theres only one way to rock-sammy.
listening to jvc tuner. jvc amp
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back to the inverse riaa board after my nap.
so i did some reading on google and even had some ai assistance....
this is where i started
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handy that it shows the end freq of the sweep and the level because that is what needs help.
target numbers:
* 20 Hz: -19.27 dB
* 50 Hz: -16.94 dB (The low turnover)
* 100 Hz: -13.09 dB
* 500 Hz: -4.75 dB
* 1,000 Hz (1 kHz): 0.00 dB (The center reference line)
* 2,122 Hz: +2.87 dB (The high turnover)
* 5,000 Hz (5 kHz): +8.21 dB
* 10,000 Hz (10 kHz): +13.73 dB
* 20,000 Hz (20 kHz): +19.62 dB
doing some reading and realized that i should set my hp8903b output impedance to 50ohm. so i did.
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that got me up to 18.88dB
so i then started working on the hi end capacitor and ended up adding a cap in parallel
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19.48dB is good enough for me. the hump at 100hz is gone. it was caused by a low input signal from the 8903b. i turned it up.)
there is a yellow trace under the blue one. they are tracking perfectly



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thatsa wrap. gonna put the lid on and stick some letters on it.