Quality AM radio

A friend and I were talking for the first time about watch jewels just 2 hours ago. Yours is the first reference I've seen to watch jewels in years.

I think they might still be talking about watch jewels if digital hadn't arrived, though there were tuning fork watches. Didn't they have gears?

It seems to me only the balance wheel (is that it?) and two or three gears beyone it turn enough to need jewels. ????

Reply to
micky
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I"ve always guess that the cheap digital watches were made the same as the better ones, but it turned out they didn't keep good time, so they sold them cheaply. ???

BTW, both my and my friend's Philips DVDR with HDD have clocks that keep time badly, It starts recording earlier and earlier as months go on, so wwhen I went away for 3 months, I had to record 1 minute after it should have stopped, and I should have made it 2 minutes.

Reply to
micky

The only "forbidden" frequencies (as far as radio receiption goes) I've ever heard of, are the UHF frequencies used by the older-generation (analog) cellular phone systems. The FCC prohibited (and still prohibits) making general-purpose radio receivers that can tune to them, reportedly due to influence from the cellphone companies who could then claim that these phone systems were "secure".

As far as shortwave goes... I have never heard of the FCC, or anyone in this country somehow "forbidding" radios from receiving any of these frequencies. Just doing a quick look at multi-band receivers on the market today (a quick web search), most of those which offer shortwave at all have continuous coverage from below 2 MHz up to 22 MHz or more (many to 30 MHz which is the nominal end of the "high frequency" radio range and hence where "short wave" is usually considered to end).

Above 30 MHz, long-distance (e.g. international) signal transmission is difficult and unpredictable... it depends a lot on the state of the ionosphere, which depends on the solar cycle and time of day.

Can you cite the regulation in which they actually mandated this? I've never heard of it.

Ditto for the "forbidden frequencies" - where are the laws or regulations which "forbid" them?

Reply to
Dave Platt

regulations which "forbid" them? "

Poor choice of words, there probably is no actual law or regulation, but fo r some reason manufacturers omit those frequencies.

There is something though because years ago the FCC was considering pulling a station's license because their programming "appeared to be intended for domestic audiences". Need I mention that the station was full of dissident s who were very critical of the US government ?

Reply to
jurb6006

I've never heard of it. "

The both AM and FM thing I remember distinctly due to my exposure to high f idelity. I'm pretty sure it was in the 1970s. A quick Google does not turn up anything on it though, but that is not uncommon. Much of this older stuf f was simply never archived. Suffice it to say I didn't make it up. I didn 't imagine it.

I wonder if I could at least get the date from archives of High Fidelity ma gazine, to which I subscribed for a time. They used Hirsch-Houck (sp) labs to test everything and though AM was no big deal they tested it anyway to s ee if the manufacturer was lying in the manual. Of course the consistently found poor performance, but then they didn't lie about it. The AM section w as there, I bet some people never ever used it.

These old laws and regulations can be hard to find. We've heard about the c razy laws like against French kissing in public, that you can only beat you r Wife on Sunday and all that, but that info is from specialty sites. To fi nd them on an actual government site can be nerve wracking.

Reply to
jurb6006

You know, I was thinking about the solid phone wire, 4 conductors, two twisted pairs, surrounded by a loose fitting jacket. The stuff you run inside walls. But of course I didn't think enough 'cause then I would have thought about the flat 4 conductor interior phone wire used for extensions and the like. Duh. Eric

Reply to
etpm

Probably because it costs something (in engineering and in dollars) to implement a "DC to daylight" design. The manufacturers don't really have any incentive to do this, and include the "missing octave" (above the medium-wave AM band, and below the start of HF at around 3 MHz), because very few of their customers care about this, because there isn't any commercial or social programming using these frequencies. The semiconductor companies which make specialized ICs for receiving middle-wave AM, VHF FM, etc. probably don't make chips specific to these frequencies because there's no commercial demand.

If you want a radio which receives these, they're certainly available "off the shelf". "Communications receiver" radios like the Icom IC-R8500 will do this very well indeed - that one receives everything from 100 kHz to 2 GHz, except (in the U.S.) for those cellphone band frequencies I mentioned.

These receivers aren't cheap, of course.

