Broadcast - 20 July 2025
One of the most common subjects for discussion that keeps reappearing at technical nights and morning teas over the last year has been toroids, baluns, chokes, ferrite beads and interference suppression. Wouldn’t it be great to have everything answered that you were afraid to ask? So……..
Calling all amateur radio and electronic enthusiasts! Dive into the fascinating world of toroidal components with our hands-on Toroid Test & Measurement Presentation by Trevor VK7TB.
Trevor will demystify the toroid colour code system - from red (T-37-2) to yellow (T-68-6) and beyond - so you can select the right core for your frequency range and power level. Or are the painted on colours just for decoration by some manufacturers?
Whether you're building baluns, filters, or matching networks, understanding toroids is key to cleaner signals and better performance. This session will attempt to cover some of the following:
• Colour Code Identification for Popular Cores
• Ferrite or soft iron core centres
• Frequency Response and Core Saturation
• Inductance and Q Factor or Quality Factor Measurement
• Testing Tools that can be used and maybe even some DIY Winding Techniques!
If all goes well the testing oscilloscope display should be available on the large screen monitor for easier viewing. As there is only a couple of hours available for this presentation we will see what can be covered. I am sure Trevor might be tempted into a follow up session for the remainder and maybe even covering the now ubiquitous nanoVNAs and other tools like LCR meters to evaluate your toroids with accuracy. Presentation to be held at the club rooms on Wednesday the 6th August, about 7.30 pm.
So, to start things off this presentation is perfect for beginners and seasoned operators alike as it will blend theory with practical demonstrations. So bring your questions, your curiosity and your toroids!
UPCOMING EVENTS
Amateur License training - Peter VK7PD, is currently running Saturday upgrade classes, all are welcome, please contact Peter or the secretary if you are interested.
On Air Test and Technical Net session - Every Wednesday, Test-Net and CW course on 3.580 MHz from 7 pm, then a Technical Net on 3.567 MHz from 7.30 pm till 8.30 pm. Your host for the evening is Nic VK7WW.
Club Room Technical night session - The next session will be Wednesday the 23rd July, from the usual time of 6.30 pm at the Club Room Archer Street, Rocherlea.
Unlocking the Secrets of Toroids! Test & Measurement Presentation by Trevor VK7TB. Wednesday the 6th August, doors open at the usual time of 6.30 pm, presentation about 7.30 pm, at the Club Room Archer Street, Rocherlea.
Coffee Morning - Held every Friday in the NTARC Club rooms. Time is from 10 am to noon.
Finally – If you have any items of news please email them to the Secretary at the following address news@ntarc.net all items to be received no later than 5 pm on the Friday prior to the Broadcast.
That’s all folks,
73, Stefan VK7ZSB
