UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Leon Crampin · 3rd Aug 2017, 7:39 pm

Find a small 4 pole change over relay with the same coil voltage as the radio's battery. (If necessary, take advantage of improved battery technology and make room for the relay by fitting a smaller battery). Arrange for the relay to be energised on the less used waveband. Also consider an "economy" circuit in which the relay coil current is reduced once it pulls in - the holding current can be about 20% of the pull-in current, so it's worth doing on a battery radio.

Find some workable contacts on the existing switch (you only need one) to control your relay, if necessary, paralleling worn contacts. The set will then operate as designed without external cosmetic changes.

Leon.

3rd Aug 2017, 7:39 pm	#7
Leon Crampin Octode Join Date: Nov 2005 Location: Surrey, UK. Posts: 1,870	Re: Pye P170BQ wavechange switch Find a small 4 pole change over relay with the same coil voltage as the radio's battery. (If necessary, take advantage of improved battery technology and make room for the relay by fitting a smaller battery). Arrange for the relay to be energised on the less used waveband. Also consider an "economy" circuit in which the relay coil current is reduced once it pulls in - the holding current can be about 20% of the pull-in current, so it's worth doing on a battery radio. Find some workable contacts on the existing switch (you only need one) to control your relay, if necessary, paralleling worn contacts. The set will then operate as designed without external cosmetic changes. Leon.