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| | |-+  A simple test everyone with a remote can try - Remote Recording interference

Poll

Do you get interference when recording with the remote plugged in?

Yep
15 (88.2%)
Nope
2 (11.8%)

Total Members Voted: 17

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Author Topic: A simple test everyone with a remote can try - Remote Recording interference  (Read 18978 times)

Offline Mmmm

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A simple test everyone with a remote can try - Remote Recording interference
« on: June 01, 2006, 06:35:37 AM »
You can test this easily as long as you have a remote handy..

-Go into the recording screen (make sure input is set as line in and no microphone is attached)
-Make sure the remote is plugged in
-Turn gain up until you see a readout on the peakmeter (mine starts at about 26db on right channel)
-Turn it up a bit more so that you can see the readout clearly (about 35db is fine for mine)
-Now pull out the remote. Has the peakmeter gone blank?
-Plug remote back in. Interference?

If yes vote yep....

I'm curious as to whether this is just my unit or is it a universal problem or maybe it has something to do with the ticking phenomenon.

Maybe the ticking fix being active on the recording screen may fix this. Who knows....
« Last Edit: June 02, 2006, 06:29:07 AM by Mmmm »
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My H120 build with Recording Enhancements Pack
Some examples of recordings done on H140 with Rockbox

Offline Hansmaulwurf

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Re: Interference in recordings with remote?
« Reply #1 on: June 01, 2006, 07:56:54 AM »
Just tested it. I see a readout on the right channel, but only if gain is at 47dB or higher(you can only go up to 48dB). And it is a really thin line, only the first line of pixels. When I pull out the remote the readout is gone.

I have "Reduce Ticking" 'on'.
« Last Edit: June 01, 2006, 07:58:36 AM by Hansmaulwurf »
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Offline whatboutbob

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Re: Interference in recordings with remote?
« Reply #2 on: June 01, 2006, 09:02:18 AM »
crap crap crappety crap.

I just did some tests on this remote interference.  Can't believe I haven't noticed it before.  I just wrote the noise off to mic shortcomings...how wrong I was.

As Mmmm suggested, I set source to line in, didn't plug a mic in, then recorded w/ a varety of gain, then measured noise floor (in dB):

First with no gain (left channel, right channel):
           
w/ remote: -84, -81
w/o rem:    -84, -84

20dB gain:
w/ remote: -72, -63
w/o rem:    -81, -81

48dB gain:
w/ remote: -42, -36
w/o rem:    -52, -52

I repeat: crap crap crappety crap.

LinusN suggested that the main iriver units aren't grounded properly...some worse than others.  I think this idenitifies the damn source of cell phone interference I've encountered in some of my recordings.  Unless I'm mistaken (and that's entirely possible) the remote is essentially acting like a giant antenna.

So, now all we need is an electronics guru to confirm this issue and find a fix (please!). :)

edit: oh, and 'reduce ticking' makes no obvious impact on the interference.
« Last Edit: June 01, 2006, 09:05:35 AM by whatboutbob »
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Offline Mmmm

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Re: Interference in recordings with remote?
« Reply #3 on: June 01, 2006, 10:00:42 AM »
Quote from: Hansmaulwurf on June 01, 2006, 07:56:54 AM
Just tested it. I see a readout on the right channel, but only if gain is at 47dB or higher(you can only go up to 48dB). And it is a really thin line, only the first line of pixels. When I pull out the remote the readout is gone.
Hansmaulwurf it seems you have the interference but so slight as to be unnoticable...Do you usually have ticking when you listen to music with the fix off?


Quote from: whatboutbob on June 01, 2006, 09:02:18 AM
crap crap crappety crap.
Yep.... isn't it just?

Quote
First with no gain (left channel, right channel):
           
w/ remote: -84, -81
w/o rem:    -84, -84

20dB gain:
w/ remote: -72, -63
w/o rem:    -81, -81

48dB gain:
w/ remote: -42, -36
w/o rem:    -52, -52
Ahhh some solid data to chew on......

