Revox model 40 valve amplifier ELECTRONIC capacitor overhaul kit
Nagravox
Capacitor & Rectifier Upgrade Kit for Revox model 40 amplifier
This kit contains:
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replacement capacitors for the 3 large triple can (3 capacitors within 1 can) power supply electrolytics. 2 x HT and 1 x LT. Newly manufactured to fit as a perfect replacement.
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replacements for all other electrolytic capacitors.
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full set of 3 modern silicon bridge rectifiers
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piggy back PCB for 3 bridge rectifiers with appropriate dropper resistors complete with terminals and mounting pack.
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now also with special modification components to ensure better impedance matching as per later version and factory update bulletins.
Triple Can Motor Capacitors =3. X2 suppression caps = 6. Other capacitors = 3. Si diodes and rectifiers = 3. Resistors = 2. Full mounting kit for PCB + connection wire
The kit contains everything you will likely need to replace and upgrade those components that due to age have likely deteriorated.
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In house we MAKE the large triple can HT and LT capacitors ourselves using low leakage conservatively rated capacitance and working voltage electrolytic capacitors sourced from reliable OEM's. HT are rated 450 VDC and LT 50VDC. We also increase the capacitance slightly to provide improved power supply smoothing. (why - because its a prudent practice and will improve ripple, hum and noise). These capacitors fit directly in place exactly like the originals and the cases are fully insulated (the common -ve rail point is linked to the 4 mounting tabs)
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The audio signal path capacitors are specially selected low noise, low leakage / high stability types and fit in easily on the point to point wiring terminal board.
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A specially designed piggy back printed circuit board is provided with new silicon bridge rectifiers for the 3 power supplies. These replace the very suspect selenium rectifiers which should be replaced due to old age. CAUTION fumes given off by old selenium rectifiers when they go faulty are very toxic. The PCB mounts neatly simply drilling 3 x 3mm holes in the chassis. See the before and after pics below.
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As silicon rectifiers are more efficient than the old selenium type, a higher rectified output voltage results. This requires dropper resistors to limit working voltage back to normal values. These resistors have been carefully calculated, selected AND tested (mounted in situ on the PCB with the rectifiers) to reduce voltage on the model 40 to normal working levels.
Full instructions for each functional update section are included with pictures before and after detailing which components go where and a host of useful tips, checks and basic calibration.