Saturday, April 5, 2014

coils winding direction

In the year Y2K i made few transmitter ckts. Only resources available to me was old analogue communications receiver with no digital dial (!), AM SW RADIO and simple-calculator, logaritham tables , formula book ( i collected the formulas and made  my own book ! ) on those days there was no internet. If we forget something, then we had to consult the engineering books. I had lots of books of theory, practicals and my own konsultations papers.

In one of the scrape-book i had drawn this ckt.

coil winding 

At that time alladin former was widely available in the form of SW,MW oscillator and antenna coils.

Another type of coils were the metal cans. KANK type, metal can type was only available for the 10.7MHZ fm radio if, 5.5mhz TV FM Sound if and 455KC if coil set, but those were very hard to make/change for other frequency. as they had internal capacitor. Coil wire size was very thin say SWG45, So, we used this alladin former for all experiemnts.

When i was replicating the VU2ATN  20 meter CW Transceiver,  I had to find out the hot and cold property . It was hard for me to understand at that time. I put RF probe on both secondary ends and was puzzled to find they both were showing RF. Hot. He he he. Log time After that experience and further reading got to know that Hot and cold means the  sinusoidal phase directions the rf is taken or given.

After that i made few more 20meter, 80 meter transmitters. valve transmitters. It was easy. In those days in the smae locality we had two big big homes. I had two radio room with big antennas on both houses ! So, whenever i did tx experiments i did not ask other hams to listen to it. I tuned up and do the listening test myself. gone were the days. I regret that on those hay-days i could have bought my own 50k transceiver. Anyway this is life.

On the marry note:- I should have married some  bhavangar girl, so on social visitation to her home, i might have found some communications receiver, tranmitter from ship-breaking yards. Fact is that beautiful womans uncle had one yard in alang. Year was 1992-94. Both were precious. Woman and com equip.