Battery Source

Jim Vincent wrote:
wrote in message
oups.com...
That is just pure nonsense (the up vs down part). You can buy a 30W
(15V @ 2A) dc-dc converter for $62 from Mouser (search for
UHE-15/2000-Q12). The description says the input is 24V, but it really
is 9-36V, which should cover just about any battery you want to come up
with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
lower power ones even cheaper. If that makes your 14V heart feel
better, go for it (it won't damage your radio).

Tom Seim
2G DG-400


Get one of these for $45 and it will take your 12 V input and upconvert it
to 14V, handle 2A and be about 83% efficient.

http://www.dimensionengineering.com/AnyVolt.htm

I wish I had been available two years ago when I built my own 13.9V
upconverter.

This looks like a hobbyist product that would have to put into an
enclosure before using in a glider. What I found is a commercial dc-dc
converter that is in volume production from a company that has an
established reputation. It is also a much smaller package, has
over-voltage protection & short circuit protection, and meets all
specifications at -40 C. I doubt that the other unit has even been
tested at anything but room temperature. The level of testing and
quality assurance that a company like Datel has to offer should not be
underestimated.

Tom Seim
2G DG-400

Paul Remde wrote:

Hi,

It is my belief that all the work required to make an "upconverter" will
lead to only minimal increases in your radios transmit power (10 to 20%?).
It doesn't seem worth it to me. I vote 12V.

Even a 30% power output increase would yield only about 15% range
increase, so if one is otherwise happy with the radio's performance, I
agree. It might let you operate the radio for a longer time off the same
12 volt battery, if the radio isn't working satisfactorily below, say,
11.8 volts or so. If so, a $45-$60 converter would be a lot cheaper than
a new radio, easier and cheaper than trying to squeeze in a 2 volt cell
and buying a 14 volt charger to go with it, or fumbling with a handheld
when the panel radio quits.

As Dave K. suggests, noise from the switcher is a potential concern, but
I believe an external unit like the ones mentioned shouldn't be a
problem. We already have one or more switchers without problems in our
gliders to run the Ipaqs and transponders, and transceivers are well
shielded.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

"Eric Greenwell" wrote in message
...
Jim Vincent wrote:
wrote in message
oups.com...

That is just pure nonsense (the up vs down part). You can buy a 30W
(15V @ 2A) dc-dc converter for $62 from Mouser (search for
UHE-15/2000-Q12). The description says the input is 24V, but it really
is 9-36V, which should cover just about any battery you want to come up
with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
lower power ones even cheaper. If that makes your 14V heart feel
better, go for it (it won't damage your radio).

Tom Seim
2G DG-400



Get one of these for $45 and it will take your 12 V input and upconvert
it to 14V, handle 2A and be about 83% efficient.

http://www.dimensionengineering.com/AnyVolt.htm

I wish I had been available two years ago when I built my own 13.9V
upconverter.

Did you use it with your glider transceiver? How has it worked out, and do
you have any problems with noise in the receiver from the converter?


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Eric, I have not used the one I reference here. I have only used the one I
built. It has worked fine.I have not experienced any noise issues.

My premise for adding this to my ship is for the rare situation when the
battery is near death and I need to make an emergency transmission. I flip
one switch to make the GPS and Palm Pilot run off their own internal
batteries and flip another to activate the upconverter. BTW, I have a third
switch that selects either the main battery or a small backup battery
dedicated to the GPS secure data logger for badge purposes.

wrote in message
oups.com...

Jim Vincent wrote:
wrote in message
oups.com...
That is just pure nonsense (the up vs down part). You can buy a 30W
(15V @ 2A) dc-dc converter for $62 from Mouser (search for
UHE-15/2000-Q12). The description says the input is 24V, but it really
is 9-36V, which should cover just about any battery you want to come up
with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
lower power ones even cheaper. If that makes your 14V heart feel
better, go for it (it won't damage your radio).

Tom Seim
2G DG-400


Get one of these for $45 and it will take your 12 V input and upconvert
it
to 14V, handle 2A and be about 83% efficient.

http://www.dimensionengineering.com/AnyVolt.htm

I wish I had been available two years ago when I built my own 13.9V
upconverter.

This looks like a hobbyist product that would have to put into an
enclosure before using in a glider. What I found is a commercial dc-dc
converter that is in volume production from a company that has an
established reputation. It is also a much smaller package, has
over-voltage protection & short circuit protection, and meets all
specifications at -40 C. I doubt that the other unit has even been
tested at anything but room temperature. The level of testing and
quality assurance that a company like Datel has to offer should not be
underestimated.

Tom Seim
2G DG-400

Tom, my guess is the product is built with off the shelf components that are
more than adequate for our purposes. If I was to get one, I would pull the
display and Amp/Volt switch and mount them on my panel. The rest I would
put in a standard Radio Shack enclosure, drilled out for cooling/venting
purposes.

Regarding Datel, do you think they're in compliance with MILSPEC-1540B and
have been fully vibe/shock/thermal tested....I doubt it. Great that you
found another vendor, but please don't dis a vendor because they cater to
hobbyists. Dimension Engineering caters to radio control aircraft, which as
you surely know experience diverse environments. If their reliability was
bad, they'd be out of business in no time...s**t listed too on every
newsgroup. I'm sure either vendor would work just fine.

Paul Remde wrote:

Hi,

It is my belief that all the work required to make an "upconverter" will
lead to only minimal increases in your radios transmit power (10 to
20%?).
It doesn't seem worth it to me. I vote 12V.


I agree. 14V seems to be a magnificent solution to a non-existent
problem.

This summer I was sitting on an airport ramp after 8 hours in the air and
talking to glider pilots 200 miles away - on a single '12V' - 7.5 AH SLA
battery that was 2 years old. The battery still showed 12.5 V while
transmitting.

