KX155 KX 155A Anybody know the difference?

Excellent point, I didn't but it is new.

Mike
MU-2

"Ben Jackson" wrote in message
news:fHtZc.16956$_g7.9700@attbi_s52...
In article ,
Mike Rapoport wrote:
It worked normally until one day when it totally failed, no display, no
radio, nothing. It could be outside the radio but I can't think of
anything
that coincides with the failure. It is a 14V airplane with a 28V 155.

Did you test the voltage converter?

--
Ben Jackson

http://www.ben.com/

I learned today that they do not make the KX-155A for 14 volt planes.
My installer said they could just pout a filter on the KX-155 radio to
prevent the interference with GPS. Does that make sense?

I am about to purchase a used KX-155/KI-209 Combo and have it installed.
I have a Garmin 430, so I want to make sure I am not going to run into
problems with my GPS.

-Sami
N2057M, Piper Turbo Arrow III

kage wrote:

THE major difference between the KX-155/165 and KX-155A/165A is this:

http://www.faa.gov/certification/air...st/8400-11.doc

3. Harmonic interference (12th and 13th harmonic) from VHF
transmissions on 121.150, 121.175, 121.200, 131.250, 131.275, and 131.300
MHz has been observed to adversely affect reception of the GPS signal. Low
pass or notch filters (with an insertion loss of 2 Db or less or the
aircraft VHF COM radio must be re-certified) installed at the output of the
VHF transmitter to attenuate the undesired harmonic signal, or modification
of the VHF transmitter to improve internal harmonic attenuation, may be
required. Shorted stubs, of appropriate lengths, could also possibly
provide effective filtering and antenna matching."



The straight 155/165 was designed long before GPS was ever envisioned, and
are very noisy in 12th and 13th harmonics. Most IFR installations with these
radios were made without regard to the interference, with the certifying
pilot either ignorant or lying about the interference.



The "A" model was designed to be free of these interferences.



Other nice features are much better feeling rotary switches, with smoother,
shorter and more precise clicks. Also, the 165A is available with 8.33 MHz
spacing. The US may or may not go to 8.33 spacing, but since Europe already
has the US will probably tow the line, like they did with METARS/TAF. Which
brings up a funny point. I fly all over Europe regularly. IT is very
uncommon to see a proper METAR/TAF report sequence. They report as they damn
well please with any sequence that comes to mind at the moment. To get a
proper sequence you need to fly in the US.



So much for the vaulted "commonality" that was forced down our throats!



Karl





"Mike Rapoport" wrote in message
ink.net...

The KX155 in my "new" airplane (Helio Courier) seems to have bitten the
dust. It looks like an old POS and I am trying to figure out what to do.
What are the functional differences between the KX155, KX165 and the
KX155A
and KX165A? The airplane has a Garmin 300XL as #1 and a switching relay
to
allow the 300XL or the KX155 to drive the HSI. I am trying to decide what
to do.

My options a

A:
#1 Garmin 430
#2 KX155
Get rid of the "GPS/NAV" switch/annunciator box

B:
Same as A but with 530. Pricey, but I could just buy the tray and
connectors and shuttle the 530 in my MU-2 back and forth until Garmin has
WAAS and then buy a 530A for the MU-2. This has the advantage of
presumably
saving the cost of the WAAS upgrade thereby reducing the 530 premium
somewhat.

C:
#1 Currently installed 300XL.
#2 KX 155 or 165 I would prefer the 165 since I can get rid of the
converter
box that drives the HSI.
Keep the GPS/NAV switch/annunciator box

The advantage of going with a 430 or 530 is that I have flown them for
800+
hrs and am comfortable with the operating logic. I can't say the same
about
the 300X:L.

Cost is an issue. This is a second airplane and I anticipate using it 95%
VFR. I would rather spend the money on floats or skis :-). Since the
airplane may be left unattended in the backcountry for days at a time, I
would also like avionics that are not very attractive to a thief.

What do you think?

Mike
MU-2

O. Sami Saydjari wrote:
I learned today that they do not make the KX-155A for 14 volt planes. My
installer said they could just pout a filter on the KX-155 radio to
prevent the interference with GPS. Does that make sense?

I am about to purchase a used KX-155/KI-209 Combo and have it installed.
I have a Garmin 430, so I want to make sure I am not going to run into
problems with my GPS.

Hi Sami,

I must have missed the posting to which you are replying, so I don't have the
context. I can say, however, that the KX-155 in my airplane certainly does
interfere with my handheld Garmin 196. Tuning the NAV side to either the FAY or
GSO VOR means a "lost satellite reception" message on the GPS. Perhaps a
certified GPS is less susceptible to interference.

If you installed radio first and then the GPS, the GPS would be tested for
interference during the installation, or at least that's how it used to be, I
think they've relaxed some of the installation requirements. It might be
worthwhile to ask the shop to do the interference test as if they were
installing the GPS.

Dave

Dave Butler writes:


I must have missed the posting to which you are replying, so I don't
have the context. I can say, however, that the KX-155 in my airplane
certainly does interfere with my handheld Garmin 196. Tuning the NAV
side to either the FAY or GSO VOR means a "lost satellite reception"
message on the GPS. Perhaps a certified GPS is less susceptible to
interference.

