"A Guide to Transponders in Sailplanes" - updated!

Excellent update on your fine article, thanks Eric!
Have to disagree regarding your points on NiMH batteries, though.
I've now flown now for over 2 years with them (including a dedicated
transponder battery) and I love them. Weight is about 60% of sealed
lead-acid, same for volume. The big advantage I see is in being able
to quick-charge them with 2A in a couple of hours very safely with
cheap automatic chargers available for example from all-battery.com or
ebay. I fly with 2 batteries for instrumentation/radio, each 5AH and
one for the transponder that has 10AH. One of the smaller batteries
is in the tail. Having much less mass in the area behind the
headrest is another plus. Shop around and find that the prices are
affordable and pre-wired 12V packs are offered.
I have not found the higher discharge rate in storage to be a factor.

Herb, J7

Herb wrote:
Excellent update on your fine article, thanks Eric!
Have to disagree regarding your points on NiMH batteries, though.
I've now flown now for over 2 years with them (including a dedicated
transponder battery) and I love them. Weight is about 60% of sealed
lead-acid, same for volume. The big advantage I see is in being able
to quick-charge them with 2A in a couple of hours very safely with
cheap automatic chargers available for example from all-battery.com or
ebay. I fly with 2 batteries for instrumentation/radio, each 5AH and
one for the transponder that has 10AH. One of the smaller batteries
is in the tail. Having much less mass in the area behind the
headrest is another plus. Shop around and find that the prices are
affordable and pre-wired 12V packs are offered.

Your Googling was more productive than mine! Please send links to the
batteries and chargers you use, and part numbers if you can. I'll review
them and rewrite that section as needed.

I have not found the higher discharge rate in storage to be a factor.

And pilots who find it is a factor might be able to counter it with
solar panel on the trailer.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

On Feb 20, 9:35 pm, Eric Greenwell wrote:
Herb wrote:
Excellent update on your fine article, thanks Eric!
Have to disagree regarding your points on NiMH batteries, though.
I've now flown now for over 2 years with them (including a dedicated
transponder battery) and I love them. Weight is about 60% of sealed
lead-acid, same for volume. The big advantage I see is in being able
to quick-charge them with 2A in a couple of hours very safely with
cheap automatic chargers available for example from all-battery.com or
ebay. I fly with 2 batteries for instrumentation/radio, each 5AH and
one for the transponder that has 10AH. One of the smaller batteries
is in the tail. Having much less mass in the area behind the
headrest is another plus. Shop around and find that the prices are
affordable and pre-wired 12V packs are offered.

Your Googling was more productive than mine! Please send links to the
batteries and chargers you use, and part numbers if you can. I'll review
them and rewrite that section as needed.

I have not found the higher discharge rate in storage to be a factor.

And pilots who find it is a factor might be able to counter it with
solar panel on the trailer.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes"http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" atwww.motorglider.org

Eric,
Here is a link for the battery (10Ah):
http://www.all-battery.com/index.asp...OD&ProdID=1344
The charger I use is on the same page.
I just ordered 10 individual NiMh batteries of 10Ah capacity on ebay
but will have to wire the pack up myself. The price was only $60 plus
$10 for shipping:
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN:IT&ih=014

Regards,
Herb