I have repaired a Delco 3206 Farm Set. Output levels are very low however.
Input at the grids of the 4 output 48's is good but at the output of the same tubes the volume is unchanged.
Output voltages are correct.
Anode currents are correct.
Speaker and associated coil/transformers are correct.

It's a mystery.

Frank Doncaster England.

:
:I have repaired a Delco 3206 Farm Set. Output levels are very low however.
:Input at the grids of the 4 output 48's is good but at the output of the same tubes the volume is unchanged.
:Output voltages are correct.
:Anode currents are correct.
:Speaker and associated coil/transformers are correct.
:
:It's a mystery.
:
:
:Frank Doncaster England.

Frank,

Have you checked to make sure the field coil is energized (has magnetism) by touching a screwdriver or small steel rod to the center pole of the speaker while the radio is on? May try clipping a pm type speaker to the speaker leads and see if the sound is loud then. Possible mechanical problem with the speaker such as voice coil rubbing (not centered) or stuck from dust between it and the center pole.

Radiodoc

::
::I have repaired a Delco 3206 Farm Set. Output levels are very low however.
::Input at the grids of the 4 output 48's is good but at the output of the same tubes the volume is unchanged.
::Output voltages are correct.
::Anode currents are correct.
::Speaker and associated coil/transformers are correct.
::
::It's a mystery.
::
::
::Frank Doncaster England.
:
:Frank,
:
:Have you checked to make sure the field coil is energized (has magnetism) by touching a screwdriver or small steel rod to the center pole of the speaker while the radio is on? May try clipping a pm type speaker to the speaker leads and see if the sound is loud then. Possible mechanical problem with the speaker such as voice coil rubbing (not centered) or stuck from dust between it and the center pole.
:
:Radiodoc
:
Also Frank,

Have you measured for minus voltage on the grid of the 48 tubes (between grid and cathode)?

Radiodoc

Radiodoc.

Speaker fiels is fine. I will measure for -voltage and get back to you.

Thanks for your input so far

Frank Doncaster england

The Right Honourable and Esteemed Sir Frank Goddard Esq.

Three other queries:
1...How about the capacitive state of the line item # 50 capacitor.

2...If wires have been juggled about on the speaker /output transformer interfacing...any chance that there could be a phasing reversal between the output transformer and the field coil /voice coil relationship ?

3... Did the PM speaker sub into the Output transformers secondary confirm
any enhanced performance...volume / power wise ?

73's de Edd

Ok Boys. Lots to think about there. Today- Saturday - I am working away for 10 days. So the set stays on the bench till I get back.
I will post again say, Wednesday week after I have done all the checks.

Thanks again to you both.

Frank Doncaster England.