I do get the impression that newer SLA's perform better than those sold a
few years ago. It's pretty clear that newer radios work much better on
lower voltages. Taken together, it's hard to see what improvements are
needed.

If I ever see the need for more power, I'll replace it with a 12 AH version
and not fool with two batteries and an 'A-B" switch. I'll replace the 7.5AH
before next season even if it seems to be working fine.

My regimen is to make sure the battery goes on a very good charger right
after each use where it remains under trickle charge until I need it again.
I never leave a battery partially charged.


Bill Daniels

If the battery is near death will it provide the current required by
the upconverter? It's not magic and you can't get more power out of
the upconverter than you put in. I'm curious to know if you have
measured the performance with a "battery near death"?

An upconverter can't solve the available capacity problem. It can only
make it worse. (About 15 percent worse for the referenced converters).
They seem to be of no value except for powering equipment that will not
operate properly unless the available voltage is increased.

My prefered solution for emergencies is to have a handheld tranceiver
with an alkaline battery pack.

"Andy" wrote in message
oups.com...
If the battery is near death will it provide the current required by
the upconverter? It's not magic and you can't get more power out of
the upconverter than you put in. I'm curious to know if you have
measured the performance with a "battery near death"?

An upconverter can't solve the available capacity problem. It can only
make it worse. (About 15 percent worse for the referenced converters).
They seem to be of no value except for powering equipment that will not
operate properly unless the available voltage is increased.

My prefered solution for emergencies is to have a handheld tranceiver
with an alkaline battery pack.

Haven't tested near death, but actually was part of the thinking. If the
battery is near death, it has a little juice left. If the radio would not
tolerate a low voltage, then I could upconvert. Other part was optimizing
the power demands of the Dittle FSG-50 radio and Cambridge vario. Found no
real difference in performance between 12V and 13.9.
And yes, I do recognize the power losses.

I do this stuff for a living, and have over 30 years experience. In
that time I have developed methods and instincts for evaluating vendors
(after you are burned a few times you get to be really careful). First,
I have been using Datel products for 30+ years and have a real comfort
zone with them. Second, I read the data sheet (which you can also do).
Except that you can't do that with Dimension Engineering because there
isn't one! Now, that is a major red flag in my book (maybe not yours).
And don't assume that just because somebody is selling something that
it works as advertised. That is, perhaps, the silliest thing you said.

If you want a MIL SPEC qualified dc-dc, they are available too. Try
Vicor. You'll just pay A LOT more. The Datel unit is known as COTS (for
commercial off the shelf).

I said that it looks like a hobbyist product, and it does. Since when
is that *DISSING* anybody? Furthermore, what I was saying was that it
was MADE by hobbyists. That are lots of well designed commercial
products FOR hobbyists, but that is not the situation here.

I stand by my original comments and would recommend for the Datel unit
and strongly against the Dimension Engineering. You, of course, are
entitled to your own opinion.

Tom Seim
2G DG-400

wrote in message
ups.com...
I do this stuff for a living, and have over 30 years experience. In
that time I have developed methods and instincts for evaluating vendors
(after you are burned a few times you get to be really careful). First,
I have been using Datel products for 30+ years and have a real comfort
zone with them. Second, I read the data sheet (which you can also do).
Except that you can't do that with Dimension Engineering because there
isn't one! Now, that is a major red flag in my book (maybe not yours).
And don't assume that just because somebody is selling something that
it works as advertised. That is, perhaps, the silliest thing you said.

If you want a MIL SPEC qualified dc-dc, they are available too. Try
Vicor. You'll just pay A LOT more. The Datel unit is known as COTS (for
commercial off the shelf).

I said that it looks like a hobbyist product, and it does. Since when
is that *DISSING* anybody? Furthermore, what I was saying was that it
was MADE by hobbyists. That are lots of well designed commercial
products FOR hobbyists, but that is not the situation here.

I stand by my original comments and would recommend for the Datel unit
and strongly against the Dimension Engineering. You, of course, are
entitled to your own opinion.

Tom Seim
2G DG-400


I'll be sure to keep this in mind the next time I buy a radio control system
from Futaba or JR or any of the other well known vendors in radio control
space that provide receivers, motors, batteries and other flight critical
devices used in radio control aircraft. In my thirty years of radio control
aircraft, I can think of very few, if any, devices that have not worked as
promised. Oh yeah, very few of them have data sheets.

At what point does a company mature from a start up to what you consider a
bonafide COTS? Oh, just because a product was made by hobbyists, it is not
as legit as one made for hobbyists? Your critical thinking skills sure are
sharp...note the sarcasm here, Tom.

I am glad your instincts and methods were so correct in determining DE's
reliability and suitability. I guess I just have to rely on my ten silly
years of testing, system engineering and integrating aerospace critical
rocket gear and thirty years of fooling around with silly radio control toys
as my baseline in evaluation skills. I also rely on the Internet community
as an excellent near realtime feedback mechanism on radio control products;
if a product does not work as promised, the company gets slammed.

In the context of how you used the tem "hobbyist," I am very comfortable
saying you were dising it. Taking your comment that this is the "silliest
thing" I've said, you're implying that the other things I've said were silly
as well, just not as silly. Well, thanks for your succinct evaluation and
critique. I now know that if I need the final authority on what is valid
and what is not, I'll just go to you.

My, my. Are we getting a little testy here?

Actually, if you to Futaba's website you will find extensive data
sheets on their products. Futaba is, clearly, not garage shop opertion.


If you want to put something in your glider built by a garage shop
hobbyist, go right ahead. I will continue to be critical and not
recommend that course of action. I, too, am entitled to MY opinion.

Tom