|
|
OK Bill, that adds up with yesterday's tests that I ran.
With the Icom radio about 18" from the test bench EM2 I found no
noise (that is how I tested in the past). I started moving the antenna
closer & closer until I was able to pick up hash (white) noise when
several inches away. Thought there might be a problem but then I found
that I could get as much or more noise when I brought the antenna close to
ANY of the computerized equipment in the room (digital O-scope, freq.
counter, PC, monitor, intrusion alarm system, etc. At this
point I think it is a matter of proper cable routing.
Tracy
----- Original Message -----
Sent: Wednesday, June 28, 2006 6:18
PM
Subject: [FlyRotary] Re: Radio
noise
It appears to be the fix, i.e. repositioning the wires.
My stack, working from the bottom up is Transponder, SL-40, SL-30, PMA-6000
audio panel, and EM-2. The harness from the EM-2 was going across the
top of the audio panel, and raising the wires about an inch or so seems to
have eliminated the problem.
Bill Schertz
KIS Cruiser # 4045
----- Original Message -----
Sent: Wednesday, June 28, 2006 4:02
PM
Subject: [FlyRotary] Re: Radio
noise
Hi Bill, will be very interested in your results. Have had a
couple of other builders mention noise but I have not had any radio noise in
my installation and a hand held turned up none (here) on the problem
units from field. If the wire positioning can make that much
difference , that might explain it. I'll do some more testing here to
see if I can nail this down. Might have something to do with
un-terminated inputs as well since my test bench setup has all inputs
wired.
Tracy
----- Original Message -----
Sent: Saturday, June 24, 2006 6:58
PM
Subject: [FlyRotary] Re: Radio
noise
After hooking up resistors or sensors to all outputs, I
still had the noise.
I then wired in a 100microfarad capacitor on the
inlet line between +12 and
GND, and no noticable
effect.
Further mucking around found that repositioning the wires
coming out of the
back of the EM-2 by about 1/2 inch eliminated the
noise! Will see if this
'solution' holds up with further tests on
Monday.
Thanks for all the suggestions.
Bill Schertz
KIS
Cruiser # 4045
----- Original Message -----
From: "Bill Schertz"
<wschertz@comcast.net>
To:
"Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent:
Friday, June 23, 2006 11:12 PM
Subject: [FlyRotary] Re: Radio
noise
> Ed, that is a worthwhile suggestion. I am going to
pick up some resistors
> tomorrow. I note that the sensors are 10
to 180 ohms for temp and
> pressure, was there a reason for the
suggestion of 20K?
>
> Thanks.
> Bill Schertz
>
KIS Cruiser # 4045
> ----- Original Message -----
> From: "Ed
Anderson" <eanderson@carolina.rr.com>
>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
>
Sent: Friday, June 23, 2006 9:07 PM
> Subject: [FlyRotary] Re: Radio
noise
>
>
>> Just a WAG, Bill. Could it be the
oscillator of the microchip in the EM2
>> generating the nose
because some of the pins (tied to the sensors) are
>> not a
complete circuit. Might try just hooking up some 20K ohm resistors
>> between your sensor leads and ground just to see.
Either that or perhaps
>> getting feed back from the chip on
your power lines suggesting a low
>> value .01uf
capacitor.
>>
>> Ed
>> ----- Original Message
-----
>> From: "Bill Schertz" <wschertz@comcast.net>
>>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
>>
Sent: Friday, June 23, 2006 6:42 PM
>> Subject: [FlyRotary] Radio
noise
>>
>>
>>>I am in the process of wiring
up and testing each piece of electronic
>>>equipment before
putting the top on my plane which will make it much
>>>harder
to get access.
>>>
>>> I have an SL-30 NAV/COM and
SL-40 COM. The COM works, but when I turn on
>>> the EM-2 I
get a bunch of hash (white noise). Any suggestions on
>>> diagonstics? The EM-2 is not connected to 'all' sensors
yet.
>>>
>>> Bill Schertz
>>> KIS
Cruiser # 4045
>>>
>>> --
>>>
Homepage: http://www.flyrotary.com/
>>>
Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
>>>
>>
>>
>>
>>
--
>> Homepage: http://www.flyrotary.com/
>>
Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
>
>
>
--
> Homepage: http://www.flyrotary.com/
>
Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
--
Homepage: http://www.flyrotary.com/
Archive
and UnSub: http://mail.lancaironline.net/lists/flyrotary/
|
|