lying in bed as 10 or 12 year old, tuning the AM band on my clock radio alarm clock and hearing stations all around the country. Then later, as a 20-something, listening to the AM band while driving somewhere at 4 AM to go fishing.

  4. When my wife and I cruised the Bahamas and Berrys on our cat, I used a Kaito 1103 that could access SSB in order to listen to CARIBWX, The Caribbean Weather Site. Chris (can't recall if I ever heard his last name) put out what was supposedly the best weather reports for the Caribbean, with specialized individual reports for subscribers - which were still helpful for those of us who didn't, but happened to be in the vicinity of the area of which he spoke. At times it was a bit dificult to get a good signal, but it came through loud and clear most of the time, especially if I deployed the long (20'?) antenna wire up onto the rigging.