VK Logger Ham Radio Forum Archive

If you could make the doppler radar unit small enough it would work better if it was carried by the skydiver. The ground is a much bigger target.

If it's a 1/4 wave vertical then you shouldn't need a loading coil. A loading coil is only required when the antenna is less than a 1/4 wavelength. The size of the coil depends on (a) the actual antenna length and (b) where you want to put the coil. There are some on-line calculators that will work ...

Amazon won't ship it to Australia.

That will be one hell of a drive. QF53TC is in the Pacific Ocean!

Sounds OK to me, although I wouldn't bother adjusting the tuner a second time.
1.5:1 VSWR is only a 4% power loss (<0.2dB); just accept it.

From Mike, K6ML... New world record: 139 km on 122 GHz 17 Feb 2020: QSOs between Mike, K6ML, on Mt Vaca (CM88WJ75ON, 835m ASL) and Oliver, KB6BA, (at 1225) & Jim, N9JIM, (at 1250), both on Mt Umunhum (CM97BD18VJ, 1016m ASL) WX: Dew Point -11C, Air Temp +15C, path loss ~ 225 dB, atmospheric loss ...

Maybe this stuff?
http://resources.permarproducts.com/Pol ... ochure.pdf

Something local that's similar:
https://pricewiseinsulation.com.au/prod ... nsulation/

Some time ago I created a website that calculates the atmospheric losses due to oxygen and water using data from the various Bureau of Meteorology observation sites in Australia. You'll find the site here . These figures assume a basically horizontal path across the earth and are in addition to the ...

Here is the video of the meeting:

Hi all

I recorded the meeting and will post the video on YouTube within the next few days (needs a bit of editing).

+20dbm. That's the medium power setting on one of these (DVB link Tx/Rx):

Someone at the 7 network might not be too happy if you fire up on 2043MHz.

Hi Adam.
You misunderstand. What I mean is that I've not heard from anyone wanting to start it in VK5.

I have floated the idea of 23 on 23 with a mate in VK5 who thinks it is a marvellous idea. He will spread the idea among VK5 proponents of the 23cm band. Don't know who your mate is, but, aside from this post, I've not heard anything about this. Neither have the other six 23cm operators in our club...

OK. Just for clarification, both the photos in my previous post were taken with the antenna on it's side. In normal use, the grid bars are horizontal and the biquad feed is vertical. There is nothing to be gained by adding mesh for use at 3.4GHz. The link posted by Lou will give the required dimensi...

VK3QI wrote: ↑Tue Aug 06, 2019 3:33 pm In your picture of the bi-quad, shouldn't the parabolic reflector be turned 90 degrees to have the bars horizontal?

Or is the bi-quad orientation incorrect?

The bi-quad orientation is correct. It was just convenient to clamp the antenna on it's side in a bench vice to take the photo.

Replace the original 2.4GHz feed with one of these.
I've made 2 of them for 3.4GHz and they work well.

More testing... This time I used the five different 10MHz sources as the reference for a 'Kuhne MKU LO 8-13 PLL' oscillator which was configured to output 11,952MHz (x 2 + 144 = 24,048MHz). The five sources are as shown in my previous two posts, namely my home brew GPSDO, a BG7TBL GPSDO, a CIC OCXO,...

VK2XAX wrote: ↑Thu Jul 04, 2019 2:42 pm Ian,,, the link to your band limit file doesn't work any more - do you sill have that to share ?

Try here

Hopefully it's still compatible.

An finally, the Efratom Lpro-101 (the previous post wouldn't let me add any more images).
All I can say about this device is that I don't recommend it if you want a clean 10Mhz reference!