Kenwood TM-V71

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The Kenwood TM-V71 Mobile Radio

At my QTH I can barely make it to the local APRS digipeater from my Yaesu FT1DR walkie using 144.390Mhz. The local iGate shut down so that left me with no APRS coverage (other than my phone) while taking the dog for a walk 🙁 What to do? Well, I haven’t been very active on FM voice lately. My  walkie can use APRS on any frequency – even UHF – so I thought I thought I’d press an old TM-732 into service as a cross band repeater (5 watts). Low and behold, this worked!

Sort of. It digipeats about 50% of the packets. Oh well, there’s lots of packets right? It works pretty good. Today I thought, “hmm. I wonder if my TM-V71 would work better?”. So I tried it. Yes, it works better. Much better. About 90%+ are passed now. And an extra bonus, my TM-732 was kind of bonky on UHF receive anyway and my walkie’s squawk range is 30% more! Need to send a text or email? Forgot your phone? No problem, APRS is there!

I discovered that 440.390Mhz is the UHF APRS frequency so I’m using that and ID’ing every 10 minutes on the UHF frequency using Morse at 20 WPM. I use a computer to squawk my ID (a STATUS really) over the APRS channel to be legal.

If you’re looking for a low cost solution to an APRS “extender”, this might be the way to go for you. The only issue is squawking on UHF. But, if you’re using a TinyTracker and an external radio, just swap out the VHF radio for a UHF radio – or use BOTH 🙂 – and Bob’s yer Uncle.

 

EchoIRLP

To those that don’t know what IRLP and Echolink are, here’s a brief(ish) explanation. They are both ways to link repeaters but they have significant differences.

IRLP (Internet Radio Linking Project)

Remote IRLP nodes (generally repeaters) are accessed from your local node (generally a repeater) by entering a 4 digit DTMF code. Some nodes require a “prefix” often an asterisk ‘*’ or pound ‘#’ although some use ABC or D and some don’t use ANY prefix. Our local node requires TWO asterisks due to technical issues mostly.

Other connection options include “reflectors” which allow several nodes to be connected together – like a party line 🙂 Some reflectors have 50 or more connected repeaters and some only have two or three.

Echolink

Echolink is a bit more flexible. Echolink nodes can be accessed through RF nodes (either a repeater or a simplex channel) like IRLP but also via a computer or smart device – cell phone or tablet. You can also start up your own Echolink node by downloading the software for free and using a link radio pointed to either a simplex channel or a repeater. Nodes can also be connected to “conferences” (like an IRLP reflector).

To use an RF node you enter a 5 or 6 digit DTMF code exactly like IRLP – often with a prefix as well. To access a node through a computer (or smart device), you’re given a list of available active nodes to choose from (this list is very big). The nice thing about using Echolink via a smart device/computer is you can access your local Echolink node from anywhere in the world where there is internet access!

EchoIRLP

Some repeaters have both IRLP AND Echolink available. To initiate an IRLP call, one enters a prefix and the node number and to initiate an Echolink call, one enters a different prefix before the node number. This is so the node computer can distinguish between the two.

Summary

  • IRLP can be accessed by RF (radio) only.
  • IRLP uses special hardware/software (proprietary)
  • Echolink can be accessed through RF links or computers/smartphones using free software.
  • Echolink uses free Windows® software for both user and sysop nodes.
  • For the most part, IRLP nodes can only be accessed by other IRLP nodes and Echolink nodes can only be accessed by other Echolink nodes. There are some “gateway” reflectors/conferences that accept connections from both.
  • Both systems use DTMF codes to link. IRLP generally uses “73” to unlink. Echolink nodes often use “73” although they often use something else.

Hope that helps 🙂

Raspberry Pi

Sounds yummy eh? I finally got the proper GPIO gear (basically, a breakout box) for my Pi B+ and wow. I satrted out like everyone flashing an LED. Had some issues getting that to work out of the hop but eventually realized the header wasn’t pressed in firmly enough. Doh!