Or, build any of numerous LF/MF receiver designs out there on the net... a simple MW AM superhet design can be adapted easily enough, or use an NE602 and make a single-chip direct-conversion receiver (add a transistor or two to drive a loudspeaker).

If they were trying to abuse an "international short-wave" station license to do domestic broadcasting, I'm not surprised. The FCC regulations on stations for those frequencies are very clear - they're to be used only for broadcasting programming to other countries. You have to have at least 50 kilowatts of transmitter power, _and_ a directional antenna with at least 10 dB of gain (which means "big!") aimed at the specific area your broadcast is intended to serve.

The FCC points out that the costs are high (maybe a million dollars) and it's not a very efficient way to reach international audiences these days.

The frequency uses are coordinated between the FCC, and other ITU countries, to minimize interference in these broadcasts between countries. I haven't read the ITU regs (a treaty to which the U.S. has been signatory for a lot of decades) but I strongly suspect that the international agreements for these frequencies _forbid_ signatory countries using them for in-country broadcasting... there are other frequencies set aside for that.

The FCC's regulations are quite clear:

§ 73.788 Service; commercial or sponsored programs.

(a) A licensee of an international broadcast station shall render only an international broadcast service which will reflect the culture of this country and which will promote international goodwill, understanding, and cooperation. Any program solely intended for and directed to an audience in the continental United States does not meet the requirements for this service.

These aren't new regs; this section dates back to 1963 and was last amended in 1973.

No, you don't need to mention it, because it's really rather irrelevant. The FCC regulations apply to _any_ US organization that wants to set up an international broadcast station. Dissidents have a right to equal treatment before the law, _and_ they have an equal obligation to respect the rules (or step up and face the consequences for not doing so).

So, if that group of dissidents applies for an international broadcast authorization, asked for a frequency assignment, and then tried to "re-purpose" their station in a way which is _specifically_ prohibited by the regulations, it's not surprising they got slapped... and I have no particular sympathy for them. I expect a similar thing would happen to any other "international" broadcaster that tried a similar stunt.

Reply to
Dave Platt

I find this quite curious, because I subscribed to those same magazines (Stereo Review, High Fidelity, Audio, the Sensible Sound) through the same era, and never read or heard anything about that sort of requirement by the FCC.

I've never seen a reference to such a requirement, anywhere. I've never seen a receiver, tuner, or integrated circuit described as complying with a "Part XXX" requirement of this sort (while they're often tagged as complying with Part 15 rules for RF interference).

I've never heard tell of a manufacturer being cited for failing to comply, or a bunch of illegal FM-only radios/tuners being seized by the FCC, or any company fined for selling them.

And, I know there were a bunch of FM-only tuners and radios being made and sold through that era... Kloss made several FM-only radios, Scott and others made FM-only tuners, I've still got a Dynaco FM-3 in my collection (no AM).

So, I'm not sure what you read. It's possible the FCC may have been _considering_ such a mandate (possibly someone in the AM broadcast industry filed a petition to ask for a rule-making of this sort) and this was mentioned in the magazine, but I don't think I've ever seen any evidence that such a mandate was ever actually implemented. There _ought_ to have been plenty of traces, visible over the years and even now, and I haven't seen any.

If it had been I suspect that it might have been unenforceable, as being outside the FCC's authorized regulatory powers. The FCC has a lot of authority over what can be _transmitted_, and how, but a lot less over what can be _received_ (and I think even less over the question of what must be _required_ to be receivable).

Please pass the info along if you do find it - I'm quite curious.

I suspect _lots_ of people never used it. Even by the 70s, FM (with its better performance and stereo capability) had pretty much kicked AM's butt, as far as quality sound distribution goes.

The presence of the AM section was pretty much a "check-box" item for most buyers, I think. They expected it to be there (because they were used to it) and they'd consider a receiver not having it to be "inferior" and thus less worthy of purchase. That's probably why the manufacturers (1) continued to include it and (2) didn't bother to make it a good one - it had to be there to keep their product from losing sales, but its quality was pretty much irrelevant to those sales.

The devices which didn't have it, were ones which were being marketed to an audiophile crowd, I think, where people wanted the best FM sound for their dollar and didn't care a fig about AM.

