Upon opening a Teac HDD-160T digital video recorder revealed that C41 (+12V before inductor) has bulged, along with C21 (+5V digital, not HDD) being discoloured (Both were Samxon GF series 
, and there were seven other such units).
This power supply only monitored the +5V (digital) rail, which means if C21 or C22 go bad the output on the +12V (the +12V HDD rail is regulated) could go abnormally high, possibly damaging the AK4702 DAC and SCART switch, along with the hard drive in the right circumstances.
In some power supplies (including some Topfield units), two or more rails are monitored, and if one or more go abnormally high, the +5V or +3.3V rail would go down, causing non-damaing malfunctions until the power supply capacitors are replaced (this happened in a TF5000PVRt, with intermittent problems with the hard drive is accessed, especially when it is trying to spin up
), unlike the Teac unit mentioned earlier 
.
If you have such a model, replace ALL of the electrolytic capacitors (I prefer Chemi-Con KY, or KZM if you can get them) before catastrophic damage occurs when the Samxon GF capacitors in the power supply go bad.
, and there were seven other such units).This power supply only monitored the +5V (digital) rail, which means if C21 or C22 go bad the output on the +12V (the +12V HDD rail is regulated) could go abnormally high, possibly damaging the AK4702 DAC and SCART switch, along with the hard drive in the right circumstances.
In some power supplies (including some Topfield units), two or more rails are monitored, and if one or more go abnormally high, the +5V or +3.3V rail would go down, causing non-damaing malfunctions until the power supply capacitors are replaced (this happened in a TF5000PVRt, with intermittent problems with the hard drive is accessed, especially when it is trying to spin up
), unlike the Teac unit mentioned earlier .If you have such a model, replace ALL of the electrolytic capacitors (I prefer Chemi-Con KY, or KZM if you can get them) before catastrophic damage occurs when the Samxon GF capacitors in the power supply go bad.
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