DYNACO PAT-5 Руководство по сборке - Страница 18

Просмотреть онлайн или скачать pdf Руководство по сборке для Усилитель DYNACO PAT-5. DYNACO PAT-5 18 страниц. Replacement power supply rev e hardware

 U3 – 82 degrees C

 Q2 – 92 degrees C

Even the hottest device, Q2, has a junction temperature that is 125-92=33 C below the

maximum recommended operating junction temperature. It is 58 C below the Absolute

maximum operating junction temperature. The temperatures observed will decrease for

loads less than 100 mA.

Typically, the worst-case load is for the combination of the improved line stage boards

(16 mA per board, 32 mA for both boards) and the upgraded phono preamp (22.5 mA per

board, 45 mA for both boards), for a total of 77 mA load on each of the plus 15 and

minus 15 volt rails.

A spectrum analysis of the noise at full load shows very low noise. Note that -120 dBV is

the equivalent of 1 micro-volt:

+15V

 -105 dBV @ 60 Hz

 -110 dBV @120 Hz (equivalent to 39.8 microvolts)

 -110 dBV @ 240 Hz

 Noise typically drops below -120 dBV above 2 kHz

+42V

 All power line harmonics <-103 dBV (noise floor in that region

 Noise typically drops below -120 dBv above 1 kHz

-15V

 -105 dB @ 60 Hz

 -110 dB at @120 Hz

 Noise typically drops below -115 dBV at 300 Hz and above

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