Author Archives: N3BBQ

VPN Setup

This is mainly for the BAC contest this weekend.

Download (64bit windows):
Download (32bit windows):
Install that as administrator, then download and copy the contents of this zip file to C:\Program Files\OpenVPN\config

VPN Config:

This should give you an icon that will have Connect as an option, which will ask for a username (your callsign) and the password (which we will give you on IRC). This will then assign you a 10.8.0.x address.

N1MM+ Setup

  1. Install N1MM+ and run it to update to latest version.
  2. Go to Tools -> Update wl_cty.dat (internet) and update your country file.
  3. Close N1MM+
  4. Download the BAC UDC file from here and place in your Documents/N1MM+ Logger/UserDefinedContests directory
  5. Download the KA1DS N1MM+ database from here and place in your Documents/N1MM+ Logger/Databases directory
  6. Launch N1MM.
  7. File -> Open Database -> KA1DS database file you saved previously.
  8. File -> New Log in Database KA1DS
  9. In N1MM+ New Log Dialog Box
    1. WA1J_BAC
    2. Operator: MULTI-MULTI
    3. Band: ALL
    4. Power: HIGH
    5. Mode: SSB
    6. Overlay: N/A
    7. Sent Exchange: W
    8. Operators: <Your Call>
    9. <OK>
  10. You should have N1MM+ running now with a Callsign, a serial box (not editable) and a Booze box.
  11. Time to get networking started!
    1. Turn off windows firewall.  You’re behind NAT so dont worry.  N1MM needs to talk to ports that windows firewall doesnt like on the WAN side.
    2. Windows -> Network Status.  A box should appear saying “Click to start networking”.  Click the box in the window.  Stations should be appearing if the VPN is working as it should.  Dont worry if your IP isn’t on the same subnet as everyone elses.
    3. Window -> Info (your chat/irc log)
    4. Ctrl-E to open up chat window where you can type lewd things to people.

DC Powered Shack PC

Last week I was thinking about my new house and the awesome shack I could build in one of its many empty rooms.  All the pretty equipment I could buy started flowing through my head and our IRC channel.  Since the house is going to have a standby generator, I was thinking about a UPS for the desktop computers in the shack.  Then the idea came to me, why not run a DC powered computer?  Well, that sounded like a great idea!

Through my research, I found the Intel NUC machines.  I knew we used these at our office for our 40+ conference rooms, but I didn’t think about their power bricks for power.  After some researched, I found a few models that have their specs for 12V-19V.  These models are the NUC5i5RYK and NUC5i5RYH.  They are Core i5 processors with up to 16GB ram and m.2 SSD drives.  The K model only allows the m.2 SSD drive, while the H model allows a m.2 SSD drive AND a 2.5″ SSD SATA drive.  They are a case difference between them (take a look, you will see H is taller).

nuc_powerbrick I got a NUC5i5RYK for testing, and put 16GB (2x 8gb So-dimm) memory and a 80gb m.2 SSD drive into it.  I installed Linux Mint for testing, but these will run windows 7 and 10 without problem.  I did a quick test on the machine to make sure everything was working, then I cut the cable off the power brick.  This is where the first surprise showed up.  The power supply cable is a simple coax type cable.  It had a foam dielectric, with a non braided shield and a multi threaded conductor center line.  This was fairly easy to change into Anderson Powerpole connectors with a little bit of heat shrink.

nuc_idle_wattageOnce I got it setup correctly with the powerpoles, I powered the NUC back up with my linear power supply.  It powered up nicely without any problems.  During bootup, my inline meter said it was pulling up to 23 watts, but when it got to the desktop screen (within about 10 seconds of total poweron), it was at its idle power usage of 8 watts.

20150914_180119I fired up Firefox on the desktop and started up a HD youtube video in full screen.  This gave me a power rating of around 20 watts while watching videos.  I couldn’t easily get it to pull more than this during my tests.

Since it was running off the power supply fine, I decided to put it on a small SLB I had laying around (that wasn’t fully charged).  This is when I decided to start taking pictures of the usage, so the voltage looks lower than my power supply was giving out.

20150914_191902It ran fine from 13.8V down to 9V.  Once it dropped below 9V, the NUC turned off.  Here you can see that it was running 9.38V and not having any issues.

So, what does this get us?  A dual screen capable PC that will run straight off your DC power distribution.  No external UPS needed if you already have a battery system for the shack for emergency power.  There is also no aidsy switched power supply wall warts to make noise in our local areas.  Next up?  Trying to find a good 12V monitor.

How to build a tunable repeater on the cheap (Part 3)

In the last post, we got the COR circuit working between the Baofeng and the repeater controller.  In this post, we will continue with wiring up the Baofeng to the input side of the repeater and getting wiring looked at for output to the D710.

