Search found 85 matches

by ai4i
Fri Apr 02, 2010 7:05 pm
Forum: FM Radio
Topic: TV and FM IF spacing
Replies: 9
Views: 1854

TV and FM IF spacing

Was doing some math and came up with this curiosity. In this post analog TV world, my question is only academic, but here goes: In Miami, we had a full class C FM at 98.3 co-located with a full power channel six. Didn't this create a potential for interferrence with the TV audio being 10.55 MHz belo...
by ai4i
Thu Mar 04, 2010 5:11 pm
Forum: Administrator Announcements
Topic: Important Notice: WHEN POSTING LINKS
Replies: 2
Views: 7817

Re: Important Notice: WHEN POSTING LINKS

We also prefer to embolden our links.
by ai4i
Sun Nov 01, 2009 9:44 am
Forum: AM Radio
Topic: Synchronous Amplifiers
Replies: 27
Views: 4572

Re: Synchronous Amplifiers

I have to admit, my trip odometer is in sync with the main odometer, all my clocks are kept to within a fraction of a second of each other, and The Tick is my favorite radio station. I trace this back to my childhood when my dad left the room during a presidential address and I turned the TV volume ...
by ai4i
Sat Oct 31, 2009 5:16 pm
Forum: Digital Radio
Topic: Confused about HD signal strengths
Replies: 9
Views: 4153

Confused about HD signal strengths

I was surprised / confused to recently find that some channels within a digital stream are more receivable than others. I tuned into a local HD3 which was choppy, tuned to the same station's HD2 and it held rock solid. Of course channels within a digital stream have different bandwidth, frequency re...
by ai4i
Fri Sep 25, 2009 6:27 am
Forum: FM Radio
Topic: When is enough enough?
Replies: 8
Views: 1474

Re: When is enough enough?

I have been referring only to the noise that comes popping out of my speakers from propagation. On another board, I recently posted that people driving within the five burroughs of NYC should experience minimal difference in recovered audio when their favorite station drops 10dB in power. The new st...
by ai4i
Thu Sep 24, 2009 7:22 pm
Forum: FM Radio
Topic: When is enough enough?
Replies: 8
Views: 1474

Re: When is enough enough?

With SatRad's 10-12kHz frequency response and swishy codecs? ;) Multipath is a function of the route the signal takes from the transmit antenna to your antenna...but unless you rig up a complicated diversity receive antenna the chances of eliminating it are low. Having said that, I can't believe th...
by ai4i
Thu Sep 24, 2009 4:53 pm
Forum: AM Radio
Topic: When is enough enough?
Replies: 7
Views: 1207

Re: When is enough enough?

I would not say that 5mv/m is a "punchy" signal as the old 25mv/m requirement was. My experience is that for two stations with the same field strength, however it is derived (distance, power, DA) the station higher up on the dial will be more receicable in areas such as within and between large buil...
by ai4i
Thu Sep 24, 2009 4:47 pm
Forum: FM Radio
Topic: When is enough enough?
Replies: 8
Views: 1474

Re: When is enough enough?

But what about driving around a city and not wanting to hear picket fencing. I have a decent aftermarket stereo system in my car but have not yet replaced the window dummy load with a real antenna. I drive in the 60db contour of a classical music station and after having satrad all these years, the ...
by ai4i
Wed Sep 23, 2009 6:57 am
Forum: FM Radio
Topic: Inter-station mixing
Replies: 11
Views: 1427

Re: Inter-station mixing

Do HDTV tuners incorporate the same IF structures that analog tuners do?
Not the intercarrier system, so nix the 41.25 MHz part, but what about 45.75 MHz part?
I remember thinking I had received a station that turned out to be another station fifteen channels up.
by ai4i
Wed Sep 23, 2009 6:43 am
Forum: FM Radio
Topic: When is enough enough?
Replies: 8
Views: 1474

When is enough enough?

What is the ideal signal strength for an FM broadcast station?
70dB, 80dB, enough to warn listeners not to connect antennae to their radios?
by ai4i
Wed Sep 23, 2009 6:38 am
Forum: AM Radio
Topic: When is enough enough?
Replies: 7
Views: 1207

When is enough enough?

What is an ideal signal strength for stations on the standard broadcast band?
25mV/M, 1v/M, enough to shake tooth fillings?
Does it matter where on the band it is?
by ai4i
Wed Sep 23, 2009 6:05 am
Forum: AM Radio
Topic: Expanded band
Replies: 4
Views: 799

Re: Expanded band

Except for low power community stations. As their short antennae work pretty well up there, metric tonnes of them have sprung up in every airport, state park, federal park, highway under construction, town, village, and hamlet from sea to shining sea. Their audio is horrible, the announcers are wors...
by ai4i
Mon Aug 31, 2009 4:58 pm
Forum: Digital Radio
Topic: Eventual digital power?
Replies: 2
Views: 2205

Eventual digital power?

Will stations always be stuck with 1% digital power, or even 10% digital power, or will they, perhaps after their hybrid phases end, be able to resume operation at something more akin to their analog power levels? Maybe better receivers will help, but I am disappointed with the decreased range of th...
by ai4i
Sat Aug 22, 2009 5:08 pm
Forum: AM Radio
Topic: C-Quam / Motorola 1310
Replies: 9
Views: 1882

Re: C-Quam / Motorola 1310

Leonard's system was better...at higher modulation levels... I believe that if a C-Quam station were running asymmetric modulation, the balance got shifted off center. Another side benefit incidental to the system was that Kahn decoder chips are a good cheap way to add synchronous detection to cons...
by ai4i
Sat Aug 22, 2009 7:13 am
Forum: AM Radio
Topic: C-Quam / Motorola 1310
Replies: 9
Views: 1882

Re: C-Quam / Motorola 1310

The platform motion never helped, either.
I liked Kahn simply because the stereo range was identical to the monaural range.
One thing I will say in C-Quam's favor, the range was a lot better than IBOC.