VK Logger Ham Radio Forum Archive

Why the 18mm error for the driven element is interesting. While an 18mm difference is more than I would have anticipated too, keep in mind that the physical Yagi built is not the same as the computer derived model ... - several small dimensional changes (2mm at the REF, 1mm at D1 a 'sensitive' elem...

... a bit of that Cascade Hop beer and you won't care about the SWR

Hi Brian, An observation from your photos ... the coax tails to the DE connection points are curved and with solder lugs, so are effectively adding say 5mm to each side of the driven element. Putting this overall 10mm of extra DE length into the antenna model the SWR curve is ... 2m7_longDE.jpg ... ...

Nothing here yesterday at all Joe. Last heard was around 08:50 UTC on 01 Jan when it "went to sleep". Earlier that evening the voltage reading indicated sunset was 05:20 UTC It was stronger on the Beverage to 130 degrees than the one to 090 degrees ... so, at a wild guess, possibly between...

Check the element spacings Brian ... seems a touch of dyslexia in your listing with the D1 spacing :? K7MEM_DL6WU_2M7.jpg Edit: to answer the other questions ... I rounded the dimensions to the nearest mm before putting them into 4NEC2 and used the uncorrected ... insulated boom ... dimensions for t...

Hi Brian, The short DL6WU Yagi's come with a warning on the output page: Warning: The specified Boom Length of 2500 Millimeters is to Small. Boom Length should be greater than 2.2 Wavelengths. To check the design is OK I put the calculated dimensions into 4NEC2. The result is quite OK except that th...

Brian, 1. The gap is taken up by the coax tails going from the RG-58 to the DE connection points. The aluminium and the coax tails all forms part of the driven element, so the tip to tip dimension is near enough. Likely the TV antenna element material is 3/8" or 10mm diameter aluminium tube, so...

VK3LU wrote:... I don't know whether I could bend tubing successfully around a 50 or even 60+ mm semicircle

Try a 'tube bender' search at places like eBay (or TradeMe in ZL).
I got one as below for a few dollars and used it for folded dipoles and LFA loop corners.
73,

Comparison of PS-56 CW signal on Beverages pointing in two different directions ... http://www.qsl.net/z/zl1rs//images/ps56_20151229_1926utc.jpg top image from a Beverage pointed at 240 degrees lower (stronger) image from Beverage pointed at 320 degrees Voltage decoded at the time (19:26 UTC) was 36...

The NOAA trajectory prediction for the position established at the balloon sun set last night is:





PS-56 'woke up' at about 18:23 UTC this morning and is strong on a Beverage pointed to 320 degrees which supports the above prediction.

73,

The PS-56 signal is now fairly even on both the 220 degree Beverage and the 275 degree Beverage here. Comparing the differential on WSPR signals from VK, this would indicate PS-56 is somewhere on the line 260 degrees azimuth from this QTH ... mid-Tasman Sea somewhere.



73,

The PS-56 'wake up' transmissions started at 17:48 UTC indicating a sun rise time of 16:45 UTC or a bit earlier. The signal is strong on the 220 degree Bev and a lot weaker on the 150 degree Bevs, so it must be greater than 200 degrees azimuth from this QTH. Wild guess for the morning based on the s...

There was a sudden voltage drop between the 10:39, 10:47 and 10:55 UTC transmissions indicating PS-56 lost the sun. Looking at the day/night terminator and considering the signal is quite strong here (and therefore probably not further than 20 degrees off the 220 degree peak heading of my Beverage),...

... big ears got the following at 08:56 UTC on the 220 degree Beverage antenna ... http://www.qsl.net/z/zl1rs//images/ps56_20151228_0856.jpg It was also readable by ear with a '539' audio report ... there is no question that it is PS-56. The last two sets of voltage telemetry were 4203 and 4211 indi...

Saw the 08:25 and 08:33 transmissions here very weakly on the 150 degree Beverages while looking for PS-57 off the coast of Brazil. After changing to the 220 degree Bev the signal has increased to 'huge'. I'll get a decode on the next transmission ...

PS-57 in "SOS" mode since 0326 UTC ... could be a weather effect again.
Fingers crossed ...

73,

PS-56 battery is now 'flat' and the controller is slipping in and out of 'sleep mode'. There was no transmission at 08:59 UTC, but the battery recovered enough without the load and PS-56 transmit again at 09:02. Maybe it will TX once or twice more, but otherwise it will be 'asleep' until 1 or 2 hour...

There was a sudden drop in battery voltage around 05:50 UTC as a result of the sudden temperature drop at the balloon's sunset. From that and the directional antennas here we deduce that PS-56 is somewhere around 37S x 165W, and the following is the NOAA prediction based on that ... http://ready.arl...

PS-56 CW is currently pounding away here on the 095 degree Beverage array, and Roger Zl1VCC reported a few minutes ago it as being "loud" in Rotorua ... so probably line-of-sight there. We are recording the battery voltage readings sent in the Morse code 'reset' string to get an idea of th...

That is QRSS FSK CW ... the signal in particular is the start of ZL2IK's callsign. The full callsign is readable in the screen shots further up the page. This morning PS-56 is still ticking away in CW every 7 or 8 minutes. Strongest signal is on the Beverage pointing to 150 degrees, but the signal s...