Monday, August 28, 2017

more 70 MHz (4metre band) info

just some more followup on the WIA band plan submission for a tiny slice of  70-87 MHz segment,  WIA asking for 70.000 to 70.500 MHz,  that 500kHz to play with,  definitely more than adequate in my mind, plenty to experiment with.

Noting what Region1 has for a bandplan, if we could get the same slice here (Region3), then obviously we need to use the same Bandplan as Region1 to be able to work Region1 from Region3 during E's.

70.200 MHz  SSB calling.

70.450 MHz  FM calling ,  using 12.5kHz FM channel spacing.

70. 260 MHz       -  AM calling !!   really ??  that's legacy modes for sure.

70.100 to 70.250     that's 150 kHz for weak signal nodes,   heaps of space.

70.300 to 70.500  FM at 12.5 kHz spacing = 16 channels,    that's plenty of channels !!

I think  70 MHz would be good fun, with ducting, tropo and E's propagation modes.

fingers crossed we get a slice to play with.

Tuesday, August 22, 2017

Modifications for the TYT TH-9800 FM quad-bander mobile transceiver

These TH-9800  quad band FM transceivers  (a clone of the Yaesu FT-8900 transceiver) have an issue of blowing the transmit driver FET.  I have documented a modification to fix this, as it would be a considerable amount of work to replace the drive FET, or even the PA FET for that matter. Easier to do the mod and run at less output power, better than having a dead tx PA. It basically adding a 8v (7808) regulator into the supply circuit for the Driver FET,  which is fed hot from the 13.8v DC input.

Reducing RFI from your vehicle for operating mobile

I have documented the modifications to my 4WD  vehicle that I use for mobile and portable operation. It was only that in past year I have decided to operate HF, whereas in the past I only ever had VHF and UHF equipment, so RFI radiating out and also from within the vehicle was not so much of a problem, but is more so for HF.  My web page includes photos.

VK5KK microwave photos from WIA AGM Hahndorf 2017

these are the photos I took of David VK5KK's microwave equipment display,  held on the Open Day, as part of the WIA AGM weekend, 21st May, 2017,  located at the Hahndorf Oval.

David was operating  all bands from 1.2GHz through to 122GHz ,including the 10GHz EME station.

Thursday, August 10, 2017

Photos from WIA AGM in Hahndorf for VK5ZD's microwave equipment

I have now collected and edited up the photos I took from the WIA AGM held in Hahndorf on 20th May 2017 and from the Open Day held on 21st May 2017,  this particular web page contains the photos of Iain VK5ZD's microwave equipment, I documented this to show what different people doing in terms of microwave band activity and experimentation. All bands 1.2GHz through to 122GHz.
I also preparing the same for David VK5KK's microwave equipment.

Friday, July 28, 2017

MAD 23 on 23 (Microwave Activity Day) 23rd July 2017

I went portable for this months MAD 23 on 23, since it coincided with 23rd falling on a weekend, this month a Sunday, the VK4's organised to start at 12 noon, I went to the old Army Artillery Base up on North Head, Sydney, QF56pe, I chose this again, as it has some flat, clear area, reasonanly void of trees, and having a clear takeoff up the coast and to the north (direction of brisbane). The aim was to try and hear some of the activity from vk4  on microwave bands via AE. I took 23cm, 9cm and 3cm equipment. Tee'd up some attempts with some of the VK4's and VK2MAX on 1296.150, (via  we waited for some Brisbane bound jets from Sydney to be in position half way between us, we gave out calls to each other, but unfortunately nothing heard.  Found out later there were a handful of 23cm stations setup  out Penrith area.   Next MAD 23 on 23 that falls on a weekend is 23rd September 2017. Maybe next time to go Blue Mountains again.

the gridpack is for 23cm,  the square panel is one of the Geelong ARC 3.4 GHZ converted panels, the 60cm dish is ex-Austar dish and  modified feed for 10GHz

Mobile phone coverage comparison

when travelling to and from GippsTech noticed there a gap where there is no mobile phone coverage, I had known that was case for Optus on previous trips, but this time took note to see how Telstra handled the same segment of road, as can bee seen comparing my APRS versus VK2JDS APRS using Telstra. They both not covering that segment of road.

Friday, July 14, 2017

GippsTech 2017 summary

Had a great time again at Gippstech, put faces to some more callsigns, good lectures and displays, learnt lots. A bit cold on the monday drive back, -6 deg out in far east Gippsland, but at least no rain and snow.
There was a bit snow on the roadside near Nimmatabel on the Friday drive down.
Did some on-air microwaving again from carpark and also from Powerworx hilltop on Sunday afternoon at conclusion of Gippstech, Ralph VK3WRE gave us some 10GHz contacts.
Tested 23cm, 9cm and 3cm gear.

Friday, June 2, 2017

GippsTech 2017 - 1st and 2nd July 2017

registrations for GippsTech are now open today, as it only 1 month away until its on again, 1st and 2nd July.
I driving down again, taking 23cm and 9cm equipment for some live contacts on the weekend. Maybe 10GHz.

Tuesday, May 2, 2017

RF site testing at QF46qu on Easter Sunday, 16th April, 2017

Doing some site testing at a friend's farm at QF46qu at Gowan, north west of Bathurst NSW.
my GPS estimated 950m ASL mostly cleared, with almost 360degress of clear horizon, good for playing radio. As it was Sunday morning I made use of the fact that the WIA morning broadcast was one reason to listen for it on various known frequencies including 2metres, 70cm and 6metres.

I could hear 146.775 Newcastle, 146.725 Somersby, 146.850 Maddens Plains, 146.975 Knights Hill,  53.650 Maddens Plains, 146.950 Mt Ginini.   Could not hear anything from Dural. This was using quad band radio (TYT TH-9800) and quad band vertical from the vehicle. Should be much easier with some yagis up a mast.

Looks to be excellent site to run microwave equipment from (23cm and upwards).

 a little bit of trees to north east,
 looking to north coast & mid north coast NSW, all clear.
 looking to Newcastle through Sydney, all clear
Looking back to Bathurst
 Looking to south and VK1
Looking to VK3 & VK5 all clear.
Looking west, a couple trees
Facing to north west, highest point where these pine trees are.
 Looking north, a few sparse trees, but nothing Roundup or a chainsaw can't fix
Good flat area, for parking, camping, whatever.