Byonics htkp Cable Diagram
I am using the Byonics HTKP series HT cabling for getting audio out of the Baofeng UV-5R, and providing power to the repeater.  In this case, I have the Powerpole connector on the cable.  I have a DB9 female connector with pins 5, 6 and 7 passed through (the rest are unconnected).  Pin 5 is the speaker audio, Pin 6 is Ground (linked between the shield on the headphone and the negative line on the powerpole), and Pin 7 is the +7 to +18V positive from power (red on the power pole).

The pinout on the ID-O-Matic IV has the pinouts as follows:

PIN 1 Ground
PIN 2 Power Input (6 to 20V)
PIN 3 PTT Out (keys the transmitter in FM repeater applications)
PIN 4 CW Out (on/off keyed Morse code output, NOT audio)
PIN 5 Beacon Indicator output (active when beacon is being transmitted)
PIN 6 Reset (ground to reset the ID-O-Matic IV)
PIN 7 COR Input
PIN 8 Receiver audio input
PIN 9 ID Indicator (active when Morse ID is being transmitted)
PIN 10 ALT MSG input (selects the alternate CW ID transmitted)
PIN 11 Audio Out (Morse ID and Tone output)

I put a 1K resistor between the pin 2 and 7 on the ID-O-Matic, then brought in the COR line from the Baofeng to PIN 7.  The ID-O-Matic is now setup to receive power and audio from the Baofeng and Byonics cable.

Now, to get audio out of the repeater to the D710 is pretty easy.  The D710 has a documented information about its microphone port.  It is RJ45, which makes it pretty easy to come up with a cable for.

On the Kenwood RJ45 connector, Pin3 is Ground, Pin4 is PTT, Pin5 is Mic Ground, Pin6 is Microphone input.  Output from other audio sources should have a register on the mic line of the value 470.  It should also be shunted to Pin5 via a resistor of value 3.9.  I get these values from the Sky Commander manual for the D710G.  With this fairly simple wiring, we have the following:

PIN 11 (Audio Out) PIN 6 (MIC)
PIN 12 (Ground) PIN 5 (Mic Ground)

Once these are all hooked up, the repeater should work.  The kenwood will key up when the green LED turns on with the baofeng.

I ended up moving all of this to a board with solder on plug connections from Sparkfun for the RJ45 and DB9 Connectors I am using.  Here is the board while being created:

Radio interface module for ID-O-MATIC by N3BBQ

This allows me to put the repeater in a small box and supply power / control lines to the radios via standard connectors which are already on my cables.

Stay tuned for information about duplexers in Part 4.

How to build a tunable repeater on the cheap (Part 2)

In my last post, I went over the basic parts of a repeater, and said the parts I selected for our build.  I will go into the choices further and give some information about getting the baofeng working with a COR output.

The radio I selected was the Baofeng UV-5R.  Its schematics are available online, and I found that the radio only lights up its green RX LED circuit when the PL circuit breaks squelch when using tones (unlike other handsets that show receive, even though they don’t break squelch). This seemed like the perfect place to add a link from the hand held to the controller.


The transistor shunts the circuit to ground (with the battery on the other side) when a signal comes from the radio’s PIC.  So we will have to keep a positive voltage on the COR line with a resistor so that when it shunts to ground, we can have the COR circuit go low when active (ACTIVE-LO polarity on the I/O menu of the ID-O-Matic).

So, I took the UV-5R apart (instructions are already on the web, so I will not duplicate them here), and found where the circuit physically is. It is by the PTT button, and wraps around the VFO-MR orange button.

UV-5R RX Led Circuit

You do NOT need to remove the LCD screen for this mod.  But you should remove the speaker from the board connections, and the case, so you have room to route the wire out.  I drilled a hole in the case on the opposite side (where in front of where the mic/headset plugs are).  I soldered it directly to the bottom of the two transistors (the correct circuit in this case).

Here is when I was testing the circuit before I added a ground between the two (this will be added permanently when I add my Byonics HTK2P cable that will power the controller, and give me the speaker output all at once).

Once I verified that COR was working correctly, I packed it all back into its casing with the cable done in such a way that it could be used in the future.  The Baofeng is now modded to be used as a Receiver radio with the ID-O-Matic.

Stay tuned for more information on how to build a tunable repeater on the cheap!

How to build a tunable repeater on the cheap (Part 1)

I recently set off on a small quest of building an inexpensive same band repeater for portable and special uses where there are no current repeater coverage.  I wanted something low cost, portable, and tunable without special software.

I finally settled on using some parts I already had, and other parts which I could build.  Lets take a look at what the main components of a same band repeater are:

  • Receiver Radio
  • Controller
  • Transmitter Radio
  • Duplexer

Most people know what Receiver and Transmitters are.  This isn’t a repeater that is going to be used much, maybe one weekend a year.  Therefore, I decided to use the Baofeng UV-5R I have as the receiver radio since I will not be transmitting with this radio.  The Baofeng is what I consider a disposable radio, coming in at under $50 most of the time.

