[Jukebox-list] Re: Rock Olga 1428

On 2024/07/01 12:02 p.m., ascott822 via Jukebox-list wrote:

Sound went out suddenly on my 1428.  The amp has been re-capped and tubes replaced 3 years ago. Wondering if there is a mute switch I might could check and it’s location.

I don't think this machine had a mute, instead it warmed up really fast using a higher voltage for the tube filaments until the 5U4 got warm enough that the HV would activate the heater voltage reduction relay.

Are all the tubes glowing? A bad 5U4 will cause a total lack of sound.

Do you hear any humming from the speaker? If the speaker has a field coil is it warm after around 1/2 hour? That will indicate that the 5U4 and it's HV is working.

John :-#)#