> However, by putting a very large capacitor AT THE AMPLIFIER, you can
> use smaller wires and a smaller power supply. The capacitor charges
> during periods of low current draw and then supplies power when
> needed.
This only works with CW and unprocessed SSB. Heavily processed SSB
and digital modes have a sufficiently high duty cycle (low peak to
average ratio) that the capacitor is not able to completely charge.
This effect is seen with transceivers using the Gamma Research HPS-1A:
http://www.gammaresearch.net/hps-1a.html. Better a properly sized
switching supply ... for example, the MFJ-4125 is about $80 on-line
for a 22A continuous/25A peak rating vs. $170 for the HPS-1A with its
5A continuous/22A peak rating.
73,
... Joe, W4TV
On 8/9/2010 11:11 AM, Vic K2VCO wrote:
> The capacitors don't replace batteries, but they can save a lot in
> power supply and cable size. I used to have a ss amp which required
> around 90A at 12v, and I used a pair of 75 amp Astrons and some huge
> 00 gauge welding cables to keep the drop down (connecting them to the
> amp was interesting).
>
> However, by putting a very large capacitor AT THE AMPLIFIER, you can
> use smaller wires and a smaller power supply. The capacitor charges
> during periods of low current draw and then supplies power when
> needed. These are popular here with the morons that have insanely
> powerful audio amplifiers in their trucks.
>
> On 8/9/2010 2:59 AM, Mike Tubby wrote:
>
>> I agree. With decent AGM batteries I can't really see the need
>> for capacitors.
>>
>> I have worked with AGM SLA betteries for many years in Ambulance
>> electrical systems. I also use them to power various repeaters and
>> have a split charge system in my SUV for powering ham radio
>> equipment.
>>
>> The trick to getting good performance and good outcomes is all to
>> do with how you treat your batteries (charge/discharge).
>>
>> Most SLA AGM batteries can be used with stepped charging with the
>> harder charging at 14.4V and float/maintained charging at 13.8V.
>> Most SLA batteries shouldn't be discharged below 10.8V as this may
>> permanently damage the chemistry - consider a low voltage
>> disconnector.
>>
>> There's some good information over at Battery university:
>>
>> http://www.batteryuniversity.com/>
>>
>> Regards
>>
>> Mike G8TIC
>>
>>>>
>>>> Has anyone ever built a power supply system with a capacitor??
>>>> what suggestions for doing it right? any url for a source on
>>>> such an installation? Anything else need to be added like a low
>>>> voltage cutoff, isolator, etc?
>>>>
>>>> thanks in advance
>>>>
>>>> chas k5dam
>
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