I am near the finish line on the restoration of this Marconi Model 187.

Replaced all caps, some resistors, cleaned the switch assembly, cleaned the tuning capacitor, replaced the speaker with a PM type, installed a choke and a resistor to replace the field coil, rejuvenated the bias cell, replaced the volume control, did an alignment on all 5 bands and set the pre-set stations.

The radio works great with one exception:

On very strong stations there is little to no control of the volume. It seems that it is either too loud or not loud enough.

Here's what I don't know,

Could this be an AVC issue?
Or is this an audio taper vs linear taper issue?

I'm not sure, but I think the replacement volume control was an audio taper.

I have double checked the bias cell and it is still measuring 1.2 volts.

Thoughts anyone?
Gary

If the control is adjusting input to 1st audio amplifier grid it's usually 500K or 1 meg, audio taper.

AVC reduces signal strength on strong stations but your volume control should still give proper adjustment. It should not jump from too low to too high. This indicates a bad spot in carbon element of the control.

Norm

:OK here's what I know:
:
:I am near the finish line on the restoration of this Marconi Model 187.
:
:Replaced all caps, some resistors, cleaned the switch assembly, cleaned the tuning capacitor, replaced the speaker with a PM type, installed a choke and a resistor to replace the field coil, rejuvenated the bias cell, replaced the volume control, did an alignment on all 5 bands and set the pre-set stations.
:
:The radio works great with one exception:
:
:On very strong stations there is little to no control of the volume. It seems that it is either too loud or not loud enough.
:
:Here's what I don't know,
:
:Could this be an AVC issue?
:Or is this an audio taper vs linear taper issue?
:
:I'm not sure, but I think the replacement volume control was an audio taper.
:
:I have double checked the bias cell and it is still measuring 1.2 volts.
:
:Thoughts anyone?
:Gary