[hpsdr] Demeter = HPSDR power supply(?)

[Jeroen Bastemeijer]

Dear Michael,

Thanks for your reply. A switcher might be a solution... allthough, a 
non-switching supply will cause less spurs/birdies....

One thing, if it will be a switched mode power supply, the switching 
frequency should be tunable, this provides the means to get any spurs 
outside the band of reception. Some commercial HAM-power supplies have 
this feature.

The 24 volt for the OCXO is based on the HP oscillators (e.g. the 10811) 
which show up frequently on the surplus-market. But the +15Volts should 
be available as well.

I printed both references to read during the weekend. Have a nice weekend,

73 Jeroen PE1RGE

michael taylor wrote:

> On 6/8/07, Jeroen Bastemeijer <J.Bastemeijer at tudelft.nl> wrote:
>
>> First thing the power supply needs is a name. So I have been looking
>> into the Greek gods and other creatures, and I found.....
>>
>> "DEMETER"
>>
>> "Demeter" is the Goddes of  grain and fertility , the pure nourisher of
>
>
> Sounds good.
>
>
>> What I was thinking about:
>> * Output voltages +12 Volt, +5 Volt, -12 Volt (current ratings to be
>> detrmined)
>
>
> Obviously current ratings are an important factor.
>
>> * An optional standby power supply for the OCXO (24 Volt?) and the
>
>
> I'm not sure if there has been any decision on the OCXO choice, but
> the ones mentioned on the Gibraltar web page are 5Vdc and 15Vdc.
>
>> * Input voltage: 13,8 Volt (mobile use), 110 Volt, 230 Volt
>
>
> This suggests (to me) consideration of using a switching regulator
> design for the AC mains (~90-240V AC designs are reasonable common)
> to 13.8Vdc, with a LDO linear regulator design with HF attenuation for
> the final outputs.
>
> Linear Tech AN-101
> <http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1042,C1034,D11877> 
>
> EDN article by Jim Williams
> <http://www.edn.com/article/CA6288040.html>
>
> Is limiting ripples and spikes to less than 200uV good enough for us 
> or not?
>
>> * Computer monitoring of the currents and voltages
>
>
> And case ambient temperature? Possibly useful for remote site or
> unattended (beacon monitoring) usage. USB connection?
>
> -Michael, VE3TIX
>
>
>

-- 
Ing. Jeroen Bastemeijer

Delft University of Technology
Department of Electrical Engineering
Electronic Instrumentation Laboratory
Mekelweg 4, Room 13.090
2628 CD Delft
The Netherlands

Phone: +31.15.27.86542
Fax: +31.15.27.85755
E-mail: J.Bastemeijer at TUDelft.nl
GPS: Lat N52.00002 Lon E4.37157 Alt 46.2m


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