What frequencies do those VOR's have? I don't recognize them (I'm in
central California).

I'd like to repeat that test in my plane, I have a GNS430 and a portable
GPS196 that I carry as a backup.

-jav

Javier Henderson wrote:
Dave Butler writes:



I must have missed the posting to which you are replying, so I don't
have the context. I can say, however, that the KX-155 in my airplane
certainly does interfere with my handheld Garmin 196. Tuning the NAV
side to either the FAY or GSO VOR means a "lost satellite reception"
message on the GPS. Perhaps a certified GPS is less susceptible to
interference.


What frequencies do those VOR's have? I don't recognize them (I'm in
central California).

I'd like to repeat that test in my plane, I have a GNS430 and a portable
GPS196 that I carry as a backup.

Sorry, Jav, it annoys me when postings contain identifiers without any hint of
where they are, and now I'm guilty. Won't happen again.

FAY is Fayetteville, NC 180.80
GSO is Greensboro, NC 116.20

Dave

FAY is Fayetteville, NC 180.80
^^^^^^
108.80

Dave Butler wrote:
O. Sami Saydjari wrote:
I am about to purchase a used KX-155/KI-209 Combo and have it installed.
I have a Garmin 430, so I want to make sure I am not going to run into
problems with my GPS.

Hi Sami,

I must have missed the posting to which you are replying, so I don't
have the context. I can say, however, that the KX-155 in my airplane
certainly does interfere with my handheld Garmin 196. Tuning the NAV
side to either the FAY or GSO VOR means a "lost satellite reception"
message on the GPS. Perhaps a certified GPS is less susceptible to
interference.

I've got a KX-155, a Garmin 430 and a Garmin 195 (with external antenna)
on my plane. I've never noticed the problem you mention, Dave. Now it
could be that I never happened to tune my 155 to the frequencies you
mentioned. Since getting the 430, I rarely tune the 155 NAV to ANYTHING
;-). I also can't say that the 195 hasn't been affected as I don't tend
to kept a constant eye on it.


--
Frank Stutzman
Bonanza N494B "Hula Girl"
Hood River, OR

Another data point. I have had KX-155s working next to GPSs in several
different configurations for years with no problems. Currently a 530 and a
single 155 with GS.

"Frank Stutzman" wrote in message
...
Dave Butler wrote:
O. Sami Saydjari wrote:
I am about to purchase a used KX-155/KI-209 Combo and have it
installed.
I have a Garmin 430, so I want to make sure I am not going to run into
problems with my GPS.

Hi Sami,

I must have missed the posting to which you are replying, so I don't
have the context. I can say, however, that the KX-155 in my airplane
certainly does interfere with my handheld Garmin 196. Tuning the NAV
side to either the FAY or GSO VOR means a "lost satellite reception"
message on the GPS. Perhaps a certified GPS is less susceptible to
interference.

I've got a KX-155, a Garmin 430 and a Garmin 195 (with external antenna)
on my plane. I've never noticed the problem you mention, Dave. Now it
could be that I never happened to tune my 155 to the frequencies you
mentioned. Since getting the 430, I rarely tune the 155 NAV to ANYTHING
;-). I also can't say that the 195 hasn't been affected as I don't tend
to kept a constant eye on it.


--
Frank Stutzman
Bonanza N494B "Hula Girl"
Hood River, OR

That might be true.

But your installation will NEVER pass the required IFR certification tests
required buy the FAA.

Karl


"Dan Thompson" wrote in message
m...
Another data point. I have had KX-155s working next to GPSs in several
different configurations for years with no problems. Currently a 530 and a
single 155 with GS.

"Frank Stutzman" wrote in message
...
Dave Butler wrote:
O. Sami Saydjari wrote:
I am about to purchase a used KX-155/KI-209 Combo and have it
installed.
I have a Garmin 430, so I want to make sure I am not going to run
into
problems with my GPS.

Hi Sami,

I must have missed the posting to which you are replying, so I don't
have the context. I can say, however, that the KX-155 in my airplane
certainly does interfere with my handheld Garmin 196. Tuning the NAV
side to either the FAY or GSO VOR means a "lost satellite reception"
message on the GPS. Perhaps a certified GPS is less susceptible to
interference.

I've got a KX-155, a Garmin 430 and a Garmin 195 (with external antenna)
on my plane. I've never noticed the problem you mention, Dave. Now it
could be that I never happened to tune my 155 to the frequencies you
mentioned. Since getting the 430, I rarely tune the 155 NAV to ANYTHING
;-). I also can't say that the 195 hasn't been affected as I don't tend
to kept a constant eye on it.


--
Frank Stutzman
Bonanza N494B "Hula Girl"
Hood River, OR

kage wrote:
: That might be true.

: But your installation will NEVER pass the required IFR certification tests
: required buy the FAA.

: Karl

I have a pair of KX155 (not kx155a) and a Northstar M3. It passed the
interference tests as required by the FAA. I will check and see if any notch
filters were installed, but I do not believe there are any.

--
Aaron Coolidge