Hey all,
I've got this SONY Under Cabinet Radio. Model # ICF-CD523.
Over the years the FM reception has really gone down hill. I would like to try and fix this. I opened up the radio and found the FM Chip CXA1960Q. From Pin #18 we go through a 26Ω resistor (R6) and then it goes out to a BPFI (GFWE2 SE). The input of this 3 pin device is fed from a cap (C953, 200pF).
The other side of this cap goes to the secondary side of the step down transformer. So basically they are using the power cord as an antenna (as it is well known).
I checked the resistor and the cap, and they are good.
I can't check the BPFI unless I pull it and test it using a scope and oscilliscope... I'm sure there are other ways.. Anyways...
Refer to the attched schematic I made up. I basically cut the antenna from going through the transformer. and then soldered in a new wire at the point shown. The wire is then fed through the enclosure and I tried running the wire at different lengths and directions.
Because the outlet is right behind the radio, I cut 4 feet off the cord.
Overall, this did improve things... but some stations still have some static.
But a couple stations do not come in clear. 100.5 for example.
Other radios in the home play 100.5 quite clear.
I'm also surprised I can hear 100.5 in the back ground of a 97.5 station.
Any thoughts... suggestions??
Do I have my antenna wrong? Or is the chip CXA1960Q semi pooched?
I've got this SONY Under Cabinet Radio. Model # ICF-CD523.
Over the years the FM reception has really gone down hill. I would like to try and fix this. I opened up the radio and found the FM Chip CXA1960Q. From Pin #18 we go through a 26Ω resistor (R6) and then it goes out to a BPFI (GFWE2 SE). The input of this 3 pin device is fed from a cap (C953, 200pF).
The other side of this cap goes to the secondary side of the step down transformer. So basically they are using the power cord as an antenna (as it is well known).
I checked the resistor and the cap, and they are good.
I can't check the BPFI unless I pull it and test it using a scope and oscilliscope... I'm sure there are other ways.. Anyways...
Refer to the attched schematic I made up. I basically cut the antenna from going through the transformer. and then soldered in a new wire at the point shown. The wire is then fed through the enclosure and I tried running the wire at different lengths and directions.
Because the outlet is right behind the radio, I cut 4 feet off the cord.
Overall, this did improve things... but some stations still have some static.
But a couple stations do not come in clear. 100.5 for example.
Other radios in the home play 100.5 quite clear.
I'm also surprised I can hear 100.5 in the back ground of a 97.5 station.
Any thoughts... suggestions??
Do I have my antenna wrong? Or is the chip CXA1960Q semi pooched?
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