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KB7ZUT

@graybeardradio.bsky.social

Radio, radio, radio, radio with a pinch of (you guessed it) more radio.

127 Followers  |  57 Following  |  39 Posts  |  Joined: 28.11.2024  |  1.8525

Latest posts by graybeardradio.bsky.social on Bluesky

Hey Colin did you figure this one out? Let me know and I help with the modeling if needed.

28.04.2025 14:55 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Hi Colin, what are you using to weather proof your coax ends inside the balun enclosure?

09.03.2025 12:37 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Formula

Formula

Here is the basic formula for a loop inductance in free space (air is close enough)

10.02.2025 14:29 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

For that dimension, you should see ~2.64uH per loop, so 5.28uH total. Maybe a little higher depending on the mutual inductance. You can also measure it with your NanoVNA too. it would be fun to see if the LCR45 and the NanoVNA agree.

10.02.2025 14:19 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Colin, using the hula hoops for support is a brilliant idea. I want to try is on a multi loop.

09.02.2025 14:02 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Seeing double this morningโ€ฆ #Hamradio

02.02.2025 14:23 โ€” ๐Ÿ‘ 8    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Hey Colin, I have used several Anker power banks for both radio and non-radio projects with great success. And even though they are switching supplies (all power banks are) they have not been a nightmare noise generators. I would guess the Charmast PD is not fully functional.

02.02.2025 14:19 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Thanks. I kinda think of it as an electronics and an art project at the same time. Plus itโ€™s easier to troubleshoot if you can cleanly see everything in the layout.

01.02.2025 05:01 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Completed a 40M Direct Conversion Receiver for the Soldersmoke Blog challenge. Really nice audio as a bonus. #hamradio

31.01.2025 17:23 โ€” ๐Ÿ‘ 23    ๐Ÿ” 3    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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The story of 1206 SMD parts. My new favorite book from Amazon. Lots of great adventures will start in those pagesโ€ฆ

17.01.2025 21:56 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Franklin Oscillator oscillating. Nice and stable and holding 7.003MHz for a hour. Still needs shielding to prevent stray capacitance (ie my hands) from de-tuning it. #hamradio

15.01.2025 22:33 โ€” ๐Ÿ‘ 7    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
Preview
Mint Tin Solder pads (Manhattan style on a single sheet) These are a nice little PCB that fits into the standard mint tin many of use use for our little QRP projects. They are based on the Manhatten solder pads. the PCB is double sided and one side has larg...

Hi Dave, I got them from Kanga Products in the UK. I also like their Manhatten pads too. www.kanga-products.co.uk/ourshop/prod...

14.01.2025 14:56 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Working on a new home for the Franklin oscillator. #hamradio

13.01.2025 16:08 โ€” ๐Ÿ‘ 9    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Living life in Smith chart โ€œForbidden Area.โ€ #hamradio

09.01.2025 15:48 โ€” ๐Ÿ‘ 5    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Finishing up a 20dB RF amp for the 40m direct conversion receiver. Manhattan never looked so good. #hamradio #buildRFyourself

08.01.2025 14:41 โ€” ๐Ÿ‘ 15    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Homebrewed Elliptic band-pass filter for 40m. S21(blue trace) S11(yellow trace). Now on to the rest of the direct conversion receiver. #hamradio

03.01.2025 03:06 โ€” ๐Ÿ‘ 6    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Local MW Broadcast Station KIVA AM successfully distroying my 40m Homebrew direct conversion receiver's frontend with their monster signal into my vertical antenna. Time for new filter to eliminate them... #hamradio #deathToAM

02.01.2025 16:27 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Happy New Yearโ€™s Eve everyone. May the fireworks be outside and not from the back of your radio.

31.12.2024 14:46 โ€” ๐Ÿ‘ 8    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
#151: How to wind a toroid inductor | A quick tutorial
YouTube video by w2aew #151: How to wind a toroid inductor | A quick tutorial

hi Bill, I'm a big fan of the tutorial W2AEW did on his YouTube channel. His "chopstick" holder was the inspiration for my 3D printed holder in my post. youtu.be/sDIWNHOoNh8?...

30.12.2024 14:43 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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My wife just complimented me on my miniature wreaths, but was wondering why I was making them after Christmas. #hamradio

30.12.2024 03:00 โ€” ๐Ÿ‘ 52    ๐Ÿ” 7    ๐Ÿ’ฌ 4    ๐Ÿ“Œ 0

The Radio Amateurs of Canada (RAC) Winter contest starts at 0000z Dec 28th, Friday evening in the US. Modes are CW and phone, exchange for non-Canadian stations is RS(T) and QSO serial number. Canadian stations send RS(T) and province/territory. Everyone can work everyone.

73 John K3TN

26.12.2024 20:58 โ€” ๐Ÿ‘ 10    ๐Ÿ” 3    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Oops...

26.12.2024 15:15 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

that was a short break...๐Ÿ˜

26.12.2024 14:57 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Preview
allplot โ€“ A Tool for Comparing Real-world HF Antenna Performance When it comes to understanding the performance of HF antenna systems, there are only a few tools. You can measure the impedance match with an antenna analyzer, you can model the antenna to see whatโ€ฆ

Very interesting, Roland. FYI โ€” you might want to check out AF7NXโ€™s โ€œAllPlotโ€ article on antenna performance data analysis squashpractice.com/2023/01/07/a...

26.12.2024 13:44 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Time for more radiosโ€ฆ interesting that it has a PTT input. Does that just kill the RX during TX?

26.12.2024 13:14 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Wishing everyone a wonderful Christmas holiday. I hope you find a New radio or RF toy under the tree!

24.12.2024 21:24 โ€” ๐Ÿ‘ 6    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Thanks. I will definitely do search on that siteโ€ฆ

16.12.2024 03:21 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Working on a bandpass filter design that will pass most of HF (2MHz -30MHz). Lots of value tweaking, but it's time to solder something up and see how it works. #HamRadio #AmateurRadio.

15.12.2024 21:38 โ€” ๐Ÿ‘ 4    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Kinda looks like the start of a Quadโ€ฆ ๐Ÿ˜ โ€” Nice work, Colin.

14.12.2024 08:00 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

FYI Colin, You can find the trigger cables all over Alli Express for very little money. www.aliexpress.com/item/1005005...
Just be aware that not all power banks support all output voltages. And 12v is considered โ€œoptionalโ€ in the PD 2.0 standard. The one youโ€™re using looks like it would.

09.12.2024 08:47 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

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