radio interference with transmission/reception with Solo 2625-01running

[November Bravo]

I own a Ventus 2CXM built 2007 with a factory installed Walter Dittle
FSG 2T radio. I use the Sennheiser headphones (factory installation)
during the engine running procedures. Unfortunately, I have always
had severe interference with the radio tramsmission/reception during
the engine run. During the engine run, whether idle or full power,
the reception is weak and garbled with a great deal of backround white
noise. My transmissions are totally garbled, weak, and
uninterpretable even to other aircraft 50 yards away. When the engine
is not running I have not problems and my fellow pilots report that my
transmissions are strong and clear. This is becoming a safety problem
while taxing onto the active runway, as our glider airport is now very
busy with power traffic and a new flight school. Has anyone
encountered this problem and know of a list of things to check before
sending the aircraft to an aviation radio specialist?

John Iacobucci
Grand Rapids, Michigan USA
+1 (616) 485-3980

[Vaughn Simon]

"November Bravo" > wrote in message
...
>Has anyone
> encountered this problem and know of a list of things to check before
> sending the aircraft to an aviation radio specialist?
>

Off the top of my head, you are probably receiving interference via the power
system or your engine is radiating interference that being picked up by the
antenna and drowning out reception.

The first problem might be solved with some filtering and careful attention to
your aircraft's ground system, and the second problem might respond to an
antenna relocation and/or engine electrical shielding. Make sure that the
antenna coaxial cable is not accidentally serving as the power ground for the
radio (unplug antenna and make sure that radio still has power)

Two things you can easily check that would provide important troubleshooting
clues:

1) If you use a portable radio inside the cockpit with the engine running, do
you have the same problem? and...
2) If you power the Dittle from a temporary battery (not connected to the
glider's electrical system) does it make any difference in the transmission
and/or reception?

Vaughn

[Eric Greenwell]

November Bravo wrote:
> I own a Ventus 2CXM built 2007 with a factory installed Walter Dittle
> FSG 2T radio. I use the Sennheiser headphones (factory installation)
> during the engine running procedures. Unfortunately, I have always
> had severe interference with the radio tramsmission/reception during
> the engine run. During the engine run, whether idle or full power,
> the reception is weak and garbled with a great deal of backround white
> noise. My transmissions are totally garbled, weak, and
> uninterpretable even to other aircraft 50 yards away. When the engine
> is not running I have not problems and my fellow pilots report that my
> transmissions are strong and clear. This is becoming a safety problem
> while taxing onto the active runway, as our glider airport is now very
> busy with power traffic and a new flight school. Has anyone
> encountered this problem and know of a list of things to check before
> sending the aircraft to an aviation radio specialist?

Have you tried one of the owners groups? Other people with Solo engine
self-launchers have had problems like yours. From the ASA website
(motorglider.org) "Links and Newsgroups":

http://groups.yahoo.com/group/DGSoloUsersGroup/

http://groups.yahoo.com/group/Ventus_2CM/

--
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