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#61926 - 22/01/2002 03:54 Tuner seek tool
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
I think this has been mentioned before, but with 2.0b7's new Seek Tool, we have a good model for it.

IWBNI we had a Seek Tool for Tuner mode, allowing us to change station using the knob, and ideally also showing us where the strongest signals are.

If this were implemented, it would be a full-screen info mode, like the MP3 seek tool, and so would toggle in a group with Radio and against Off/Line/Transient.
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#61927 - 22/01/2002 04:53 Re: Tuner seek tool [Re: tms13]
prolux
member

Registered: 17/08/1999
Posts: 151
Loc: Manchester, UK
VERY interesting idea.

Initial problems I invisage are:

1) It would require scanning of all the frequencies to produce the graph, a rough estimate John Ripley and I have just come up with is that whilst you are listening to a station building the profile of other frequencies would take about a minute.

2) If you are listening to the radio in the car the signal strengths will be constantly varying as you travel along (N.B. Most people only have tuner modules in the car (if they have one at all)) - Because the entire frequency range takes a minute or so to sample, the signal strengths would have to be carefully averaged over time.

In principle John and I think it is a workable idea, and we like it. However, we are rather busy trying to stabilise the current beta, and therefore new features will have to wait.

Toby

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#61928 - 22/01/2002 05:34 Re: Tuner seek tool [Re: prolux]
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
Taking note of your comment that this is a post-2.0 wish....

I didn't realise it took quite so long to measure signal strengths. I thought I'd read here that it could be done imperceptibly (but more slowly) in the background (that would help address the changing strengths problem) Showing a graph was a wish on a wish, really - a scale with 80, 90, 100 etc (for FM - substitute values for MW range). One thing you could do, though, is highlight frequencies that are in the AF list of the current station, and perhaps measure those. No help if there's no RDS, though...

If this is on the post-2.0 wishlist, then I'm happy. TBH, I'm very pleased that the tuner hasn't just been abandoned since the HSX doesn't have one.
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Toby Speight
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#61929 - 22/01/2002 10:38 Re: Tuner seek tool [Re: tms13]
andy
carpal tunnel

Registered: 10/06/1999
Posts: 5916
Loc: Wivenhoe, Essex, UK
I don't think it a case of it taking a long time to measure the signal, I think it's more that if they did it any quicker you would notice it happening (in the audio output of the station you were listening to).

As I understand it the tuner can only be tuned to a single freqeuncy at a time, so they would have to quickly switch to another frequency and then back to the one you are listening (presumably during the switch the audio output it muted or held at what it was before the switch???). They can only do this quick switch so many times a second before it becomes noticable in the audio output.
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#61930 - 22/01/2002 10:57 Re: Tuner seek tool [Re: andy]
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
So if I was willing to mute the audio for a while, I could have the map more quickly? I'm thinking of the case where I start losing reception of the station and want to find a replacement. By the time I'm looking, we're probably down to one or two bars and it's not worth listening to anyway.

Hmm, perhaps if the tuner is muted (or we're in MP3 or Aux mode), scanning could happen more quickly. Otherwise, it could build up gradually outwards from the current position, the way that MP3 Seek Tool builds up gradually from the left (beginning) of a previously-unplayed track.
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Toby Speight
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#61931 - 22/01/2002 11:05 Re: Tuner seek tool [Re: tms13]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
I like the idea that it could be constantly scanning and updating the signal-strength map in the background, no matter what you're doing.

Well, OK, it wouldn't work too well if you were listening to MP3s and your antenna was down (or the antenna amplifier was not powered).
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#61932 - 22/01/2002 11:11 Re: Tuner seek tool [Re: tfabris]
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
In reply to:

I like the idea that it could be constantly scanning and updating the signal-strength map in the background, no matter what you're doing.

Well, OK, it wouldn't work too well if you were listening to MP3s and your antenna was down (or the antenna amplifier was not powered).




You'd want to have a configurable option (or a setting) to power the antenna at all times, I guess. This issue also comes up when RDS TA (traffic announcements) gets implemented, and you want it to interrupt MP3 or Aux playback.

In case it's not obvious, by "option" I mean something in the config file, and by "setting" something set on the front panel.
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Toby Speight
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#61933 - 22/01/2002 11:17 Re: Tuner seek tool [Re: tfabris]
prolux
member

Registered: 17/08/1999
Posts: 151
Loc: Manchester, UK
The problem with this concept is that there is a whole extra dimension than in the track Seek Tool, namely time.

If you weren't listening to the radio, the profile could be constructed relatively quickly, the limiting factor in this scenario is the I2C bus which is capable of about 10,000 commands per second.

If you were listening to the radio and the profile took say 10 seconds to construct, by the time you've got back to constructing the start of the profile again the signal at that frequency may have changed, but maybe only because you're driving under a bridge.

In short the key to getting this right will be good tweaking of the amount of time the values for frequencies are averaged over, this may need to be different for when you are listening to the radio and when you are not.

(The antenna issue is easy to resolve)

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#61934 - 22/01/2002 11:44 Re: Tuner seek tool [Re: prolux]
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
Toby D (prolux) wrote lots of stuff that all makes sense.

Thanks, Toby.
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