Broadcast - 9 Oct 2022
We will begin this week with an update on Wednesday Club Technical Night session. Soon after arrival Stuart VK7FEAT had Luke Sky Warmer, the clubs trusty wood heater, ablaze and putting out heat in record time this week. This time I checked and no Stuart didn’t sneak a whole box of fire lighters into the club rooms, it appears he is just very good at getting a fire started. Thanks Stuart.
Show and tell got off to a good start with… you guessed it, Ross VK7ALH, who brought in an Icom IC-745 that originated from the mid-80s. This time not from his collection but one that is passing over his work bench for some TLR, "Tender Loving Repair".
The original release of this 100W HF base station was SSB, CW and FM, with the optional add on FM module. But AM receive only! This was a slightly later version and had the ability to also transmit in AM mode. We were informed that this rig didn't have the ability to transmit at all. At this point the pictures came out for a mental mind jog and it became apparent that this was the second visit to the club rooms by this rig. Previously we saw it after it had suffered a fairly substantial failure, if the amount of blackening and charring on the printed circuit boards was anything to go by. The Mosfet PA driver had fried, probably over an extended period of time gauging by the amount of board damage from the charring. The offending device has since been replace and as a safety measure Ross has included Gate limiting and a snubber circuit to keep it from saturating when operating in the future. All he has to contend with now is why there are some purposely cut wires in the cable loom and a few dodgy capacitors. If the rest of the repairs are as successful it will soon be better than new. I have a feeling the logic or reason behind the cut wires may take some time to decipher! Good luck Ross.
Ian VK7IG brought in his new MRD RF_PA broadband amplifier module.
This cute little module comes pre-mounted on a heatsink and over all dimensions are about 50 by 32 by 12 mm in size. It covers 2 to 700 MHz with a stated output power of 3 Watts. The module runs off 12 to 15 Volt DC and has on board mounted SMA connectors for easy patching. This makes a very versatile and potentially useful module.
Ian also has a new WSPR transmitter made by ZachTek of Sweden. The unit was running at his home QTH and the WSPR logs were being interrogated by Ian and Andre’ VK7ZAB. Hopefully the unit will make its way into the clubrooms next Technical Night for a closer examination. Looks like Ian has joined the network of WSPR contributors with it being picked up as far afield as Washington.
Lionel, VK7ZLB brought in another trusty Grundig portable radio from his collection. This time a Satellit 700 receiver, it is a smaller unit and much, much lighter unit than the Professional Satellit 650, down from 8Kg to 2Kg for the Satellit 700, but bear in mind this model did not include the word “Professional” preceding the model number. The previous unit at about 500mm wide is suspiciously close to rack mounting width. The 700 came out the following decade in the 1990s and all visual information is now displayed on a LCD screen, no moving coil meter or mechanical linear display on this one. Recovered audio quality is once again excellent and certainly puts a lot of modern equipment to shame. Interestingly it was manufactured in Portugal, not normally a place I associate with communications manufacturing, but it is certainly build to the high standard of engineering one expects from a German product. Thank you Lionel for another glimpse into the world of Grundig.
It’s that time of the year again, Andre’ VK7ZAB had the Foxes out in readiness for the upcoming Jota / Joti Scout weekend and the mandatory Fox Hunting. Fresh batteries and a once over to make sure they were still transmitting their correct idents. Not long to go now.
Technical discussions ensued for the rest of the night until we finally departed. The discussions continued on at the Friday Coffee morning session as though they were never interrupted. This time with Trevor VK7TB, showing us his latest printed circuit board designs from his previously designed circuits. Evidently with the board ordering process now being entirely completed on line. From the uploading of the Gerber files with their suitability validation and quote being done in real time and presented to you. Just tick the boxes for all the board options required, like solder mask etc and click the accept button. Boards being completed and dispatched within 48 hours. The postal side is probably going to be the major delay. It sure beats the days of Dalo Pen or Bishops Graphics to start the board process, or though using Bishops Graphic tape for a board design was very therapeutic! The rest of the morning was taken up re-organising the hall for the scouts and of course eating, intermingled with copious amounts of tea and coffee. Good to see so many club members out and about, thanks to all for the door donations towards the Tassie Ham Expo.
For those of you that were wondering about the apparent technical problem with the 2meter Repeater, VK7RAA on Tuesday morning and afternoon, well it seems to have come about from what Agent 86, Maxwell Smart would have said was, “The old stuck on microphone trick”, HiHi. The problem eventually disappeared. The good thing is the Mt Arthur site appeared to still have ample battery charge as no problems were noticed when Peter VK7PD put the Sunday re-broadcast to air, later that night. Thanks to Tony VK7YBG and helpers that looked into the problem.
Tassie Ham Expo in November - The club has decided to combine the Coffee Morning and Technical Night donations for the month of October. Our aim is to purchase some new items that can be donated to the Tassie Ham Conference / Expo in November, they will be added to the pool of raffle prizes. So next Coffee Morning or Tech Night feel free to bring along any old change or bank notes that you no longer have a use for and pass them on to a good amateur cause.
JOTA/JOTI for 2022 volunteers to assist are needed!
The Venue is the NTARC Club rooms, which is the Rocherlea Scout Hall, Archer St, Rocherlea.
The sessions will be on Saturday the 15th of October from noon to 6pm and Sunday the 16th of October from 10am till 3pm. Groups are planned to arrive in two hour blocks, split up and rotate through four activities.
At the Club Rooms we will need volunteers to assistance with:
The operation of each of the transceivers set up for voice chat by the participants.
Assembly of Morse code trainer kits, (no soldering required only a screw driver).
Sending and receiving each other’s names by Morse code on the practice keys. (No, not live to air)
Plus external to the Club Rooms:
We need local contacts to chat with the kids in case we can’t link up to other Scout venues. If you are able to assist for any length of time over the two days please let Peter, VK7KPC or the club Secretary know of your availability by e-mailing secretary@ntarc.net
UPCOMING EVENTS
Club General Meeting – Wednesday 12th October. Held at the NTARC Club Room, Rocherlea Scout Hall, Archer Street, Rocherlea. Meeting commences at 7:30pm. For those not going to the meeting there is the:
TestNet and TechNet – Wednesday 12th October. 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.
Club Technical night - Wednesday 19th October. Held at the NTARC Club rooms, 7.30pm until late.
SSTV Net - Held every Thursday night on the 70cm repeater, VK7RJG and linked to the South via repeater VK7RAF. Conducted from about 7.30pm. These SSTV images will be available on the NTARC website under ‘Blogs’.
Coffee Morning – held every Friday in the NTARC Club rooms. Get warm while you catch up, time is from 10am to noon and we look forward to seeing you and join us for a cuppa and chat.
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.
Remember equipment photos and propagation maps are available on the NTARC web site under “Blogs” for this week’s broadcast.
That’s all folks,
73 from Stefan, VK7ZSB, Secretary NTARC.
