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snowman_al · 22nd Jun 2019, 3:00 pm

Umm,
The component under the black ERG resistor is a 'thermal delay'.
The thermal delay works from the same 11.5 volt ac winding on the transformer as the 'power' lamps. It is there to lessen the 'thump' you get when you power the amplifier up, nothing else.
Until the delay 'switches' over the whole amplifier current goes via the black ERG resistor (47 ohms I think). If the delay does not switch over, the black resistor continues to take the total current and will surely glow as you turn the volume up... and probably cause the loss of power and distortion too. The spark you see might be the contacts arcing?

When you fixed the power on lamp did you alter or dislodge anything?
Was it working correctly before you changed the caps?

Alan

22nd Jun 2019, 3:00 pm	#5
snowman_al Octode Join Date: Dec 2018 Location: Llandeilo, West Wales, UK. Posts: 1,092	Re: Armstrong 626 high volume problems Umm, The component under the black ERG resistor is a 'thermal delay'. The thermal delay works from the same 11.5 volt ac winding on the transformer as the 'power' lamps. It is there to lessen the 'thump' you get when you power the amplifier up, nothing else. Until the delay 'switches' over the whole amplifier current goes via the black ERG resistor (47 ohms I think). If the delay does not switch over, the black resistor continues to take the total current and will surely glow as you turn the volume up... and probably cause the loss of power and distortion too. The spark you see might be the contacts arcing? When you fixed the power on lamp did you alter or dislodge anything? Was it working correctly before you changed the caps? Alan __________________ Never Leave Well Enough Alone...