g21 Components and hardware

see more surplus components on page f21 and pg-f22

Mounting components for radiotechnical equipment

The picture shows a 4-pack to the left, two sets of 77mH coils to upper right, and a 88mH toroid at lower right side

77mH pupin coils in Europe (for telephone lines and RTTY...)
instead of the 88mH toroids, which probably are rather old - even in America, we use 77 or 80mH for different cables,
here is shown the 77mH set of coils for ground cables, it is 4 pot-cores in the package.
Since the 88mH value is not optimum, only somewhere near optimum priced, it is no reason for not using the even more
optimum 77mH coils - particularly when they are free. Unfortunately the 80mH coils are packed with resin fill, so the coils
are somewhat impossible to remove from the package.
See page-c11 for application of a 77 or 88mH coil as oscillator

A useful book for finding VHF/UHF circuit diagrams and components (SSB Electronics 1984)

A useful tool from 1932 (was used to adjust filament voltage on the local broadcast transmitter), it is 2x 0.8 ohm
rheostats with 0.1 ohm 5W series resistor to measure the current, but the smaller resistor has lighted up on many occasions

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updated: 2004.11.14