Geo wrote in message
news
On Wed, 14 Jan 2009 14:09:27 -0000, "N_Cook" wrote:

Normal or abnormal ?
Came in for an intermittant problem, fixed, and the following the owner
lives with but is it normal or abnormal?
With feed into a "normal" input and the "brilliant volume" at zero then
there is no control of the bass on the tone control, you need to have a
little advance on the brilliant volume.
Trouble around V7 ECC83 ?
DC voltages cathode,grid,anode
"brilliant half" 0,1.4V, 182V
"tone half" 182,183,290V
all associated pots ,Rs and Cs check out agreeing with schematic as does
the
valve and same Vs with a different valve

Assuming I am looking at the correct circuit - the bass control is in the
output
of the brilliant circuit only. The "brilliant" and "normal" are mixed at
the
junction of the 220k resistors so the bass control will have no effect on
the
normal channel.
The brilliant volume control effectively grounds the grid of V7a so I
would
expect 0v there and 1.5v ish on the cathode.

--
Geo

So normal, in summary, for this amp?
The "brilliant" half is upper in this section of schematic
http://home.graffiti.net/diverse:graffiti.net/vox1.jpg

There is treble control but not bass control with "normal" input and zero on
brill vol.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/