Mobile hamsticks as a portable antenna

Every year in April, on International Amateur Radio Day, I try not to miss an opportunity to make a few new contacts. Luckily, this year was no exception to the tradition.

However, my options were limited as my present QTH explicitly restricts any aerials, poles, etc.

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Powerwerx SS-30DV switching power supply – RFI hash noise across all HF bands

Continuing rebuilding the shack. Since hamfests are off-limits due to pandemic restrictions opted to buying brand new equipment on a budget.

Bought a new Yaesu FT-891 which while by all means is not a great performer is a portable and a budget option for a portable/mobile/base station and could be a good choice of a Field Day radio.

HRO had it on sale and also listed Powerwerx SS-30DV as a recommended accessory PSU among slightly more expensive Yaesu FP-1023 (also switching type aka rebranded Samlex SEC-1223) and a more expensive linear Yaesu FP-1030A.

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Staying connected with ZUMSPOT hotspot

Could not miss a good sale on and bought a Zumspot w/1.3″ OLED kit for the shack. I also bought an acrylic case for it.


It took more time to find a small screwdriver than putting the kit together. Basically, you just need to put 4 tiny bolts (included) through the holes in the case and the Pi board, add spacers, and then insert the radio board (with the antenna) into Pi’s GPIO connector:


Took less than 5 minutes altogether to assemble:


The SD card included with the board had Pi-Star software installed on it which saved time downloading and flashing the card.

It took a bit longer to wrap a head around the software configuration and much longer learning about all the talkgroups / reflectors / etc. though.

Toshen, KE0FHS has put together a good guide covering configuration of the hotspot which was very helpful. Here is a copy, just in case.

Basically, the gadget is a small internet-connected digital repeater located at a comfort of your home. Once you put your WiFi network details in it, your callsign and the operating frequency, you need to figure out which of the digital networks to connect it to.

Presently, it seems the most active ones are:

  • DMR (Brandmeister) talkgroups
  • Yaesu Fusion WiresX
  • D-Star reflectors

Both DMR and D-Star require registration. DMR (Brandmeister) was the easiest to register. The admins approved my registration in less than an hour once I confirmed my email. I am still awaiting for my D-Star registration after 2 weeks I submitted it….

You need a matching handheld in order to operate these digital modes since audio encoding/decoding is performed by the handheld hardware / firmware.

Actually, there are software codecs that work with DMR and Yaesu Fusion standards but not with D-Star (due to license restrictions).

As a result, you need a D-Star HT to use D-Star reflectors. At the same time, you can use Yaesu Fusion radio to operate both Yaesu Fusion and DMR networks because they both use the same newer codec for audio encoding/decoding allowing cross-network bridging of talkgroups.

Presently, I am using Yaesu FT-70DR digital dual-band radio from HRO for accessing DMR talkgroups via the hotspot using YSF-to-DMR functionality.


The closest real world analogy to this hotspot technology is a simplex VOIP conference call with the last mile delivered over a radio link. Basically, it’s good ole Echolink with an HT instead of a headset. The medium for communication is the internet – not ionosphere, making communication reliable and simple (as long as the internet is available).

The talkgroups (DMR) / reflectors (D-Star) are a digital analog of a dedicated talking radio frequency. They seem to be mainly grouped by a geographical location. Some link several repeaters together. Some are special purpose: e.g. SKYWARN, etc.

Given the decline in a number of operational repeaters and aging of the hams, these little hotspots provide an affordable option to communicate with fellow hams without a challenge and expense of HF gear and antennas. I dialed my Yaesu Fusion radio to DMR talkgroup TG9 (World talkgroup) and it’s busy with hams chatting from all over the world.

It’s amazing how technology erases artificial borders and makes this world a smaller and a better place.


Thank you Texan friends

They say ‘everything is bigger in Texas’. That also applies to the hearts of Texans.
Thank you for helping us getting back to (new) normalcy and for your compassion, integrity and keen friendship.



Apologies for the extended absence. As some of you know, the last 2 years I was working hard at work while rebuilding a new QTH on a tropical island investing all my spare time and resources in it.

Ironically, a week after all the hard work was finished, hurricane Dorian came along and destroyed our QTH and most of the island with 185mph+ winds and 11 feet of storm surge taking hundreds of lives and leaving little behind. All the hard work, gear, personal items, everything, got soaked or carried away by the ocean and whatever survived, got carried away by looters.

Thankfully, I left the island a few days before the storm hit. Whatever was in my carry-on bag with me are the few possessions that survived. Unfortunately, ham radio gear wasn’t.


It will take years (if not a decade) for the life on the island to become normal again (if ever). The current goal is to find a new QTH, regroup, and try to rebuild our lives again.


QRV again

It was almost a year away from ham radio due to work commitments but today I finally managed to take a day off and enjoy some QRP mobile work while driving to Kennedy Space Centre to see ULA launch to ISS. And what a day it was!

On the way to Cape Canaveral, while driving on I95 and checking, I noticed John K2ZA driving a few miles behind me. When he got closer, I called him on 146.520 and he responded instantly. Then, W4UDP also joined the chat from his QTH and we had a great small group until we drove too far away from him. Thank you for your great company, gentlemen!

