QL564 TTi power supply

[RogerThat]

I couldn’t find any post on this power supply so here comes some pictures and impressions.

The mechanical construction is nothing special, bent steel(no sharp corners) with self taping screws on the lid. Plastic feels like ordinary cheap plastic. Buttons has a bit soft click but the rotary is fine. The rotary can be spun fast using the indent. It can step either 1/10/100mV and 1/10/100mA per step. Voltage and current limit can be set using the numerical keypad also.

The unit starts in a few seconds and the output is off by default. The output on/off is via a transistor and not relay. When turning the unit on or plugging the unit in with power switch set on, there are a few short spikes, see scope pictures.

I tried measuring noise using my Rigol 1054z. Probe set to 1x, BW limit to 20Mhz. Scope noise is 3mVPP and connected across my resistor it shows around 8mVPP.

I was surprised to find guard traces on the PCB. The main DIL package with guards is a 1 to 8 MUX(HEF4051BP) with the 1 connected to a 16bit DAC(MAX5441).

And, the pictures.

[RogerThat]

And scope pictures

This shows power on spikes, out put off.

Current limit over my 15ohm resistor

Noise

Power on directly to current limit.

[arvidb]

How are you feeling about your supply, now one year later?

How's the acoustic noise - is the fan loud when the supply is idle or not working hard?

Do you know if there's any energy in those power-on spikes - are they still there with a load attached (say 10 kΩ)?

[RogerThat]

Hi,

I haven't tested the energy in the spikes so can't say, but been having no problem with that. Sound is quite loud I would say, I turn it off when not in use. Fan speeds up under load....it is not regulated by temperature but by the power output...as soon as power goes up, the fan increases.

Only real complaints I have is with the remote control. I've been in contact with their service dep but haven't been able to get it to work(it some issue with the windows software).

When I don't need the higher voltage/current I always use my HP 3610A since it is silent...