For the Controller, I selected the ID-O-Matic IV by Ham Gadgets with the additional Voice Module.  This kit cost me $49.  It does Time Out Timer (keeps the repeater from being keyed up too long), morse ID, and a voice ID.  It has a simple USB (serial) interface to change settings and update firmware.  The only problem with it and the baofeng, is that it requires a COR input to know when the receiver is receiving (and to PTT the transmitter), and the baofengs (and most hand helds) do not have this output.  Also, some controllers deal with the PL codes.  However, we will be using the PL decoder/encoder on our radios, so these can easily be changed in the field.

The Transmitting radio is where you would want to spend money.  I am using a mobile Kenwood TM-D710G as my transmitter radio.  Normally, this radio can do crossband repeating by itself (and even do ID when in this mode), but we are going to just be using 1 side of the radio for this project.

Finally, the all important Duplexer.  This is the hardest part to come by cheaply.  The Duplexer / Cavity filters are important so you can use one antenna between both antennas, but not have the transmitter desensitize the receiver.  These need to be tuned, so they only allow the two frequencies you want out of the duplexer for each radio.  Cheaper duplexers you can find on Ebay from china can work, but you must make sure they are tuned correctly!.  I selected a Chinese made UHF 6cavity duplexer, and requested them to tune it to specific frequencies for me.  This included a +5Mhz offset, like normal repeaters use.

Of course, there are other things that will need to be looked at, like power, and maybe a GPS unit to supply time to the controller, but those are generally things that you can build / pickup cheap locally and use for other projects too.

In Part II, I will be writing about adding the COR circuit to the Baofeng UV-5R, and getting the repeater wired up to the receiver correctly.

How to build a tunable repeater on the cheap (Part 2)


JT65 via RemoteHamRadio.Com (Browser based)

Today, I was bored and decided (and it was suggested to me) to try to get a JT65 QSO via  I was able to get this done and was able to log Italy tonight with it!

First JT65 QSO

It shouldn’t take too long to do this for anybody else.  This was using the $99/year + station fees subscription (RemoteDX) there at RHR.

The needed tools (how I did it) are:

  • Virtual Audio Cable (Must purchase it or it will spew Trial over the air while transmitting)
  • WSJT-X
  • Chrome Browser
  • RHR Subscription

First thing first, install Virtual Audio Cable (VAC).  Then go into the Virtual Audio Cable Control Panel and setup two virtual cables like so:


This will get you the cables setup the way I had them working.  The main difference is Cable #2 has MIC AND Line selected instead of just Line.


Next, goto the playback devices in your OS (right click speaker in task bar and do Playback Devices on windows 8).  You will want to set Line 1 as your Default Device.  Also, make sure you have all windows sounds off, and do not have any other applications that will do sound enabled.  This isn’t such a bad thing, as Line 1 is going INTO your JT65 application, not being sent out to the radio, so it will just mess up decodes if you dont.


Next, startup WSJT-X, and go into settings.  Add your callsign if needed, and change the grid square to the radio site’s grid.  This is to make sure everyone is seeing you as coming from the remote site’s location and not your home QTH.  Radio should be set to NONE (you can’t remote control RemoteDX at this point), then go into Audio.  Set Input to Line 1, and Output to Line 2.  When you hit OK, you should not get any errors.  If you do, I am not sure what caused this.  I had to change the windows default device back to normal then do these, then windows default playback device back to Line 1.  Your mileage may change.

Finally, on the Remote Ham radio console, hit troubleshoot audio, and let it have access to your microphone.  Then click the little camera at the top right of the address bar, and change the Microphone to Line 2 like below:

This will require you to restart chrome after you do that change.  Once you do, you can test again and see if it is picking up the Tune tone from WSJT-X.


To hear either virtual cable out your normal speakers, you can use the audio repeater program:

Just select the virtual cable as Wave In, and your normally default output device on Wave Out.  Then push start.  This will let you troubleshoot the setup without changing things around much.


I then got onto a station, set the frequency to the correct frequency for the band I wanted to use, and let it decode a few minutes worth of audio.  It should be pretty obvious if it is working or not in the waterfall.  The waterfall wont look like a normal waterfall, it will probably have tiny horizontal lines on it.  That will be fine.  It should start decoding after your first full cycle.

To transmit, you will have to hold down the Push To Talk button on the web panel at about :58 seconds to let the latency catch up.  When WSJT-X shows me that it has stopped transmitting, I let go of the PTT.

Currently it isn’t as hands off as a local radio with CAT control, but who knows what the future could hold?