New valve phono preamp build

[g8ina]

Valve RIAA preamp build. Single reused case (was a Skytec 150wpc Power Amp) will have new front and rear panels and top cover will be resprayed. Transformer was a couple of quid off a car boot. Power supply is on Veroboard, its been a while but still surprisingly easy to use. Centre screen plate separates PSU from main amp board. Phono inputs, BNC outputs. Particular attention will be placed on grounding, will also use a screened mains cable.

An ebay company listed black powder coated aluminium sheets and cut to size at no extra cost. Only trouble is they arrived in plain anodised ali, NOT black powder coated

More pics added, I managed to build this entire thing, wire it all up, switch it on, and it all worked first time ! Rather amazed and proud of myself ! Note the switch on protection system

285vdc HT and 12.3VDC heaters, used a LM338 to regulate the 12v line, adjustable between 11.5 and 13.5vdc.

[Zak33]

shame about the ebay miss-listing of powder coated!

But still... what a build.

I'd have no idea where to start.

Love the plastic tub covers

[DanceswithUnix]

At Uni we had to make a battery charger as a 1st year project, and as part of that we made a case for it by bending sheet metal with something like:

https://www.amazon.co.uk/165150-Bend...dp/B01N0CPI1Y/

[g8ina]

ebay seller apologised and has sent replacements. My bad on heater voltages, should be 12.6 not 12.3

[Zak33]

At Uni we had to make a battery charger as a 1st year project, and as part of that we made a case for it by bending sheet metal with something like:

https://www.amazon.co.uk/165150-Bend...dp/B01N0CPI1Y/

now THAT is in my basket!!!!