Yep...its crap!  :D
Quote
edit: oh, and 'reduce ticking' makes no obvious impact on the interference.
I don't think that the ticking fix is active during recording even if you have it set to on (could be totally wrong there though).
I thought maybe if it was active it may fix the problem...may be worth a try eh?
« Last Edit: June 01, 2006, 10:04:49 AM by Mmmm »
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My H120 build with Recording Enhancements Pack
Some examples of recordings done on H140 with Rockbox

Offline Hansmaulwurf

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Re: Interference in recordings with remote?
« Reply #4 on: June 01, 2006, 11:40:10 AM »
Quote from: Mmmm on June 01, 2006, 10:00:42 AM
Hansmaulwurf it seems you have the interference but so slight as to be unnoticable...Do you usually have ticking when you listen to music with the fix off?
I hear the ticking only when im at the WPS and music is stopped or Volume is set lower than -82dB. And even with that Volume you have to listen very carefully to hear it.

Ah, and its no difference if the "Reduce Ticking" is On or Off. the interfernece stays the same.
« Last Edit: June 01, 2006, 11:50:40 AM by Hansmaulwurf »
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Offline whatboutbob

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Re: Interference in recordings with remote?
« Reply #5 on: June 01, 2006, 09:35:41 PM »
Mmmm, have you confirmed that the cell interference only occurs with the remote attached?
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Offline Mmmm

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Re: Interference in recordings with remote?
« Reply #6 on: June 02, 2006, 03:37:16 AM »
Quote from: Hansmaulwurf on June 01, 2006, 11:40:10 AM
Quote from: Mmmm on June 01, 2006, 10:00:42 AM
Hansmaulwurf it seems you have the interference but so slight as to be unnoticable...Do you usually have ticking when you listen to music with the fix off?
I hear the ticking only when im at the WPS and music is stopped or Volume is set lower than -82dB. And even with that Volume you have to listen very carefully to hear it.

Ah, and its no difference if the "Reduce Ticking" is On or Off. the interfernece stays the same.

So you have very minor ticking and very minor interference too....this supports the theory eh?


Quote from: whatboutbob on June 01, 2006, 09:35:41 PM
Mmmm, have you confirmed that the cell interference only occurs with the remote attached?
I got the cell phone interference without the remote attached! (I don't use the remote anymore bacause of the interference!)
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My H120 build with Recording Enhancements Pack
Some examples of recordings done on H140 with Rockbox

Offline whatboutbob

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Re: Interference in recordings with remote?
« Reply #7 on: June 02, 2006, 04:57:46 AM »
Quote from: Mmmm on June 02, 2006, 03:37:16 AM
I got the cell phone interference without the remote attached! (I don't use the remote anymore bacause of the interference!)

bugger.
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Offline petur

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Re: Interference in recordings with remote?
« Reply #8 on: June 02, 2006, 06:13:12 AM »
Quote from: whatboutbob on June 02, 2006, 04:57:46 AM
Quote from: Mmmm on June 02, 2006, 03:37:16 AM
I got the cell phone interference without the remote attached! (I don't use the remote anymore bacause of the interference!)

bugger.

This doesn't surprise me at all. There's no shielding in the player and cell phone signals are strong enough. I even have a recording with interference on, the cell phone must have been 50cm away (concert with seats).

Damn cell phones!
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Offline whatboutbob

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #9 on: June 02, 2006, 06:18:46 AM »
peutr: that's what i'm talking about...interference actually getting onto the recordings...it happens on prolly half my recordings. 'tis really p!ssing me off.
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Offline Mmmm

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #10 on: June 02, 2006, 06:24:24 AM »
I suppose you could put it in a nice lead box when you want to record!  :D
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My H120 build with Recording Enhancements Pack
Some examples of recordings done on H140 with Rockbox

Offline whatboutbob

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #11 on: June 02, 2006, 06:52:31 AM »
see...you jest...but i've actually looked into these:

http://en.wikipedia.org/wiki/Faraday_cage
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Offline renho3k

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #12 on: June 02, 2006, 01:49:57 PM »
mine starts at about 28dB.
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Offline Mmmm

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #13 on: June 02, 2006, 05:21:12 PM »
Quote from: whatboutbob on June 02, 2006, 06:52:31 AM
see...you jest...but i've actually looked into these:

http://en.wikipedia.org/wiki/Faraday_cage
Heh heh  :D

When you build one i'll be your first buyer!
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My H120 build with Recording Enhancements Pack
Some examples of recordings done on H140 with Rockbox

Offline RedBreva

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Re: A simple test everyone with a remote can try - Remote Recording interference
« Reply #14 on: June 03, 2006, 02:17:01 AM »
on the top line 31
on the bottom line 26

With remote unplugged, both channels start to show a signal at about 43
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