Then, on the way back from Cape Canaveral, I put my trusty MFJ-1620 7′ long fibreglass 20m hamstick whip on the roof and Yaesu FT-817ND on the passenger seat, and started calling CQ using 5 watts.

image1 (3)

Except later I discovered that it was actually 2.5 watts (!) but nevertheless that was sufficient to complete a short QSO with Virgil N9TMU in Illinois who were about 1,000 miles away as I was driving just south of Vero Beach, FL on I95 which made it almost 2,500 miles per watt!

Then I realized that my power output was set to 2.5 watts only… Switched it to proper 5W and started calling CQ on 14.061:

Screen Shot 2017-04-18 at 9.41.10 PM

Much better! Doubling the power helped and the RST reports I received have improved.

More great Qs followed: two on CW – K3SEW, VE3EYI, and two nice Qs on SSB: Christian FG5DHF in Guadeloupe (1380 miles), and Christopher W8/SP4RF (?) in Michigan.

Thank you all for your patience. It is fascinating how far a little power and great operator’s skills can go when operating QRP.

I hope, I wrote down the callsigns correctly – it was challenging to make notes while driving and keeping eyes on the road!! All Qs are now in QRZ.COM logbook.

Very 73’s!
DE Paul WA4PAW / M / QRP



ARRL Field Day is in 2 weeks

As the ARRL Field Day is quickly approaching, I signed up as an operator for the night shift for Davie/Cooper ARC.

The club is planning to have 2 HF operating stations, plus a VHF (2m/6m) and a GOTA stations at Markham park in Broward county.


Most likely will be working on 40m – CW + SSB, logging QSOs with SQIRL logging software.

Stop by to say hi, or look for NA4DC on the bands on June 25th!



Bluetooth PSK31/WSJT/Digital interface for Yaesu FT817 (and a tablet/PC)

I used a bluetooth CAT control with my Yaesu FT817 for quite awhile ($14 on ebay) and was generally happy with it. There is a small lag but one can get used to it. The advantage is no wires between a laptop and transceiver. Also, I could use my HP Stream tablet with it (Win 8) this way.

Given this success, I entertained an idea of making a digital (soundcard) interface wireless too. As the connection would be simplex and mono (1 channel), a regular bluetooth phone headset seemed up to the job.

I happened to have one laying around without much use so the first step was to prove the concept which was very easy. Once paired with the laptop / tablet, the headset became available as a soundcard in HRD DM780 settings. I tried sending some RTTY to it and it worked. I guess now I understand what Alexander Graham Bell felt like when his first phone worked (hi hi).

However, receiving (listening) from the headset did not work. After some googling, I found a hint – set bluetooth headset soundcard as a Default device in the Control Panel -> Sound -> Recording Devices settings. That helped right away so the next step was wiring the headset to the transceiver.

After disassembling the headset, I removed existing battery, speaker and mic and soldered new thin wires to the connecting pads.

Headset with wires


For TX (audio out) – I added a 1:25 resistive divider to decrease the output voltage off the speaker wires and to match the voltage requirements of Yaesu; and soldered the speakers wires to it. For RX (audio in), I needed to match Yaesu output to the headset mic. After some experimentation, a combination of two SMD capacitors to both pins and a small resistor in series to avoid overloading and to provide DC isolation finally worked.

Finally, I added a new bigger OEM Li-Ion battery (insulated with black tape) and a USB charger PCB with a switch to improve on portable operation time of the headset.

Li-Ion battery with a charger PCB

The headset, battery, charger, and the existing CAT BT control PCB all managed to fit into a small plastic enclosure. Some hot glue helped to secure them in place.

The boards sit on top of the battery / charger; to isolate the layer I cut a small sheet off a thick polyethylene water jug.


The enclosure is secured with two small strips of a velcro tape. The battery can be charged via a USB connector; the switch turns on/off the bluetooth headset.


The PTT is controlled by the software via the CAT control. Now to chase DX with WSJT QRP mode!



Just got an email this morning from FCC about approved allocation of a new callsign as per my application – WA4PAW.

Obtaining US callsign / license

Had a great time stopping by the Broward ARC meeting in Ft.Lauderdale last night; met a great bunch of very friendly hams there.

Even though reciprocal agreements between US & Canada allow VE3 hams to operate, I though it may be a good idea to attempt a US amateur license exam and obtain a callsign from FCC given the opportunity. So I showed up at 6:30pm at the club, and then wrote and successfully passed both Technician and General exams.

Each exam was only 35 multiple-choice questions (fairly easy ones compared to the Canadian Basic exam). To pass, 26 correct answers were required. There was one question I didn’t have answer for – how many hams are required by FCC to open a club. I guessed 3 and the right answer was 4.

There was not much time left to attempt the final Extra exam this time, plus I was not preparing for it, so will probably give it a try next time.

Now having the exam papers submitted to FCC, a random sequential callsign is to be allocated within 15 days.

73 for now!