New Collection of Dave’s Videos on Thumbdrives!

I have close to 1000 Ask Dave videos, and some of them have been popular. I’ve put together a thumb drive with ten videos—my most frequently viewed—available for only $29.95, postpaid anywhere in the US. You can see the details at Best of Daves Videos. They’ll make great club programs or for other get-togethers.

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YouTube Channel Hijacked–Now Fixed!

Thanks so much to the folks at YouTube and Google who helped me recover. Also a special thanks to Steve Goodgame, K5ATA, at the ARRL, who got me pointed in the right direction.

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IC-7300 Firmware Update Charts

Here are the charts from Ask Dave 378 about updating the firmware on the Icom IC-7300. The charts can be found (PDF) by clicking here.

Here’s the video:

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Derivation of the 468 over f formula for the length of a dipole

Per request from KEØKRO, here is the chart showing the derivation of the formula that the length in feet of a dipole is 468 divided by the frequency in Megahertz.

Also, you can go here for a higher resolution PDF for printing the entire presentation.

This appears in the video “Frequency, Wavelength, and the Speed of Light (Ask Dave 358)”.

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KE0OG Health Update

Still recovering from bad episode of gastroinstestinal bleeding. Very anemic at the moment, on oxygen, at home, but trying to walk more than 10 feet leaves me exhausted and completely out of breath. Had 3 units of blood last week. Will try every week to do livestream on Thursday evening, US time, 7pm Mountain standard time. 73, Dave, KEØOG

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My QST Article, “Exploring Radio Mathematics”

My article on exploring radio mathematics was just published in the November issue of QST. Unfortunately errors crept in, which has generated lots of emails. I put together a page on my website that collects and collates the errors. Check it out here.

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Unusual J-pole Antenna (Ask Dave 302)

Here’s the drawing that goes with Ask Dave 302. Click here to get the pdf.

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Website for info about DSTAR

Brad Rich provides this link for those wishing to learn more about DSTAR. Note it not only has lots of good info, but lists other links as well. Here is the link; you can just click on it to go there:

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Oggie Harry Rundall, AC3EK, Discusses Elbow Connectors

Male end of elbow connector, photo by AC3EK, used by permission

Harry reports: “I had asked about erratic power behavior on the ICOM 7300 on the mode FT8 last Saturdays Q&A. Well it turns out it was the elbow connector I had in line on the back of the rig to my jumper going to my MFJ-697 dummy load/SWR meter. Being a Field Engineer, back the day, with Hewlett Packard Medical (1969-1979), I applied the good ole troubleshooting methods. Lightly tapping on the back right hand corner of the cover to the rig, when it was in the tune function of FT8, I could eliminate the problem, i.e. recover proper power output. Next I grabbed the body of the elbow connector and ever so slightly rocked it and sure enough the problem appeared/disappeared. Next, removed the connector and placed the jumper RG8X directly into the rig. Problem went away. I tapped the top- while in tune mode, and no repeat of the problem. Talking to a fellow ham buddy about this He heard that these elbow connectors can be a problem. Notice in the attached photo (Taken with a Nikon 7000, Sigma lens set for micro photo 1/1000 at F13) of the pin of the male part of the connector in the blown up photo notice the scarring to the pin. Thought I would share this for your library of troubleshooting connectors issue. All is good now!! 73s Harry AC3EK”

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MFJ-17754 Instruction Addendum from Ask Dave 265 and 266

In Ask Dave 265 and Ask Dave 266, I mentioned an Addendum to the MFJ instructions. This addendum describes that the antenna comes pretuned too long and will need to be shortened, and gives instructions for doing so. See the addendum by clicking here.

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