Tips and Jottings

Radio Record, Volume II, Issue 30, 8 February 1929, Page 27

Tips and Jottings

Soldering Lugs. WHEN soldering to lugs on fixed condensers, transformers, and the

like, 2 wet or damp rag should be placed over all but the part to he soldered, as the: heat of the ‘iron:will, in the first case, melt the wax that insulates’ the shéets, whilst, in the latter case, the soldered connections inside the transformer.may be loosened. A Telephone Hint.

To get the very best results from D.X. work or erystal reception of the local station, really sensitive’: telephones are essential. Cheap. *phones are not as sensitive as more expensive ones, but they can often be: greatly improved with a little judicious doctoring. When a diaphram is vibrat-~ ing, the point in the centre is’ undergoing a great strain and energy is used up instead of making sound waves. If this strain can be relieved a little the results will be better. "A. small round hole 1-i6in. diameter drilled through the centre of the’ diaphragm will give a marked improve. ment in ‘signal strength, .: