Mar 11, 2023
Eyeball at Marina Beach on 25th Feb 2023
The Madras VHF Group had casual eyeball at the iconic Marina beach on 25th Feb and several HAM's participated. It was an interesting session with a demo of DMR radio also. Chennai HAM group recently added a feather to their cap by installing a UHF DMR repeater
Feb 12, 2023
Dec 7, 2022
Why HAM's need to explore the Digital Space - A perspective VU2OW OM Rajesh
Why should we go digital, example DMR?
Answer: As hams we should adopt to technology changes and new features. DMR provides connectivity to worldwide hams through a complex network of computers and internet. It is as if whole world the comes "compressed" in digital form into your handie talkie.
Facts :
DMR technology, that is, the algorithm used to digitize voice is not available to users as open source. Hence, there is a price to pay for the encoder and decoder chip, which does the job. Hence the equipment we use for this is expensive and there is very less homebrewing in this area.
Unlike DMR, DSTAR, C4FM and others, there is a freeware or opensource technology called FREEDV. There are no expensive royalties to be paid. We can use our computer with software we can write ourselves and convert any radio to operate in FreeDv, without buying expensive equipment with decoding-encoding chip in them. I have tried it and it works well. Note - there is no established network in freedv though.
As hams we should try and use the above technologies. Sometimes, digital voice has more range and clarity due its compressed nature and low bandwidth. For example, in HF, the voice clarity is improved. Unlike analog voice which sounds feeble and burried in noise, digital voice is clear - when it weakens, it stutters and dies suddenly... analog voice gradually goes down with weakening signal - that is the difference. Digital transmission has slightly higher range than analog. This improvement in technology comes with a caveat as I mentioned above. Dependency on a providers/Chip manufacturers/patents, expense and so on.
It is not a recommendation that we should drop our barebones analog equipment and technologies for the digital one. True ham is one who understands, builds and improves their analog receive/transmitting system and constantly improve its quality in all modes. Real fun of homebrewing is to build a radio from scratch and use it. THIS IS WHERE THE REAL FUN OF HAM RADIO IS - to be able to work the world without internet, service providers, companies, patents and all other dependencies - our radio - our antenna - the world, with nothing in between. We'll continue to do it while trying the new technology.
We have couple of analog repeaters in our city and it is time, we install and use our 2 brand new UHF and VHF repeaters in digital world. DMR is a well established network - Basic concept is that each radio is identified by its owner with a specific DMR ID (carrier drivers will be identified easily 😆), which can join talk groups with many types of permissions. We shall explain and introduce you all to many, many features (including SMS, texting and integration of your rig with online call sign database like qrz.com) in due course.
Stay tuned in this frequency. 73 for now.
Feb 28, 2021
Chennai HAM VU3MOA Mohan visits ARSI Hill Top Contest team @ Vetal Hills , Pune
Veteran Chennai HAM VU3MOA has an opportunity to visit the ARSI Hill Topping contest team at Vetal Tekdi in Pune on 28th Feb 2021.
Vetal Hill (Marathi: वेताळ टेकडी ) is a prominent hill in the city limits of Pune, India. The hill is the highest point within the city limits, with an elevation of 2600 ft. There is a temple of Vetala located on the top of the hill from which the hill derives its name. The Indian Forest Department maintains an observation deck near the temple. The hill is also known by its Marathi name, Vetal Tekdi.
The HAM team @ Vetal Tekdi was headed by amateur radio operator OM Rabde Vilas.
Feb 23, 2021
Dec 26, 2020
MARS (Madras Amateur Radio Society) conducts its first ever virtual AGM successfully
Today 27th Dec 2020 MARS (Madras Amateur Radio Society) successfully conducted its first ever virtual AGM and passed the annuals accounts and all resolutions on taking MARS forward. Thanks to the President , other office bearers and all the committee members for taking time out from your day to day schedule and helping run this society.
Nov 25, 2020
Chennai HAM Team support for Disaster / Emergency Situation communications related to Cyclone Nivar November 2020
Chennai HAMS team of disaster communication veteran OM VU2DH Das and a highly accomplished technical HAM VU2ABS Arvind are at Cuddalore District Collectorate to help local administration with HAM Radio communications support for Cyclone Nivar
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