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Item Specifics - Amplifiers
Type:
Power Amplifiers
Brand:
Quad
Condition:
New
New Philips 15 Volt Zener Diodes For Quad 405-1 Power Boards.
High quality audio grade components.
Simple new for old replacement.
Instructions for pcb 12368 issues 6 and 9 via email.
Sensible upgrade to compliment modern 15 volt opamps ie - 134/604.
Brand New , Fresh stock and Unused.
Supplied in ESD foil protective pack.
These four diodes are sufficient for one Quad 405-1.
One off to replace D1 12 volt.
One off to replace D2 12 volt.
Two diodes are used in each of the two boards.
Pcb will have to be removed if other than 12368 issues 6 and 9.
Quad 405-1 before serial number 29000 were produced with D1,2 of 12 volts.
Pcb 12368 issue 9 overlaps s/n 29000 so these could be 12v(earlier) or 15v(later).
Potential customers are respectfully advised to check thier D1,2 before purchase.
Optimal performance of say the Burr Brown Texas opa 134/604 occurs at 15 volt supplies.
In this case changing to a modern 15 volt diode gives two advantages.
Fistly the new diode is technically superior to the old.
Secondly providing 15 volts allows the opamp to perform at its best.
Quad fitted 15 volt zeners to 405-1 s/n 29000 onwards and all 405-2.
Small level hf sounds which create soundstage depth are better crafted.
Improvements are noticed in higher frequencies giving more space and realism.
Information about antistatic precautions.
Touching/earthing at least two component wires/contacts at once
whilst you have a static surplus will damage diodes.
Touching water taps, pipes or radiators readily discharges static.
Using insulated pliers avoids completing the static circuit with your hands.
Antistatic wristbands are a good investment.
Combined postage available when buying several items. The highest postal fee of your items is the single fee you pay.
[BuyItNow] > [Continue Shopping] for each item you require Then await combined invoice from seller
Possible Upgrades For Printed Circuit Boards
12368 issue 5, or 6, 7
diode 4003 & resistor 75R , diode 4148 , zener 15v , resistor 10R 2w ,
opamps , input gain reduction , 405-1 board capacitors
12368 issue 9 with serial number below 29000
diode 4003 & resistor 75R , diode 4148 , zener 15v , resistor 10R 2w ,
opamps , input gain reduction , 405-1 board capacitors
12368 issue 9 with serial number above 28999
12368 issue 10 and 12565 issue 3
diode 4003 & resistor 75R , diode 4148 , resistor 10R 2w ,
opamps , input gain reduction , 405-1 board capacitors
12565 issue 5
diode 4003 & resistor 75R , resistor 10R 2w ,
opamps , input gain reduction , 405-2 board capacitors
12565 issue 6 and issue 7
resistor 10R 2w ,
opamps , input gain reduction , 405-2 board capacitors
Issue numbers are marked on the printed circuit boards.
Serial number silver plate is to the rear of the
base plate in the centre.
QUAD 405-1 AMPLIFIER ZENER DIODES 15 volt on eBay, also Power Amplifiers, Amplifiers, Home Audio Hi Fi, Consumer Electronics (end time 18-May-08 22:51:29 BST) Check if QUAD 405-1 AMPLIFIER ZENER DIODES 15 volt is for sale as immediate purchase or as an auction item, and use PayPal for free protection on your purchases.
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