After getting the LED to flash, I of course, had to elaborate on that right away. Started with flashing TWO LED’s then decided, “hey, why not flash FOUR LED’s in a binary counter fashion. Before I even pressed RUN I’d added 4 more LED’s and made an 8 bit binary counter. How fun is that eh?

There you have it. An 8 bit binary counter 🙂

New Age Ham Radio

This is something I posted in my Antenna Building Facebook group:

Although not directly antenna related (well everything ham radio is antenna related, right?), I thought I’d share this. Instead of bucking the internet, what ifhams helped bolster it? We have UHF and SHF and microwave frequencies available to us. Truly a staggering amount of bandwidth. It is sorely underutilized. What if hams could fill in for at least some critical email services? After all, even 9600 baud packet can do about 100 megabytes of traffic per channel in a day. Newer technologies allow operations at 2.4 GHz utilizing small yagis for excellent speeds (1 MBs and higher) over distances of 10km (or less, or more) depending on power and terrain. We have the capabilities to use microwave technology in the 10 GHz range and even much higher than that!

Perhaps instead of arguing about how valid ham radio is today, we can explore other ways to establish an actual presence in our communities and help them like no other agency can in times of need. Passing crutial emails (and other documents) for high priority public services could certainly be called an essential service. Even passing high speed data for the Red Cross or other volunteers could be a make or break service when regular communications go silent – even at 9600 (or even 1200) baud.

And that got me thinking. Instead of using many conflicting digital voice schemes, why not run VoIP on a 2.4 GHz mesh network? Long hauls over internet (city to city for instance) could be established until radio linking can be eventually installed. If your current connection speed is 1200 baud, well, its like having a very slow internet connection. If you’re on a 2.4 GHz connection, you’ll obviously have a faster experience.

There, done. You are assigned an IP sub address on the ham network. Off you go just like having a ham only internet! As long as it was not encrypted (or maybe ‘lightly’ encrypted), everyone could use it for VoIP or data. Now, in an emergency I can still send an email to a loved one or call an emergency agency or tow truck via a Skype like program if I’m broken down and there is no cell service. Repeaters could be just another IP address and I could connect to any repeater – or groups of repeaters simultaneously anywhere in the world – at any time. Or other hams. Or run a remote control program on my HF rig at the home QTH. We could be video chatting RIGHT NOW!

All via ham radio. And all legal. And low monthly fees. Nice huh?

Obviously there will be bandwidth issues. And it won’t be perfect. But if it caught on, and high speed microwave links established, with some computer power it could support quite a few simultaneous users. And wouldn’t the iPhone kids be jealous.

DMR Bitchin’

On the DMR Facebook page a member asks this: “Can anyone tell me if the DR3000 can act as a dual mode repeater?”. In essence, can the repeater be set up to pass digital as well as analog? Another member answers: “Yes it can but i think dmr-marc frown on dual mode and deny access to their network.”. Yep. It’s true! The DMR-MARC network does not allow hams (who are by nature experimenters) to access the system with anything but Moto protocols. Ridiculous.

My comment:

One of the biggest drawbacks to DMR-MARC network is this one issue. In the analog world (or most ham environments), if we want to exchange data/voice to other repeaters by fairy princesses (as long as they are licensed amateurs of course) it’s allowed. Where does the DMR-MARC network get off not allowing hams to experiment? In fact, if dual mode WAS allowed, DMR-MARC would be our clubs system of choice and would allow clubs everywhere to adopt it.

This “no analog on the system” would/should certainly be the case in the commercial world (which DMR was designed for) but I see no reason to disallow it in the ham environment.

Oh well.

‘Nuff said.

EchoStation

I was looking for announcement software for the 146.680 repeater. I currently have EchoLink running on my desktop and connected to my radio. This seems to work quite well but, there is no way to make EchoLink do announcements. So, after looking up EchoStation, and actually trying it out, I paid the big dollars ($19) because it is one of the few pieces of HAM software that actually WORKS! Yep, easy to set up, easy to use, etc.

