Broadcast - 18 Dec 2022
We will start this week with a round up on the end of year dinner - Well for summer it was certainly a cooler night than was expected and unfortunately there were quite a few unable to attend due to sickness and the inevitable clashing of engagements at this end of the year. However a good number of members rocked up to the Mowbray Hotel in Launceston on Tuesday evening for the annual NTARC Christmas Dinner. It was great to see at least half a dozen faces we haven’t seen for quite a while, mainly due to distance or health problems. With the re-unions came much laughter and cheerful banter going on as we all discussed the menu before ordering. There was an excellent selection, something for everyone. Orders were taken and service was fast. The food was magnificent, everyone seemed happy. There were no disappointments this year as there were adequate supplies of Sticky Date Puddings and Banana Splits to round off the evening. A great time was had by all. We all made our way home thoroughly satisfied.
The last Club Room Technical Night session for 2022 also saw a great roll up of attendees.
I mentioned before that it is summer, but thank you Stuart VK7FEAT, for stoking the fire up and removing the chill that we must all have been imagining.
Ross, VK7ALH came in with a couple more examples of what has been across his repair bench recently. Not radios this time but never the less very interesting.
The first was a UniMig CUT40 Inverter Air Plasma Cutter, basically the complete unit utilising the same mother board as shown and discussed at the last Tech Night, mainly because it incorporated a “Spark Gap”. The second item was a Lincoln Powercraft 185, a small single phase inverter welder that is capable of 185 Amps and weighs in at just 4.2 kilograms and is physically very small.
We received a very interesting run down on construction, operational differences and general design. But as both these units have been deemed as “Commercially uneconomical to be repaired” and were replaced under warranty they were receiving special attention as to salvageable electronic components. Everything from high capacity and voltage capacitors, switching transistors, HF usable Ferrite cores and physical cases. It would be such a shame to send them to recycle.
Lionel VK7ZLB, brought along a quite different co-axial cable assembly for a fixed frequency transmitter installation. It provided “stub” blocking filters for the 3rd, 5th and 7th harmonics. Rather than the usual off the shelf “T” connectors Lionel used machined sections of copper to tee of the stubs from the main passing through RG213 co-axial cable.
All stub calculations were based on a specific fundamental frequency in the 104MHz area.
To compliment the filter he had the accompanying 50 ohm four port power splitter that he also made. This provided equal power feeds on all ports, allowing for the connection of four mixed polarisation antennas. This splitter was constructed from solid brass stock about three quarters of a metre long and would have required some pretty accurate end boring to hollow it out. The incoming feed was an “N” type connector with four BNC sockets at the other end for output. Once again a high standard of construction.
Lionel also brought an assortment of 50 Ohm home constructed low power dummy loads. He instructed us in ways of maximising the usable frequency response from appropriate construction techniques. They consisted of PL259, “N”type and BNC plugs and could offer far superior bandwidth performance compared to a lot of E-bay very suspect “cost effective” alternatives.
As would be expected all discussions were interspersed with copious amounts of coffee, tea and eating. Many thanks to members that furnished the night with sandwiches, cakes and even doughnuts to make things more festive. An excellent end to a technical year. Thank you to all who have contributed to the very eclectic selection of items that have passed through the club rooms for show and tell throughout the year, they certainly have acted as a catalyst for many discussions.
From everyone at our technical sessions both club rooms and on air throughout 2022, we wish all a very happy and safe Christmas and we are looking forward to more Amateur Radio fun in 2023.
Don’t forget there is still one more TestNet and TechNet session with Nic VK7WW, at the helm next Wednesday night.
While talking of Nic and his CW course it is nice to note that Peter VK7KPC, has received a certificate in recognition of his participation in the Don Edwards Memorial Slow Morse Contest for 2022. This contest is run by St. George Amateur Radio Society Inc. in New South Wales and is generally held in May each year, well done for your participation.
Remember all equipment photos are available on the NTARC web site under “Blogs” for this broadcast date.
Friday coffee morning, saw Ros as usual arriving early to set the room up and possibly vacuuming the floor, as we have been known to forget vacuuming before leaving on a Wednesday technical night, sorry Ros. We really do appreciate your dedication for what realistically ends up being nearly every Friday in the year! When you consider you also bake a cake for each coffee morning that’s an awful lot of work. Thank you Ros. We had a very large roll up for our final coffee morning, with much merriment, chatter, coffee and the obligatory food consumption. A happy ending to the year.
It looks like Santa must have come a week early to some of us that are in his “Good Book”. Bill VK7MX, showed off his brand new small, as in hand held, spectrum analyser. This is the latest incarnation of the 2.8 inch screen version and now sports a very crisp 4 inch colour display screen. This is a considerably useable size increase over the older model and much easier on our aging eyes.
The unit is capable of functioning well over 5GHz, both in spectrum analyser and signal generator modes. One wonders if it will be wrapped up and left under the tree until Christmas day?
With that now behind us, this is a gentle reminder that the clubrooms are now closed for the Christmas/New Year recess but will re-open on Friday the 13th of January 2023.
It’s that time of the year again - All club members should have received an e-mail with instructions on renewing their membership for 2023 by now. If you haven’t received the e-mail please e-mail the secretary with your updated contact details. For those that we don’t have an e-mail address for, you should have received a letter and renewal form send via snail mail by now.
P.S. A big shout out to Martin VK7JAH, hope you are soon out of hospital and on the mend.
UPCOMING EVENTS
The last TestNet and TechNet for this year will be - Wednesday 21st December. TestNet/CW course on 3.580MHz from 7pm till 7.30pm….and a TechNet on 3.567MHz from 7.30pm till about 8.30pm. Your host for the evening will be Nic VK7WW. This is the last “formal” night, but who knows it might be worth a frequency check over the Christmas New Year break as amateurs have been known to just talk for the fun of it.
The last Friday Coffee Morning for this year has just passed us by. Will be resuming on Friday the 13th of January at the NTARC Club rooms.
The last Club Technical night for this year has also passed us by. It will be resuming on Wednesday the 18th of January at the NTARC Club rooms and yes it will be 2023 by then!
FINALLY - A reminder to all members that if you have any items of news you would like added to our weekly roundup, no matter how trivial, then please email them to the Secretary at the following address news@ntarc.net all items to be received no later than 5pm on the Friday prior to the Broadcast.
That’s all folks,
73 from Stefan, VK7ZSB, Secretary NTARC.
