TWO Defective RCA TVPRAMP1 Preamps
My first RCA TVPRAMP1R preamp had these measurements:
Voltage out of power inserter without preamp: 19.5 VDC
Voltage with preamp connected: 9.5 VDC
Load current: 70 mADC
Gain 23 db
I thought it was strange that the voltage out with no load was so high because the power inserter contains a voltage regulator, but it worked.
Recent measurements of first TVPRAMP1R:
No load voltage: 13.5 VDC
Voltage under load: 7.37 VDC
Load current: 18 mADC
Gain: 0 dB; Uh-Oh!
Second (new) TVPRAMP1E measurements:
No load voltage: 9.11 VDC
Voltage to preamp under load: 9.11 VDC
Load current: 75 mADC
well, that looked good so far, but
Gain: 5 dB; not so good
I thought there was something wrong with my signal level meter, so I substituted a CM7777HD at low gain:
Gain: 17 dB; right where it should be.
My meter is OK, the RCA preamp isn't OK.
I can't recommend the RCA TVPRAMP1 preamp.
Last edited by rabbit73; 2-Nov-2018 at 9:58 PM.
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