01-12-2021, 07:45 PM
I'm returning to this radio for a couple of reasons.
1) Mrs H wants to be able to play records (33rpm LPs for the most part), and purchased a small turntable that will fit in place of the 78 RPM changer.
2) The power transformer runs hot, and I would like to know why. This could be as simple as arranging to reduce the line voltage, but I'd like a definite explanation.
To begin with, we'll tackle the first question. Since the phono was via the Zenith "Cobra" design, there is a connector on the chassis that takes an audio input. It has 8 pins in the pattern of an octal socket, but also a pin in the centre space, offset to ensure correct orientation. While I could use the connector from the small pre-amp chassis, I rewired the whole thing and would prefer not to mess with it. So, I have another plan - take an octal plug, remove the spigot, and add the offset pin. The Octal plug I found on-line looks to have enough material in it to support a pin in a suitably sized hole. I can use the socket as a template to get the location. No electrical connection is required from the pin for this application. The only thing I have not checked precisely is that the regular 8 pins are exactly octal pattern, but they looked very close.
With a working plug, I just need to combine the L+R channels from the new record player, and perhaps include some attenuation, since the Zenith's input seems very sensitive.
Cheers,
Ed
1) Mrs H wants to be able to play records (33rpm LPs for the most part), and purchased a small turntable that will fit in place of the 78 RPM changer.
2) The power transformer runs hot, and I would like to know why. This could be as simple as arranging to reduce the line voltage, but I'd like a definite explanation.
To begin with, we'll tackle the first question. Since the phono was via the Zenith "Cobra" design, there is a connector on the chassis that takes an audio input. It has 8 pins in the pattern of an octal socket, but also a pin in the centre space, offset to ensure correct orientation. While I could use the connector from the small pre-amp chassis, I rewired the whole thing and would prefer not to mess with it. So, I have another plan - take an octal plug, remove the spigot, and add the offset pin. The Octal plug I found on-line looks to have enough material in it to support a pin in a suitably sized hole. I can use the socket as a template to get the location. No electrical connection is required from the pin for this application. The only thing I have not checked precisely is that the regular 8 pins are exactly octal pattern, but they looked very close.
With a working plug, I just need to combine the L+R channels from the new record player, and perhaps include some attenuation, since the Zenith's input seems very sensitive.
Cheers,
Ed
I don't hold with furniture that talks.
