DYNACO PAT5PWR Assembly Manual - Page 11

Browse online or download pdf Assembly Manual for Amplifier DYNACO PAT5PWR. DYNACO PAT5PWR 18 pages. Replacement power supply rev e hardware

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470 µF

C10

470 µF

C11

470 µF

Check your work

Look over the board to verify that:

1. All components are soldered.

2. No solder bridges are apparent.

3. Polarity of the electrolytic capacitors is correct.

4. The right regulator is in the right location.

5. The heatsink hardware is tight.

6. Diode polarity is correct.

If everything looks good, you're ready to install the power supply into your PAT-5.

Checking the preamp and old power supply

For these steps, use your soup bowl to safely store the mechanical parts you'll remove as

you disassemble and re-assemble your PAT-5.

This section assumes that the original power supply and preamp was nominally working,

We'll measure the original voltages to confirm that assumption. Here are the steps.

Checking the preamp and old power supply

Pull the Preamp's AC plug and wait 1 minute before going on.

Remove the four black slotted-head screws, 2 on each side of the preamp,

that hold the top cover in place.

Remove the one screw from the center of the back of the top cover.

Remove the cover and set it aside.

Set your meter to DC volts.

Make sure that your PAT-5 is completely disconnected from any other

equipment.

Plug the PAT-5 into the AC power socket. Note: There are potentially lethal

voltages inside the PAT-5 from the instant it is plugged in, regardless of the

state of the ON-OFF switch!

Measure the voltage from eyelet 4 to eyelet 1. It should be 42.5 Volts, plus

or minus 3 Volts.

Measure the voltage from eyelet 3 to eyelet 1. It should be 15 Volts, plus or

minus 1.5 Volts.

Measure the voltage from eyelet 7 to eyelet 1. It should be -15 Volts, plus or

minus 1.5 Volts.

Voltages outside of the indicated range may indicate a problem with the original power

supply. Voltages less than the indicated amount (for example, if the -15 measured only -

3) might indicate either a problem with the original power supply, or a problem with the

PAT-5 circuits. If you have that condition, the next few instructions well help you sort it

out.

Electrolytic capacitor, 470 µF 100 V, radial leads

Removing the cover

Measure the voltages

Page 11 of 18

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