Do you know a lot of people who don't listen to radio?...

[Signpost]

FWIW, when Apple introduced the iPod, radio introduced 12 minute long spot breaks.      Sometimes 2 or 3 of them an hour.       Bad timing:  make radio harder to listen to just as listeners are liberated from its shackles.       Thank God       I DO know teenagers who listen to Jam'n and Kiss 108.          But I also know people in their 20's and 30's who don't own a radio, excepting one in their car.

[Tom Wells]

GRC, I do get to hear radio the way I want, if only because I built a station to sound that way.

I DO expect 20-15,000 hz response out of my AM radios, and don't much use those that won't deliver that.

I'm looking forward to FM stations using the new Omnias that will permit FM to have the same huge psychoacoustic
effect as 150% modulation on AM.

I'll agree that well engineered AM is comfort food for the ears, and note that no matter the era, there have always been some
AM radios that had decent upper end response, and others which were always muddy or just
annoying to listen to.

Fer instance I do NOT like the audio-amp response of the Motorola 1972 AM/FM in my daily driver.
It has  a weird mid-stage iron audio transformer at the output driver stage and sounds odd and compresses dynamics
when turned up.

Etc, Etc.  I see many things that were considered "standards" being freely modified in ways that
cause problems which I am then expected to addrress magically and cure, when marketing, poor design or cheapness is to
blame.  I weary of explaining to people why they have chosen things that work poorly or not at all, and then I'm
expected to make thm work acceptably.
So many digital things are still firmly rooted in analog sensing devices and some arbitrary sensing voltage,
and the world refuses to acknowledge the analog measurement still necessary.
The digital part is still just on/off switching at an arbitrarily decided level.
As long as I have to be employed as a skidmark with electronic technologies, I will assess the total situation and application.


This is not quite the same thing as trying to bend the world into somethig I want to see it as.

I expect my AM to sound better than an FM, and when it doesn't I'll be on the engineering board complaining about
whatever is keeping that from being the case.


Just put a whip antenna on my wife's Hyundai. Scary-soft sheet metal. Super-high ductility, they blew ALL the dang
carbon out of that stell!  Wow, the drill just ripped and dug while the edges flared and bent!

It's nothing like any of the sheet metal I or any any of my ancestors in Gary Indiana made.
No wonder new cars ding so badly in hail.

The Kenwood HD radio now actually picks up WBBM AM in iboc, and we can hear 910 WGTO in Cassopolis/Dowagiac Michigan.
Seems the windshield excuse for antenna really was as bad as I've always thought.  Hmmmm

Am I still trying to convince myself that water flows downhill?
No, I'm sure of that, but hipness and marketablility seem to follow paths not quite as sure as water "finding" downhill.

If I couldn't make my the sound of what I get from my radios Better in every way than what I could get from
a "sound system generic typename dujour", I wouldn't bother with the excersise at ALL.  I'd be using an Ipod, too. 

[carmen]

I wouldn't bother with the excersise at ALL.  I'd be using an Ipod, too. 

using a phone w/ a soft66 SDR stowed in a leather case originally designed for SONY microcassette, for 0-75 MHz, and a rtlsdr dongle for 75 to ~2ghz.  combined cost sans phone  less than iPod nano. the technology is there, but unless you ask a question like "how can i hear WBZ with a brickwall FFT right before the IBOC sideband ..while on a Red Line train..in a tunnel.. with full quieting", you probably wont go down the portaSDR/coil route. nothing wrong with appliance-operating anyway

still waiting on some ARM binaries from the iBiquity consortium so i can get WBCN-HD. pretty please?

[Tom Wells]

I tried out some of the first software defined radios and was happy with the beahavior above 10 mhz,
but not very happy on anything lower, even with additional rf selectvity and padder to keep overload down.

The method seems to have a lot of extra, unintended frequencies present in the mixer that end up
as birdies,  image responses, etc.
I'm not willing to deal with that , having a Collins 390 A makes it difficult to accept such faults in other radios.

I'd love to hear airchecks from the fone setup you describe. 
Perhaps some mp3 samples of a really difficult situation such as you describe, then another of
several mw AM stations with music content, some stong, at least one weak.

I'd love to hear a sample of a  medium strength mw station while the sdr bandwidth is adjusted to the various
bandwidths and the resulting sound from up/down excursion through the chosen center frequency.

About 20 years ago I built several 1 tube 1 coil regen SW receivers that worked much like the
SDR idea, blast the  signal with wideband noise and rectify....

It works, but gosh dangit I love air-coupled actual transformers, shielding, an actual tuned rf amp stage right there
in the radio.....all things that ended up in radios because it was the best way to do it.

How many parameters are available in "IF" behavior?  Can you "draw" the response curve you want?
How bout if you want an  asymmetric curve, can it be done if you want?

Are there whistles in received AM signal that vary as the tuning is being adjusted?
These are the most annoying to me. As good IF design should have these showing up on 5 khz in most situations.
Having an unavoidable whistle sititng right in the middle of a desired signal passband is simply not
tolerable, especially when the radio istelf is responsible.

I look forward to hearing an example of the AM fidelity this method can deliver.

For my part, I'll make a few airchecks of my part 15 AM, one recorded from rf locally, and another
recorded directly from the car radio's detector stage. a block or so from the house, at night with some 10 khz whistle present.
Maybe few seconds of local 50kw AMs for fidelity reference.


If it sounds as good you describe, I'll be pleased we're "finally getting somewhere" with this method.