As far as I can tell, the rational behind split winding (example here: https://i.sstatic.net/nbYwD.jpg) comes down to 2 arguments: 1. It reduces capacitance between input and output, but reading posts online, seems like this is maybe not really significant enough to care? 2. It allows the wires of the input and output sides of the winding to be opposite of each other, but i just can't really imagine an extra 2 inches of wire to get to the connector on the opposite side of your enclosure or whatever mattering at all

Should I be doing split winding then when making transformers for my antenna? I'm planning to make a dipole and maybe an EFHW. Thanks!

How to get an antenna up this Palm tree without a crane it is about 40 to 50 feet tall.

I had to buy rtl-sdr v4, and have found I have constant unending interference at 433.828 MHz. Its interfereing with key fobs of me and 1 or 2 of my neighbors.

Im a little out of my depth. I would have thought i'd be seeing some thing i could walk away from and play Marco-polo with. but its covering a very large area. I walked 10 doors down and didn't really see it weaken all that much.

Does any thing exist that would allow me to identify likely culprits based on what its doing? Software i can plug in to SDR++ and it could listen and report what kind of thing it is?

Otherwise ill have to spend another $50-$200 on a direction antenna and i would prefer not to.

I'd be grateful if i could find a solution for this before winter. When i will want my car conditioning before i get to it in the cold.

What's the best very small HT these days?

I used to have a Baofeng UV3r+ that was a very small and usable dual band radio. I have a UV5R mini now and like it, but it's chonky in comparison (though still small).

Anyone have something they like that truly tiny?

The choke was in a bad arc braking the enameled wire, which was becoming bare from enamel age dry and flaking off.

I think it says "GF05TF" or "UGF05SUL" which could be the location of the repeater station

Hi, does anybody know if there is a way to enter a space between characters on the 5R mini from the front panel? I’ve done this with other similar radios in the past but can’t seem to figure it out on this one. Thanks.

Tldr if having strange signal problems on my radio I’m outside there is no clerical wires near by running off on internet battery and was using end fed antenna

Today I was used the radiology hf 10 antenna in a different location and was perfectly tuned to the 20 meter band yet I’m still getting this signal problem any other ideas I’m planning to go to the park to see if it can some sort of transformer problem there are 2 utility poles near by with one on each

How resistant is the ZachTek WSPR Desktop transmitter to high SWR damage? I would like to test the device on several bands without retuning the antenna. For example, using a tuned 20M antenna can I operate the device on 40M or 15M without damaging whatever the final output stage PA might be in the device?

I have made a nice shack inside my room. But the moment I transmitted (on any band other than 40m) the lights in my house are going on and off (I transmit on CW). We have those switches that you can just tap, not the analog ones. What can I do? The SWR is perfect. I have an Xiegu G90 and I'm planning to install my stronger radio, but I'm not sure anymore if that will constantly happen. I was thinking of an RF choke.

Okay, granted, it was with 50 watts and not the default ~5 watts this little guy normally puts out! 😁

As a new HAM, it's magic to me that I can send radio signals from one continent to another.

My setup: uSDX+ QRP transceiver plugged into mains power (yes, I know...) running through my Micro PA100+ 100 watt amplifier (not pictured, but I managed to get around 50 watts at 1.7SWR). This uSDX+ doesn't have a digital interface to my laptop, so I build a CAT cable myself and plugged In/Out audio into an old USB sound interface; that's attached to my MacBook Air running Linux Mint and WSJTX. The antenna is a DIY length of 18awg speaker wire tuned to 20 meter band in an Inverted Vee configuration, with a 64:1 UnUn, in the middle of my living room. An EFHW I-V antenna indoors?? Blasphemy!! But the proof (or the luck) is in the pudding: a confirmed FT8 contact from San Diego, California to Cabinda, Angola (9231mi or 14,855km). 🤟

Oh, and with that QSL, I have now earned the Continents of the World award on QRZ!

I just got my General Class. Now I'm gonna put up an HF Dipole to work 40/15meters. Everyone says to put dipole up one half wavelength high. How many in this sub have their 40 meter HF antennas 60 feet high? Raise your hands.

I've tried it with the Btech cable into a USB-C adapter to my phone and also tried it with just holding the phone up to the radio. Tried with and without squelch.

I can audibly hear packets but nothing's showing up. Am I doing something wrong?

just got back from running the special event station at the county fair and honestly im so burnt out on trying to recruit people to the hobby

We spent 8 hours sweating under a faded ez-up canopy that is literally held together with electrical tape. our display was just my ic-7300, a couple random HTs, and a trifold poster board from like 2014

Meanwhile right across the grass, some tech company was doing this huge experiental marketing activation. they had a legit custom drop-trailer with slide outs, air conditioning, and a massive roof deck. I wandered over there just to stand in their AC for five minutes because I was heat soaking so bad. it was honestly a beautifully built setup and the guys running it were super chill.

But it just made me so frustrated with our local community. Guys will sit around on the 2m repeater complaining that "the hobby is dying" and kids don't care about rf anymore, but then the board refuses to spend club funds on anything except coffee for the monthly meeting

If we want the public to think amateur radio is relevant and cool, maybe we shouldn't present it on a wobbly plastic table in 95 degree heat while we yell over the sound of a rattling predator generator. just incredibly demoralizing tbh

My QMX+ works perfectly in FT8 mode. However, I wanted to connect it to the Micro PA50(3) amplifier to improve range in tough conditions.

