Kits!

mrarroyo wrote: oqvist, Graham is working on a kit to convert the silver cased Solo's to Solo SRG. It is not out yet.

Now available here:

http://www.headphoneamplifiersusb.com/solosrgiiupgrade.htm

Jon


Edited by jonclancy - 22 Dec 2009 at 11:21am

looking forward to the new e-comerce site. It will really enable you to simplify the process and cut out the middleman reseller a bit.

The circuit isn't all that different from other proposed linear regulators. Basically it is what you see on the LM350 data sheet (https://www.onsemi.com/pub/Collateral/LM350-D.PDF fig. 20).

The LM350 has been around since about 1980 (https://ia800703.us.archive.org/0/items/NationalSemiconductorVoltageRegulatorHandbook1980/NationalSemiconductorVoltageRegulatorHandbook1980.pdf page 10-93), and has been used in a colossal number of circuits.

To get 3 amps continuous out of it requires some care about heatsinking, balancing it with ripple voltage so that with all rated mains voltages reasonably good load regulation is achieved without ripple breaking through.

Load regulation can never be as good as quoted for the device because wiring drops voltage. The constructor might wish to experiment by taking the adjustment feed from the output terminals if perfection is required.

There are overvoltage crowbars on both outputs (5V and 3V3) should the voltage regulator outputs exceed the set voltages. This would obviously signal a faulty regulator or adjustment circuit fault.

The current state of play can be seen here: https://www.hifisystemcomponents.com/forum/5v-3a-psu_topic4221_post59767.html#59767

I am waiting seeing the finished casework from the metalworking supplier. It seems to be taking an awfully long time, but that's the UK for you...