Then I discovered that it’s a bit limited in to what it can announce – only static announcements! Jeez, I need it to announce the time and stuff and there was no way it would do this. I discovered that it uses separate .txt files to hold the announcements in. SO, I fired up VB6 and made a form and some timers and PRESTO. It now does: current time, weather, weather alerts, club announcements, random stuff at 1/4 hours and more. And, it’s only “slightly” cumbersome.

Since EchoStation is $19, I figure I can charge $5 for my add-on and maybe make a little cash. I do use EchoStation as a DTMF decoder (that beats the module I was going to buy for $127) so that’s a savings of over $100. And EchoStation also includes an “auto patch” (make phone calls over the repeater) feature so that’s a nice bonus. All in all, a pretty good deal.

VE3KCR Update

VE3KCR (147.120+ 100hzPL) now spans over 16,000 square kilometers – that’s about 4 MILLION acres! How much does YOUR repeater cover? Hmm?? Yes, I’m bragging but hey, it’s my prerogative. There are some areas that experience a little hetrodyning but for a non-GPS locked system, it’s not as bad as you’d think. What we’ve done is have the TX sites service “major” population centers with some of the not so populated areas in the hetrodyne areas. And, we added a non standard offset re-broadcaster in Chatham so there’s no hetrodyning anymore if one uses that repeater. So far, so good.

So, 146.680- noPL works as always – excellent. 145.190- noPL is also working excellent as is th UHF machine 444.325+ (250.3hzPL for IRLP). In fact, all of these repeaters have been “reset” so there’s a minimum of  ID’ing, and status reports in morse code. YAY!

Enjoy!

 

VE3KCR

Yesterday, the electronics package was installed at the North Chatham Site. This repeater is a full TX/RX unit tied into the simulcast system. A quick range test (a drive to Sarnia) reveals solid mobile coverage up to Sarnia. We were very pleased at the excellent signal at 35km away. However, this test made it abundantly clear that another cavity filter is required for the RX part – but we sort of knew that. It does tend to de-sense itself and luckily, our RX site situated around 38km away was taking up the slack for receive duty. It is an excellent RX site. However, H/T coverage is now possible in Wallaceburg.

So, after some tweaking (cavity filter, setting TX levels on the other sites, etc) it will work most excellent 🙂

 

CKARC Strikes Again!

Yesterday, May 10 / 2014, a group of hams from the Chatham-Kent Amateur Radio Club installed yet another repeater in the Chatham-Kent area. This site is called the North Chatham Site and should give coverage where no coverage has been before! Upon completion, it is expected to give excellent results into nearly Sarnia to the north, Florence to the east, New Baltimore, MI to the west and possibly the south shore of Lake St. Clair to the south. Combined with the other two (three?) sites, our goal of blanketing south-western Ontario with a single repeater frequency pair will be *that* much closer.

Hats off to those who participated: VE3KNI, VE3OEN, VA3TWT, VE3LFD, VE3RHV, VE3MUN and VE3UGG. Outstanding job by all. I don’t think we will have as many pictures as the East Chatham Site but believe me when I say it was another extremely professional job! All antennas in place and feed line run. All that’s left is the electronics and some additional “inside” work. Hopefully this can be accomplished by the end of next week (or earlier) and we will have a “full service” repeater linked to the simulcast system. Pretty amazing.

NOTE: Due to the fact that hams need to build and design towers, cases, brackets (and a myriad of other things) they (over the whole) do exceptional work not only in electronics but also in machining, carpentry, design and construction of nearly anything. Most hams are very knowledgable in many areas and highly ingenious (and cheap). And, in most any group of hams, you will be able to come up with virtually any sort of odds and ends of parts and materials. Just keep that in mind if there ever is a SHTF scenario!

 


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