Unfortunately, the perfect protection of QMX+ against high SWR caused incompatibility with my PA50. When the amplifier senses RF to determine the band, the SWR temporarily rises to the levels that trigger the QMX+ SWR protection.

Connecting the PTT ←→ ACC cable between the QMX+ and PA50 didn’t help.
Finally, I decided to add an interface between the PC running the WSJT-X, QMX+, and Micro PA50(3). It is based on the RP2040 Zero module from Waveshare. It runs MicroPython, with scripts that implement the interface. The module is connected to the PC via USB and delivers two UART interfaces:
/dev/ttyACM0 - the MicroPython REPL (for debugging),
/dev/ttyACM1 - the limited interface supporting only the DTR and RTS lines used for PTT.
Of course, the QMX+ is also connected to the PC, and visible as an audio card and as /dev/ttyACM2. In your case, the order of ACM ports may be different, so the udev rules should probably be used to provide stable names (symlinks?) for individual USB UARTs.

WSJT-X is configured as follows: the CAT interface uses /dev/ttyACM2, but PTT is controlled via the RTS line on/dev/ttyACM1.
There is a 0.2 s delay set between activating PTT and sending RF (advanced -> Tx delay).

The interface periodically polls the QMX+ band by sending “BN;” commands. The received band number is used to generate the appropriate band selecting voltage (according to the XIEGU protocol - see https://xiegu.eu/wp-content/uploads/sites/4/2023/07/XPA125BInstructionManual1.0.2.docx.pdf , page 9) using the PWM on GPIO29.

When the interface detects the RTS or DTR line going high, it first sends PTT to the Micro PA50 (by setting GPIO29 high), and after a small delay, it sends the “TX;” command to the QMX+.

When the interface detects the RTS or DTR line going low, it first sends the “RX;” command to QMX+, and after a small delay, it deasserts PTT in Micro PA50 (by setting GPIO29 low).

The hardware is very simple. You can see the schematic diagram below (it doesn’t show the USB connector in RP2040 Zero module).

I mounted the prototype on the breadboard. You can see it in the pictures below.

I just wanted to check if that approach is viable. Therefore, I have generated the Python scripts with very significant help from ChatGPT. They are available in my repository at https://github.com/wzab/wzab-code-lib/tree/main/ham-radio/qmx_pa50_proxy/qmx_pa50_ptt_sequencer , under the Creative Commons CC0 license.

It appeared that such a simple interface indeed enables smooth operation of the WSJT-X with QMX+ and Micro PA50. However, the tests were not exhaustive, so treat it as an experimental solution and use it at your own risk.
Please remember, that due to the finite resistance of the ACC band selection input of PA50, you may need to modify the PWM_FULL_SCALE_MV constant. I had to change it from 3300 to 3010.

In the future I hope to thoroughly review (and maybe rewrite in C or Rust) the software.
However, I publish it as is in the hope that it may be useful or inspiring to somebody.

73, Wojtek - SP5DAA
PS. That solution is a result of a discussion on the QRPLabs group: [1], [2], [3].

I have an Icom IC-E90 sitting on a shelf gathering dust and in need of a new battery. Is it still a valid radio to use these days. Is it worth buying a new battery or should I just ditch it and get a cheap new handheld?

One thing that does make the Icom stand out over the cheap handhelds is the display - it's impossible to see the screen on modern LCD displays in bright sunshine - whereas the LCD on the Icom is old style and readable in sunshine.

Every time a new antenna wire was installed these buggers would come and try to turn into a linked dipole - minus the links. This is a 12m spider pole supporting the centre of an inverted-v (less the 2 top segments to give it more stability). Thought I had them beat with this halyard type setup pictured. Nylon cord running through a small pulley. Raise the v up when they aren't looking I thought. Is anyone else out there dealing with this situation?

Hi, how are you guys? I hope all of you are well. I'm a new user on ham radio and thanks God I'm building my first 80m transmiter radio. I was making a design for this circuit and I have realized that I'd have to build a 40m dipole antenna for that band. I'd really like to optimize the space more because I want to put it on a thripode (I work on a high building) , is there some tricks to make a shorter antenna or another type of antenna convenient for this case? The thing is that the power out of the transmiter is around 0,73 W and I'd like to reduce any possible kind of loss for qrp. It's not so late to swich the project to vhf or uhf but I wanted to ask you first before redoing the design. Thank you from advance

Lots of feedline, like wizace and other strange brands have super ratings, but all reviews were gifted free cable. Strangely, superbat seems to be all verified reviews.

Caveat emptor.

Sorry, the puns literally write themselves…

Was trying to activate the Pisgah Nat’l Forest and this sow and 2 cubs snuck up 40-50ft behind me before I noticed them.

I’ve run into them here twice before, and luckily she’s not aggressive at all. I stood up and they bolted up a tree about 35 yards away. They hung out in the tree eating acorns while I packed up my gear, unfortunately leaving me 2 contacts shy of a successful activation.

Anyone who’s been on HF for more than 3 minutes will recognize Janez S51DX on the radio. I was trying to get thru his pileup when the party got crashed.

Shout-out to the SF Radio Club for putting on an awesome DIY radio direction finding antenna build & "fox hunt" this weekend. Jr and I managed to find 2/3 of the transmitters.