[hpsdr] LPU Capacity
n3evl
n3evl at townisp.com
Wed Dec 28 16:21:55 PST 2011
Thanks for the clarification on the meaning of the 5VSB.
As far as the picoPSU being a bit RF-noisy, can't say I've noticed any
difference since switching from the LPU, not that I've done any
scientific A-B tests.
73,
Pete, N3EVL
On 12/28/2011 6:08 PM, Scott Cowling wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> Hi Pete,
>
> The 5VSB pin is +5 Volt standby power, used to power things like the
> NIC (for wake on LAN) and the power on-off switching circuitry that
> has to be always active in the PC. It is not used (or even distributed
> over the Atlas bus) by any HPSDR boards.
>
> The picoPSU is a good choice, but it is a bit RF-noisy. The reason
> that it is so small and runs so cool is that it is a switch-mode power
> supply (SMPS) as opposed to the LPU, which is a linear power supply.
>
> The 5V regulator on the LPU is rated at 2A continuous, but the pico
> fuses are not. When you get up towards the maximum rating of the
> regulator, the fuses will trip (and reset, and trip, and...). This is
> the reason for the LPU errata suggesting that you remove them from the
> circuit (short them out).
>
> 73,
> Scotty WA2DFI
>
>
> At 14:04 2011-12-28 -0500, n3evl wrote:
>> ***** High Performance Software Defined Radio Discussion List *****
>>
>>
>> A couple of months ago I decided to retire LPU in favor of the
>> picoPSU-120-WI-25. This appears to fulfill the current requirements
>> of the usual suspects + Metis at 1 Gigabit. The picoPSU spec quotes
>> two figures for 5V:
>>
>> 5V 6A
>> 5VSB 1.5A
>>
>> I have no idea what 5VSB refers to - maybe somebody can shed some
>> light on this designation?
>>
>> The picoPSU unit is quite small and does not have the tall heatsinks
>> used with LPU. It supposedly runs quite a bit cooler but I left the
>> fan in place figuring some air flow through Pandora can't hurt.
>>
>> Pete, N3EVL
>>
>> On 12/28/2011 10:03 AM, Chris Day wrote:
>>>
>>> ***** High Performance Software Defined Radio Discussion List *****
>>>
>>>
>>>
>>> Thanks, Erich. Replacing the soft fuses with wire has been enough so
>>> far, but I haven't fired up the transmitter section of Pennylane
>>> yet. Linear chain will be external, so there will be no extra load
>>> from that. Meanwhile, playing with Mercury with delightful results.
>>>
>>> Chris Day
>>> AE6VK
>>>
>>>
>>> > Date: Wed, 28 Dec 2011 04:12:10 -0800
>>> > From: <mailto:vk5hse at yahoo.com>vk5hse at yahoo.com
>>> > To: <mailto:hpsdr at lists.openhpsdr.org>hpsdr at lists.openhpsdr.org
>>> > Subject: Re: [hpsdr] LPU Capacity
>>> >
>>> > ***** High Performance Software Defined Radio Discussion List *****
>>> >
>>> > Have cobbled together various reflector postings for my own
>>> reference as well as for others.
>>> >
>>> >
>>> > There was a summary posted to the reflector that is worth reviewing:
>>> >
>>> >
>>> <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2011-March/014678.html>http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2011-March/014678.html
>>> >
>>> > the meaty bits were:
>>> >
>>> > Magister = Ozy
>>> >
>>> >
>>> > power consumption summary:
>>> >
>>> >
>>> > 12 V 5 v
>>> > OZY .001 A .1 A
>>> > PENY .4 A .2 A
>>> > MERC .2 A .5 A
>>> >
>>> > Metis 100 .4A
>>> >
>>> > Metis 1000bT .75A
>>> >
>>> >
>>> > no-one seems to have stated excalibur power requirements, but it
>>> doesn't appear to be huge
>>> >
>>> >
>>> > add the LPU errata document:
>>> >
>>> >
>>> <http://www.tapr.org/pdf/LPU_Errata.pdf>http://www.tapr.org/pdf/LPU_Errata.pdf
>>> >
>>> > which mentions in errata #2:
>>> >
>>> > "Description of Error:
>>> > Fuses F2 and F3 are underrated for a full system. They are rated
>>> at continuous 1.1A without
>>> > tripping, while an Ozy/Mercury/Penelope system draws typically
>>> 1.3A from the +5V rail.
>>> >
>>> >
>>> > Symptoms:
>>> > An Ozy/Mercury/Penelope system will operate for a short period and
>>> then unexpectedly shut
>>> > down. The time can vary, but is typically around 10 minutes. This
>>> is due to F2 opening and shutting
>>> > down the +5V output. (Note that F2 doesn't actually "open"; it
>>> becomes higher resistance to protect
>>> > the load.) After a power cycle, normal operation resumes.
>>> >
>>> >
>>> > Recommended Corrective Action:
>>> > Short across F2 and F3 with pieces of wire."
>>> >
>>> >
>>> >
>>> > There has also been talk of strapping the 12V feedtrhough for high
>>> power things like a PA
>>> >
>>> >
>>> <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2010-July/012616.html>http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2010-July/012616.html
>>> >
>>> > and some suggestion of shorting the 5V fuse and relying on the
>>> regulator to protect itself +/- modifying R6 the series resistor
>>> >
>>> >
>>> <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2010-July/012617.html>http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2010-July/012617.html
>>> > _______________________________________________
>>> > HPSDR Discussion List
>>> > To post msg: <mailto:hpsdr at openhpsdr.org>hpsdr at openhpsdr.org
>>> > Subscription help:
>>> <http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org>http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
>>> > HPSDR web page: <http://openhpsdr.org>http://openhpsdr.org
>>> > Archives:
>>> <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/>http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>>>
>>>
>>>
>>> _______________________________________________
>>> HPSDR Discussion List
>>> To post msg: <mailto:hpsdr at openhpsdr.org>hpsdr at openhpsdr.org
>>> Subscription help:
>>> <http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org>http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
>>> HPSDR web page: <http://openhpsdr.org>http://openhpsdr.org
>>> Archives:
>>> <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/>http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>>>
>>> No virus found in this message.
>>> Checked by AVG - <http://www.avg.com>www.avg.com
>>> Version: 2012.0.1901 / Virus Database: 2109/4708 - Release Date:
>>> 12/28/11
>>
>> _______________________________________________
>> HPSDR Discussion List
>> To post msg: hpsdr at openhpsdr.org
>> Subscription help:
>> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
>> HPSDR web page: http://openhpsdr.org
>> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>
>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help:
> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.1901 / Virus Database: 2109/4709 - Release Date: 12/28/11
>
>
1325118115.0
More information about the Hpsdr
mailing list