I have a TGE battery booster going between my homebrew adjustable power
supply that feeds a pair of AGM batteries via a blocking diode setup. With
slip on ferrite beads on both the B+ input and output of the battery
booster, I cannot tell if the battery booster is running or not.
----- Original Message -----
From: "Dr. Gerald N. Johnson" <firstname.lastname@example.org>
Sent: Sunday, June 07, 2009 7:27 PM
Subject: Re: [TenTec] Help with gel cell battery and solarcharging
> On Sun, 2009-06-07 at 12:14 -1000, Ken Brown wrote:
>> Hi John,
>> I recommend Home Power Magazine. If you can find someone who
>> subscribes, who would let you borrow a bunch of issues, or a library
>> that has it, you can learn plenty about these kinds of systems. Even
>> without subscribing you can get a lot of information on their web site.
>> You can also get a package deal including past issues on CD if you
>> subscribe. There is lots and lots of information there.
>> If you intend to run your radio directly from the batteries, not
>> using an inverter and 120 VAC, then you probably want a 12 VDC battery
>> system. You would probably use 12 V photovoltaic panels. A MPPT (
>> maximum power point tracking) charge controller between the photovoltaic
>> panels and the battery will possibly be a source of RF noise, since they
>> are switched mode voltage converters that can get some charge current
>> into your batteries, even when the voltage coming out of the PV panels
>> is lower than the battery voltage. Since these charge controllers are
>> voltage conversion devices, your PV panels may not have to be a 12 volt
>> system to use a 12 volt battery. You can also use DC to DC voltage
>> conversion from the battery to the radio, another possible noise source,
>> but also another possible way to have higher current at the load with a
>> higher voltage lower current capacity battery.
>> By using a 12 volt battery system, you could operate the radio
>> directly off the battery, with no switched mode voltage conversions
>> running at night when the sun is down. A nominal 12 volt battery system
>> will drop below 12.6 volts output when there is still a lot of available
>> energy left in it. Low voltage cutouts to protect the battery from
>> excessive discharge are typically a bit under 12 volts for a nominally
>> 12 volt battery system. But will the Orion II still be working at that
>> voltage? You need to find out what DC voltage the Orion II really needs
>> to work properly. A six cell battery system may not actually provide
>> that voltage for very long. You may need a DC to DC converter between
>> the battery and the load anyway, in which case you may want to consider
>> a higher voltage battery. 24 volt and 48 volt systems are pretty common
>> these days. 12 volt systems getting less and less common anymore when
>> inverting to 120 VAC. By using higher voltage PV arrays and batteries,
>> you can use smaller wire. Twelve volt systems these days seem to be only
>> use for very small systems with only one or two PV panels in the array.
>> The simplest system for you would probably be one or more 12 Volt
>> PV panels, a charge controller and a 12 volt battery of the necessary
>> Ampere Hour capacity, which depends on your usage. You may also want
>> another way to charge the batteries when you get a lot of cloudy weather.
>> QST had an article about 12 VDC to 120 VAC inverters recently,
>> which was the best description of the difference between 'True sine
>> wave" inverters and modified square wave inverters (which the inverter
>> manufacturers marketing departments call "modified sine wave") I have
>> seen. The renewable energy folks at Home Power Magazine and other
>> information sources often only discuss that difference in terms of what
>> devices you can power, and not so much discussion about the generation
>> of RF noise.
>> If you have a safe place to keep your battery, which includes
>> venting and a way to contain any possible electrolyte spillage, then I
>> would go with a liquid electrolyte lead acid battery. Plain liquid
>> electrolyte batteries are a bit more tolerant to accidental abuse than
>> gel cells, and for the same capacity they are usually cheaper. If you
>> overcharge or charge at too high a rate you may evaporate some
>> electrolyte. With a liquid cell you can replace it by adding some
>> distilled water. With a sealed gel cell battery, if you vent any water
>> vapor from the gel electrolyte, it is gone forever, and the battery will
>> never be the same.
>> Ken N6KB
> There is a ham made product for getting 13.8 volts out of a 12 volt lead
> acid battery, surely its not noisy. Whether it would handle an Orion II
> at full transmit, I don't know.
> Fully wet cells are the most tolerant. Auto batteries are not very
> tolerant of deep loading without rapid charging. Deep cycle or marine
> batteries are more tolerant of long discharge times. When you pick out
> one in the big box store, learn the date coding and pick the one that
> has been on the shelf the shortest time. It will give you the best
> You need a charge regulator and one that makes up for low solar panel
> voltage gets considerably more energy per day.
> Energy from solar panels is horrendously expensive compared to paying
> the power company even 14 cents a KWH unless you have to pay several
> thousand bucks a mile for the power line.
> 73, Jerry, K0CQ
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