This auction is for ONE bare PCB. I created this PCB for a personal project. Originally I planned to buy the PS-1 designed by John Broskie. John designed the Aikido line stage and has some great power supplies. The PS-1 is a great power supply but it didn't have a few things I was looking for. I really wanted to get 6.3VDC regulated voltage out of 6.3VAC winding on my transformer and I wanted headroom for high current heater projects. I also wanted some options to use a choke with the high voltage. Those were deal-breakers for me and his boards couldn't give me what I needed. So I designed my own. I ended up with a great board and had plenty of extras made for fellow hobbyists.

• High Voltage: 50-400VDC @ 200mA
• Low Voltage: 2.5-12.6VDC @ 4.5A

Heater Circuit:

• Regulated 6.3VDC from 6.3VAC winding with the use of schottky diodes and super low dropout regulator. Or 5VDC from 5VAC, etc. This isn’t possible with almost every power supply out there.
• Voltage doubler jumper and trimpot adjustment. Allows for switching between 6.3V tubes and 12.6V tube without pulling out your soldering iron. Simply move the jumper and dial in the pot. A standard 6.3VAC transformer winding now allows the use of twice the tube choices. Go price a NOS 12SN7 vs a NOS 6SN7 and see how this board pays for itself.
• Huge capacitance for ultra-low ripple. 45,000uF capacitance.
• Full 4.5 amps of available heater current. High current components and heat management designed in. Large heat sink on LDO and heat sinks on all rectifying diodes. Remember you need 1.8X the DC current from your transformer. For example: to power 4 6SN7 tubes for a total of 2.4A, you need a theoretical bare minimum of 4.32A available from your transformer. A safer rule of thumb is 2.0X the DC current. If you're using the doubler, then current gets cut in half once more (darn that Ohms law).
• Two sets of heater outputs.

High Voltage Circuit:

• Regulated output using Maida circuit.
• Huge capacitance for ultra-low ripple. 256uF capacitance.
• Accepts multiple configurations. Full wave bridge, tube rectifier, or full wave center tap.
• Allows for external choke filter (C-L-C) or 5W voltage dropping resistor (C-R-C).
• Two sets of B+ outputs.

Additional Features:

• ¼ B+ reference circuit built in. Elevates the heater ground to ¼ of the B+ voltage. Provides for hum free power and cathode protection.
• House ground isolation circuit built in. Chassis and House ground attach to the board for a hum free experience.
• A jumper location is provided to ground directly through one of the mounting screws for the chassis ground. Or wire the chassis ground traditionally with the provided wire pad.
• Designed for use with high end audio grade components (Wima MPK series, Nichicon KX and KW series, etc).
• Small and compact. All this circuitry is smartly arranged on a 4" X 6.25" board.
• Thick PCB with 2 ounce traces.

A BOM from Mouser is below. I used all high end components (Wima and Nichicon Audio caps, etc). Full schematic and board layout are above. If you're handy you can wire one up point to point with all the info in this add and skip the need to buy the PCB. Please know your skill level and knowledge of electronics before considering this PCB. If Mouser is out of something try DigiKey. You should be comfortable specifying substitutions. I do my best to keep the direct link BOM updated. Note main picture shows a slightly different revision but with exact same schematic.

Mouser direct link for Pre-Amp PS BOM

LIABILITY DISCLAIMER

A person who constructs or works on electronic equipment may be exposed to hazards, including physical injury, the risk of electric shock or electrocution, and exposure to hazardous substances such as lead, mercury, and other inorganic or organic compounds.  These hazards can result in health problems, injury, or death.  Only qualified persons who understand and are willing to bear these risks themselves should attempt the construction of electronic equipment.  By purchasing this item, the buyer acknowledges these risks.

Vacuum tubes operate at high temperatures, may contain toxic substances, and may have exposed parts that carry hazardous voltages.  There is a risk of electric shock, electrocution, burns, or fires that is inherent in the construction and use of vacuum tube equipment.  By purchasing this item, the buyer acknowledges these risks.

IN NO EVENT SHALL THE SELLER BE LIABLE FOR ANY SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY NATURE including, but not limited to, property damage, personal injury, death or legal expenses. Buyer's recovery from Seller for any claim shall not exceed the purchase price paid by Buyer for the goods, irrespective of the nature of the claim, whether in warrant, contract or otherwise. By purchasing this item, BUYER AGREES TO INDEMNIFY, DEFEND AND HOLD SELLER HARMLESS FROM ANY CLAIMS BROUGHT BY ANY PARTY REGARDING ITEMS SUPPLIED BY SELLER AND INCORPORATED INTO THE BUYER'S PRODUCT.

If you do not agree to this disclaimer, DO NOT BUY THIS ITEM.