Switching between multiple Volksloggers

Should work, best to test it first. Also, check to see if there is a
"ground" in the serial wiring diagram too. If so, you need to connect
them together as well, but that can be done permanently (not switched) I
would think.

Todd Pattist wrote:

A friend has two Volksloggers, primary and secondary. The
primary feeds data to his SN-10. The primary failed last
weekend and he wants a way to switch the secondary to the
SN-10 while in flight if it happens again.

I suggested a simple double pole double throw switch to
switch the TXD and RXD lines from the SN-10 between the
primary and secondary VL's. Has anyone done this? Any
problems?

Thanks.
Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

I do the same with my twin colibris. Just switch the tx and RX lines. No
Problem

Ian


"Todd Pattist" wrote in message
...
A friend has two Volksloggers, primary and secondary. The
primary feeds data to his SN-10. The primary failed last
weekend and he wants a way to switch the secondary to the
SN-10 while in flight if it happens again.

I suggested a simple double pole double throw switch to
switch the TXD and RXD lines from the SN-10 between the
primary and secondary VL's. Has anyone done this? Any
problems?

Thanks.
Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

Hi,

Several years ago a used a double pole-double throw switch to select between
my GPS-NAV and Garmin 90 for input to my L-NAV. That way I gained access to
the large Jepessen database when I was a long way from home. It worked
great.

However, the downside to using a switch is that RS-232 data lines are noisy
and it would be difficult to shield the switch well (putting foil around it
wont help). It may cause radio interference. Therefore, I don't really
recommend it.

Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com

"tango4" wrote in message
...
I do the same with my twin colibris. Just switch the tx and RX lines. No
Problem

Ian


"Todd Pattist" wrote in message
...
A friend has two Volksloggers, primary and secondary. The
primary feeds data to his SN-10. The primary failed last
weekend and he wants a way to switch the secondary to the
SN-10 while in flight if it happens again.

I suggested a simple double pole double throw switch to
switch the TXD and RXD lines from the SN-10 between the
primary and secondary VL's. Has anyone done this? Any
problems?

Thanks.
Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

A friend has two Volksloggers, primary and secondary. The
primary feeds data to his SN-10. The primary failed last
weekend and he wants a way to switch the secondary to the
SN-10 while in flight if it happens again.

Diving into this perhaps a little late, but I wonder the value of doing this.
Is the SN-10 that much more reliable than a Volkslogger, your battery, or the
wiring switches? If you're found any of these individual components to
repeatedly fail, then I advocate replacing the component.

Looking at just two of the devices that contribute to the FMEA (Failure Modes
and Effects Analysis), let's assume the SN-10 and Volkslogger are equally
reliable. By only having one redundant, you're reduced the chance of failure
in half. BUT, assuming both are very reliable, on the order of 10,000 between
hours (reasonable), you'll increase the reliability from 99.999998 % to
99.999999 %.

Lastly, the switch that you need to switch between the two Volksloggers has its
own reliablity issue. That in inself may make the whole darn thing less
reliable.

I think the KISS approach is the best...one of each gizmos.

Batteries are a different story though. I have a spare one purely to power the
datalogger if the main one dies.

Jim Vincent
N483SZ
illspam