Mar 8, 2015

VHF Moon bounce Concept!!!

To communicate over the longest distances hams use moon bounce. VHF signals normally escape the Earth's atmosphere, so using the moon as a target is quite practical. Due to the distance involved and the very high path loss getting a readable signal bounced off the moon involves high power ~ 1000 watts and steerable high gain antennas. Receiving these very weak return signals, again involves the use of high gain antennas (usually the same ones used to transmit the signal) and a very low-noise front end RF amplifier and a frequency stable receiver. However, new and recent technological advances in weak signal detection has allowed the successful reception of signals off the moon using much smaller or less well equipped stations allowing reception of signals that are "in the noise" and not audible to the human ear. One of these modes is JT65 which is a digital mode. Due to the delay of the signal traveling to the moon and back (travel time approx. 2.5 seconds), a person transmitting may hear the end of his own transmission returning. 

Some pics of recent full moon at Chennai on 6th March Friday.

Mar 3, 2015

OM VU2VIT Vittal Ji became silent Key : Condolences & Remembrances from all HAM's

Its a sad news for all HAM / Amateur radio lovers as a very senior HAM and legend in his own terms today became silent at his QTH in Chennai, he was 83 years old . All Chennai Hams express their sincere condolences & remembrances to this great person and pray for his soul to rest in peace. 

His profile from


I am 83 years old and have four children. K.Srinivasan VU2KSV, K.Kamakshi, VU2KEL, Swami, W6SMI, K.Bala, VU2KAF. Two boys and 2 girls a balanced lineage! 

By profession I was an accountant and retired from a Tata Group of companies as Regional Accountant in 1991. I was an active amateur photographer and organised international salon in the year 1956. I was hardly 23 years old at that time. 

Subsequently got interested in radio homebrewing from 1960. At that time it was great mystery and wanted to know how radio works. This later led me to Hobby of Ham radio.
Even as an Ameteur Radio man my propensity for organisational work dominated and was Jt.Secretary and Treasurer for 5 years and President for 2 years of MADRAS AMATEUR RADIO SOCIETY continuously till 1989. During my tenure VU2RKR VU2TTL VU2DQP were secretaries who ably carried on the activity of promoting ham activity by conducting regular classes and arranging field days. Subsequent to my retirement I took up reviving the ARSI which was suffering dimnished membership and was active in running the qsl buro for nearly 10 years. This work really increased my popularity.

I also made hundreds of straight keys and sold them in spite of the warning of notable CW enthusiast VU2DX OM Sifuddin. Hi. Along with VU2UR, VU2RMJ, VU2NDR spearheaded activating Pamban Island, AS-173 with 7 other hams. VU2FBI secretary of Ramanathapuram club and District collector provided space in their Premises and geuest house for the purpose. Since 1993 annual eye ball meet is organised continuously at Mahabalipuram till now and will be continued on every 2nd Saturday of each February. I get able assistance from VU2INA, VU2KBX, VU2MPK and the support base is increasing. Salient feature of the meet is that no money is collected for participation. There is no free lunch and each take care of himself. No speeches or lectures and no formal agenda. Hams can show off there homebrew articles. Senior hams are honoured on the occassion.

This hobby gave me pleasure in home brewing and knowing prominent hams vu2nr and vu2rm. Wish you all enjoy your hobby and share your knowledge.

73s vittal