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Old 30th Nov 2022, 3:36 pm   #6
DMcMahon
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Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Default Re: Truvox PD-95 R2R Check Out

Did a quick recording test using an old Grundig microphone that I have never used before.

Got a good recording signal on the recording level VU meter and could hear/monitor a good signal on headphones, but on playback of the recording just got total silence.

Because the VU meter gave good signal and could hear the record signal indicates that the record amplifier has some reasonable life and because the same circuitry (with different switching etc) is used for the playback amplifier, the playback amplifier probably is OK.

Do not yet know if Erase works, next need to check out the record bias and erase signals, the switched connections to the Play/Record head and the head itself.

The record level VU meter is the type where the meter needle sits at max reading (+3 red) on the right hand side of the meter and when switched to record the needle moves over towards the left side and then a zero set rotary control can be adjusted for meter reading of zero (0% / -20 on this meter).

First time hands on with this type of record level meter, have seen them before on machines like Ferrograph 4/5/6 Series.

David
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