[time-nuts] potential low-RFI power supply

[jimlux]

On 5/18/20 10:19 AM, Joseph Gwinn wrote:
> On Mon, 18 May 2020 12:00:02 -0400, time-nuts-request at lists.febo.com
> wrote:
> Re: time-nuts Digest, Vol 190, Issue 30
> 
>> Message: 1
>> Date: Sun, 17 May 2020 12:53:42 -0600
>> From: Eric Scace <eric at scace.org>
>> To: Time Nuts email list <time-nuts at lists.febo.com>
>> Subject: [time-nuts] potential low-RFI power supply
>> Message-ID: <C1DDF9AF-78D7-4DF1-876B-4FAE5F398D65 at scace.org>
>> Content-Type: text/plain;	charset=utf-8
>>
>> Pro Audio Engineering announced a sale (through Friday) on its
>> nominal 14 Vdc 4A switching supply
>> <https://proaudioeng.com/products/pae-kx33-low-rfi-ac-power-supply/>.
>> The test results
>> <https://proaudioeng.com/products/pae-kx33-low-rfi-ac-power-supply/>
>> webpage compares noise on the DC output and noise frequency spectrum
>> under a variety of conditions with a lead-acid battery, an Astron
>> linear supply, and a variety of switching supplies from other
>> manufacturers.
>>
>> I have not used this and can?t vouch for its performance. Given
>> recent discussions here on supplies, the analysis might be
>> interesting. At least the supplier has attempted to quantify the
>> performance of its power supply and make that information available
>> to the prospective purchaser.
>>
>> It would be interesting to see comparable (or more suitable)
>> measurements made by others posted here.
> 
> Given that this power supply is intended for audio applications such as
> mixer boards, if the switching frequency exceeds say 200 KHz, none of
> the ripple spurs will matter, as they are far above the band.  Hmm.
> Unless that get too close to the sampling rate of some delta-sigma
> converter I suppose.

Actually, it's intended as a power supply for HF transceivers, so noise 
in the HF band is of interest. Especially if it's radiated from the 
power cable.