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Philco 39-30 shortwave sucks!
8/17/2005 3:08:45 PMElton
Hi all, this one works great on AM but will only recive a very small portion on the SW from about 12 to 14 MC and the rest is dead, I checked the SW coil and it apears to check out as far as the resistance I know philcos were notorius for corroded windings but this one looks good or could it be internal winding is bad? my schematic does not show what the resistance should be but it reads around 4 1/2 ohms, the band switch is good I phyisicaly removed the coil to look at it under a good light but could see nothing out of the ordinary any idaes out there? or does someone know what the proper resistance should be?
Thanks
ELton
8/17/2005 3:21:59 PMThomas Dermody
If the oscillator coil is broken, the radio will not work at all. If the antenna coil is broken, it may or may not work. Check for drifted resistors and leaky condensers. Check the alignment. It is possible that someone aligned the band to a harmonic instead of to the appropriate frequency, which is easy to do on short wave. I have this problem with my Crosley Super 11, only it is slightly different. The band doesn't pick up much S-W from about 14 to about 18 or 19, and then after that it picks up some. In this dead segment, however, it picks up harmonics of FM stations, which repeat over and over again. They are distorted, of course, since they are being detected with an AM detector (long explanation for the distortion). I haven't fixed the problem, yet, because I haven't had the time, and until now, I didn't have an accurate signal generator.

Thomas

8/21/2005 1:21:06 PMElton
Thanks Thomas I will check these items out , although my radio picks up nothing in the dead zone, not even any background noise it is almost like the radio is shut off it is so quiet.
:If the oscillator coil is broken, the radio will not work at all. If the antenna coil is broken, it may or may not work. Check for drifted resistors and leaky condensers. Check the alignment. It is possible that someone aligned the band to a harmonic instead of to the appropriate frequency, which is easy to do on short wave. I have this problem with my Crosley Super 11, only it is slightly different. The band doesn't pick up much S-W from about 14 to about 18 or 19, and then after that it picks up some. In this dead segment, however, it picks up harmonics of FM stations, which repeat over and over again. They are distorted, of course, since they are being detected with an AM detector (long explanation for the distortion). I haven't fixed the problem, yet, because I haven't had the time, and until now, I didn't have an accurate signal generator.
:
:Thomas
8/21/2005 2:23:23 PMNorm Leal
Hi Elton

Agree with Thomas, check alignment. It can be more critical on short wave.

Didn't notice antenna mentioned. Be sure to use an antenna for short wave.

Norm

:Thanks Thomas I will check these items out , although my radio picks up nothing in the dead zone, not even any background noise it is almost like the radio is shut off it is so quiet.
::If the oscillator coil is broken, the radio will not work at all. If the antenna coil is broken, it may or may not work. Check for drifted resistors and leaky condensers. Check the alignment. It is possible that someone aligned the band to a harmonic instead of to the appropriate frequency, which is easy to do on short wave. I have this problem with my Crosley Super 11, only it is slightly different. The band doesn't pick up much S-W from about 14 to about 18 or 19, and then after that it picks up some. In this dead segment, however, it picks up harmonics of FM stations, which repeat over and over again. They are distorted, of course, since they are being detected with an AM detector (long explanation for the distortion). I haven't fixed the problem, yet, because I haven't had the time, and until now, I didn't have an accurate signal generator.
::
::Thomas



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