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testing osc. coil for continuity
12/9/2007 8:58:41 PMBrian
I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?

thanks

12/9/2007 9:05:44 PMNorm Leal
Brian

Philco 38-38 which should be the same as 37-38 shows the oscillator coil with 4 wires. These connect to two sets of coils. Each set with continuity.

Which coil have you removed? Some coils have an extra connection at the bottom soldered to chassis?

http://www.nostalgiaair.org/PagesByModel/248/M0013248.pdf

Norm

:I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?
:
:thanks
:

12/9/2007 9:31:53 PMBrian

It is the broadcast coil that I removed (range 1) but I don't see a 4th connection?

:Brian
:
: Philco 38-38 which should be the same as 37-38 shows the oscillator coil with 4 wires. These connect to two sets of coils. Each set with continuity.
:
: Which coil have you removed? Some coils have an extra connection at the bottom soldered to chassis?
:
: http://www.nostalgiaair.org/PagesByModel/248/M0013248.pdf
:
:Norm
:
:
:
:
:
::I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?
::
::thanks
::

12/10/2007 1:24:13 AMNorm Leal
Brian

Do you have continuity between the three wires? Sometimes the connection to chassis has a wire? If you don't have continuity between the three wires does one read to a mounting lug?

Norm

:
:It is the broadcast coil that I removed (range 1) but I don't see a 4th connection?
:
::Brian
::
:: Philco 38-38 which should be the same as 37-38 shows the oscillator coil with 4 wires. These connect to two sets of coils. Each set with continuity.
::
:: Which coil have you removed? Some coils have an extra connection at the bottom soldered to chassis?
::
:: http://www.nostalgiaair.org/PagesByModel/248/M0013248.pdf
::
::Norm
::
::
::
::
::
:::I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?
:::
:::thanks
:::

12/11/2007 6:09:16 AMBrian
I believe I now have a working oscillator, by touching grid cap of 1C7 and touching the tuner capacitor I get large volume on AM stations. and negative 8 volts on grid of 1C7. Is it my antennna circuit now ?

:Brian
:
: Do you have continuity between the three wires? Sometimes the connection to chassis has a wire? If you don't have continuity between the three wires does one read to a mounting lug?
:
:Norm
:
::
::It is the broadcast coil that I removed (range 1) but I don't see a 4th connection?
::
:::Brian
:::
::: Philco 38-38 which should be the same as 37-38 shows the oscillator coil with 4 wires. These connect to two sets of coils. Each set with continuity.
:::
::: Which coil have you removed? Some coils have an extra connection at the bottom soldered to chassis?
:::
::: http://www.nostalgiaair.org/PagesByModel/248/M0013248.pdf
:::
:::Norm
:::
:::
:::
:::
:::
::::I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?
::::
::::thanks
::::

12/11/2007 11:19:13 AMNorm Leal
Brian

The oscillator is operating if you can tune in different stations. If you recive only one, or a mix of stations but can't tune the oscillator isn't operating.

If touching top of the 1C7 causes the radio to receive stations properly problem before this tube. Most likely in the antenna circuit.

Norm

:I believe I now have a working oscillator, by touching grid cap of 1C7 and touching the tuner capacitor I get large volume on AM stations. and negative 8 volts on grid of 1C7. Is it my antennna circuit now ?
:
::Brian
::
:: Do you have continuity between the three wires? Sometimes the connection to chassis has a wire? If you don't have continuity between the three wires does one read to a mounting lug?
::
::Norm
::
:::
:::It is the broadcast coil that I removed (range 1) but I don't see a 4th connection?
:::
::::Brian
::::
:::: Philco 38-38 which should be the same as 37-38 shows the oscillator coil with 4 wires. These connect to two sets of coils. Each set with continuity.
::::
:::: Which coil have you removed? Some coils have an extra connection at the bottom soldered to chassis?
::::
:::: http://www.nostalgiaair.org/PagesByModel/248/M0013248.pdf
::::
::::Norm
::::
::::
::::
::::
::::
:::::I've removed one of coils from my Philco 37-38, the coil has three wires. Are there continuity checks between these 3 wire connections I can make?
:::::
:::::thanks
:::::



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