Reply to
Dave Platt

My attempted shortwave antenna didn't use that either. It used the round white wire with for separate, unattached conductors inside, each with its own separate insulation. Don't you remember those days?

Reply to
micky

Don't hold your breath. jureb6006 is full of unsubstantiated nutter conspiracies.

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Jeff-1.0 
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Reply to
Foxs Mercantile

There were a few cheap AM/FM/SW receivers on the market in the 1960's that used 10.7MHz for the first IF frequency. Trying to listen to anything within about 2 MHz of 10.7MHz was difficult because of spurious receiver responses from the AM broadcast band. So, there was a hole in the tuning range from about 9MHz to 12.3MHz. Is that what you're talking about?

There was also a move during the AM stereo wars (approx 1980 - 1995) to require AM stereo in all automotive radios. Manufacturers were worried that there might not be a mass market for AM stereo (which was proven correct) and that the general public was better served by having AM stereo shoved down their throat. Similar requirements have been proposed for satellite radio, and HD FM Radio. To their credit, the FCC has rejected all such proposals.

Back to the "Quality AM Radio"... To deal with complaints about lousy mono AM quality, the AMAX certification program was established: "According to the EIA and National Association of Broadcasters, tuners and receivers that are qualified to carry the AMAX stereo certification logo will capture the widest audio frequency response and highest quality stereo separation of AM stereo broadcasts that modern technology can offer. In addition, AMAX tuners and receivers will capture all of the fidelity transmitted from monaural AM stations. Its audio response is more than two octaves greater than a standard AM radio."

So, is your favorite AM stereo tuner AMAX certified? (See Pg 6) Notice that the AMAX spec required a wide/narrow bandwidth IF switch in order to get decent audio quality. I couldn't find anything on how or where to get something certified.

Stations still doing AM stereo: Better quality AM receiver retrofit (using C-QuAM modulation):

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Jeff Liebermann     jeffl@cruzio.com 
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Reply to
Jeff Liebermann

Some more detail on AMAX, improvements to AM broadcasting, and AM stereo:

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Reply to
Jeff Liebermann

Yeah, I remember that wire. I though that the wires in them were twisted pairs though. Not a very high rate of twist though. Are you sure those wires aren't twisted pairs? Eric

Reply to
etpm

Yeah, that's the conventional wisdom. I have a different view. A bigger broadband antenna does not produce a better AM signal. What happens when you install a bigger antenna is that you simultaneously increase the signal and the noise pickup with the SNR (signal to noise ratio) being constant. At BCB (broadcast band) frequencies, the atmospheric and man made noise is quite high. Hearing a distant station with good fidelity and low noise is not so much a matter of having a strong signal, but more a matter of reducing the noise. The noise can be switching power supplies, motors, appliances, and mixing between two or more out of band stations.

The antenna does not need to be huge. See various version of the PA0RDT mini-whip antenna for clues on what can be done with very small antennas:

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Reply to
Jeff Liebermann

I stripped back 6 inches on one occasion, I'm pretty sure, and I saw no twisting.

I'm sure I still have more of it, and I have some new stuff tooMaybe 5 years old.

I bought a new roll of 100' a while back, but I haven't stripped that type of wire back more than an inch or two.

Reply to
micky

So what? American domestic SW stations have been broadcasting to a domestic audience since at least around 1970 when I was entertained by HL Hunt sponsored right wing propaganda on radio station WINB.

It reached a peak around the Y2K period when overtly racist neo-nazi babblers could be found among the end time preachers, conspiratorialists, and other kooks of domestic SW radio.

Domestic SW broadcasting has been a real world fact, if not a legal fact, for decades.

I'm not aware of the FCC enforcing any speech codes or domestic SW broadcasting requirements in modern times. Maybe it's not enforceable? I dunno.

Kookcasters don't have the budget for their own radio station. They buy time on brokered SW stations. A broadcaster like the Jeremiah 33:3 Ministries guy has been kicked off at least a couple of stations for not paying his bills. A real loss for those who need to learn every kooky detail on the Masonic/Alien/David Rockefeller Conspiracy which controls EVERYTHING.

I haven't heard ADV in a while. Sometimes broadcasters go vagabond, sometimes they're just gone.

Reply to
Frank

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