Home  Resources  References  Tubes  Forums  Links  Support 
philco 40-190 magnetized chassis
3/2/2004 10:58:32 PMmanuel
hello, im working on a philco 40-190 and radio has a hum. i replaced the electrolityc caps and radio continues with hum i noticed that chassis and speaker frame is magnetized with radio on off and unplugged. i tried grounding radio and it has not helped. thank you for info
3/2/2004 11:22:22 PMNorm Leal
Hi Manuel

Notice negative of electrolytic filter caps do not connect to the same place. One cap connects between cathode of your 84 tube and center tap of high voltage winding on your power transformer, not chassis.

Original caps were 12 & 16 mfd. You could use 22 mfd @ 450 volts for replacement.

Is the hum there with volume down?

Speaker frame being magetized, not a problem.

Norm

:hello, im working on a philco 40-190 and radio has a hum. i replaced the electrolityc caps and radio continues with hum i noticed that chassis and speaker frame is magnetized with radio on off and unplugged. i tried grounding radio and it has not helped. thank you for info

3/2/2004 11:41:08 PMmanuel
:Hi Manuel
:thank you norm, i connected ground to chassis ill have to connect to green wire, i belive this radio was serviced 40 years ago and i was following what was there thank you once again
: Notice negative of electrolytic filter caps do not connect to the same place. One cap connects between cathode of your 84 tube and center tap of high voltage winding on your power transformer, not chassis.
:
: Original caps were 12 & 16 mfd. You could use 22 mfd @ 450 volts for replacement.
:
: Is the hum there with volume down?
:
: Speaker frame being magetized, not a problem.
:
:Norm
:
:
:
::hello, im working on a philco 40-190 and radio has a hum. i replaced the electrolityc caps and radio continues with hum i noticed that chassis and speaker frame is magnetized with radio on off and unplugged. i tried grounding radio and it has not helped. thank you for info
3/3/2004 11:25:33 AMNorm Leal
Hi Manuel

If you don't already have it, the schematic can be found here:

http://www.nostalgiaair.org/PagesByModel/339/M0013339.pdf

Norm

::Hi Manuel
::thank you norm, i connected ground to chassis ill have to connect to green wire, i belive this radio was serviced 40 years ago and i was following what was there thank you once again
:: Notice negative of electrolytic filter caps do not connect to the same place. One cap connects between cathode of your 84 tube and center tap of high voltage winding on your power transformer, not chassis.
::
:: Original caps were 12 & 16 mfd. You could use 22 mfd @ 450 volts for replacement.
::
:: Is the hum there with volume down?
::
:: Speaker frame being magetized, not a problem.
::
::Norm
::
::
::
:::hello, im working on a philco 40-190 and radio has a hum. i replaced the electrolityc caps and radio continues with hum i noticed that chassis and speaker frame is magnetized with radio on off and unplugged. i tried grounding radio and it has not helped. thank you for info



© 1989-2025, Nostalgia Air