Emor 200; mains transformer taps. - UK Vintage Radio Repair and Restoration Discussion Forum

gkargreen · 19th Nov 2006, 9:35 pm

Hi, all, I am repairing the above radio, and wanted to know what the taps in the mains transformer were marked for, thanks!

Tim · 20th Nov 2006, 8:49 pm

From memory the british models were tapped at 240/250-220-200 and neutral. Test the winding with an ohmeter. With the mains supply disconnected, all valves and tuning lamp removed apply 24(twenty four) volts AC across the primary (Winding with the highest dc resistance) and measure the voltages between neutral and the other taps. This should give you a clue.
There will also be voltages on the secondary. If these are a factor of 10 less than normal you have a british/european transformer, if a factor of five the transformer is designed for US voltages. Similar test can be carried out with 12 volts AC, but of course if sec volts normal set is american etc.
Or, the slightly unsafer method:-Remove all valves and dial lamps and apply 6 volts ac to 6v heater winding. Then measure voltage at primary. Easy!!

Good luck.

19th Nov 2006, 9:35 pm	#1
gkargreen Triode Join Date: Nov 2006 Location: Fairfax, Virginia, USA. Posts: 25	Emor 200; mains transformer taps. Hi, all, I am repairing the above radio, and wanted to know what the taps in the mains transformer were marked for, thanks!

20th Nov 2006, 8:49 pm	#2
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: Emor Model 200 Radio help needed From memory the british models were tapped at 240/250-220-200 and neutral. Test the winding with an ohmeter. With the mains supply disconnected, all valves and tuning lamp removed apply 24(twenty four) volts AC across the primary (Winding with the highest dc resistance) and measure the voltages between neutral and the other taps. This should give you a clue. There will also be voltages on the secondary. If these are a factor of 10 less than normal you have a british/european transformer, if a factor of five the transformer is designed for US voltages. Similar test can be carried out with 12 volts AC, but of course if sec volts normal set is american etc. Or, the slightly unsafer method:-Remove all valves and dial lamps and apply 6 volts ac to 6v heater winding. Then measure voltage at primary. Easy!! Good luck. __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly." Last edited by Tim; 20th Nov 2006 at 9:06 pm.