Я4С-89

The Я4С-89 is a plug-in for Soviet 7000-series clones which contains a pulse generator. It is intended for use with the sampling plugins in a similar manner to the Tek S-52 pulse generator head. It can free-run or take a 5 V external trigger signal.

The pulse outputs require an external pulse shaping cable in order to be useful. The cables contain a 1И308К 50 mA tunnel diode.

From the top, the connectors are:

• external 5 V (TTL) trigger in
• sync output, variable level and polarity
• positive-going pulse output
• negative-going pulse output

The buttons are:

• manual trigger
• external trigger mode
• period 1/0.1/0.01 ms
• delay 25/50/100/200 ns (can be added by pressing multiple buttons)
• pulse width 0.01/0.2 μs

The rotary controls are:

• external trigger level
• period vernier
• sync output amplitude, negative-zero-positive
• delay vernier
• pulse width

then two screwdriver bias adjustments for the positive-going and negative-going pulse outputs.

The connectors are СР50-73 type, which are almost compatible with BNC connectors but the latch is a tight fit and the centre contact can be unreliable.

Key Specifications

Period	10μs to approx 15 ms, or external trigger
Post-trigger delay	0 to approx 400 ns
Rise time	Depends on external pulse shaper
Pulse width	10 ns to 10 μs in two ranges
Trigger output amplitude	−5 V to +5 V into 1 MΩ, −1 V to +1 V into 50 Ω
Pulse output amplitude	200 mV or 400 mV depending on pulse shaper

Pictures

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  Front

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  Threequarter view

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  Pulse shaper cables schematic