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FS: Lomo resistance-transformer-coupled amplifier

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sanjok

Member
Joined
Nov 3, 2013
Messages
10
Location
Moscow
Hi. I have for sale Lomo high gain preamps from master type recorders.
It is fully discrete except 1 IC in vu meter circuitry.
Needs 33 vdc to run.

Playback amplifier 71U-15 is designed to amplify and
correction of audio signals coming from the magnetic
playback head with an inductance of 60 to 90 mH

TECHNICAL DATA

The gain at a frequency of 400 Hz, dB:
maximum, at least 72
minimum, not more than 52
The input voltage at a frequency of 400 Hz, mV:
Rated 1.55
maximum, at least 17
The output voltage in the range of frequencies from 21.5 to 16,000Hz,
Rated 1.55
maximum, at least 5
Load resistance, Ohm, not less than 600
Distortion in the range
frequencies from 31.5 to 16,000 Hz at maximum gain,
maximum level of output voltage and rated
correction,%, not more than 0.5

Noise level, measured relative to the nominal output
voltage gain 66 dB and a nominal correction, dB,
not more than minus 62
The noise level, measured along the curve "A" dB
not more than minus 72

Voltage, in 33 +/- 0.75

Modules in good working condition. With some modification it can become microphone preamps.
Have no schematics. 71U-15 is Y1 in wiring diagram (see pics)
Input transformer Pic 4 (second from bottom)
400$ per 2  modules + shipping.
PM me.

http://postimg.org/gallery/1twqug6w/9f779eb4/
 
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