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WMAL-AM signal

G

GeoffR

Regular Participant
WMAL is diplexed with WWRC from the Gaithersburg area these days, right? After they sold the land that the WMAL sticks used to be on?

Is the signal as bad as I thought it was last month going back and forth on 295 on the East side of Washington? Signal strength was bad (compared to the other main DC AM signals) and it had a whistle on it (that I assume is there because of it being co-located with WWRC?). Or am I wrong and it was just the car radio in my rental that made it sound so bad?

My recollection of the previous signal compared to what they have today seems like it is a big downgrade.
 
I believe they officially moved earlier in the year. I imagine this is why they have the FM simulcast.
 
GeoffR said:
WMAL is diplexed with WWRC from the Gaithersburg area these days, right? After they sold the land that the WMAL sticks used to be on?

Is the signal as bad as I thought it was last month going back and forth on 295 on the East side of Washington? Signal strength was bad (compared to the other main DC AM signals) and it had a whistle on it (that I assume is there because of it being co-located with WWRC?). Or am I wrong and it was just the car radio in my rental that made it sound so bad?

My recollection of the previous signal compared to what they have today seems like it is a big downgrade.
Click to expand...

It's a significant downgrade in coverage, due to the location and other factors.

Any whistle is caused by some other issue. Diplexing does not cause whistles; when stations are very close on the dial there may be, at most, very narrow bandwidth on both stations. But 630 and 980 are far apart on the dial, so a well designed system should have good bandwidth and no interference.
 
You're right about Gaithersburg "area," because it's about ten miles WEST of Gaithersburg. In other words, it's half way to Frederick. Terrible location. They have obviously run up the white flag on this station. No wonder you can't receive them on the east side of town. The antenna used to be in Bethesda, but that land is way to valuable. Don't know why they didn't diplex on the Red Zebra site on the Anacostia. Probably protecting someone.
 
TheBigA said:
Don't know why they didn't diplex on the Red Zebra site on the Anacostia. Probably protecting someone.
Click to expand...

Diplexing 570 and 630 is pretty difficult. I don't recall any diplexed directionals that are so close, although I recall one of the non-directional Honolulu diplex partners being that close at one time.

Another consideration is that the tower layout for Red Zebra may not work for the other signal.
 
DavidEduardo said:


It's a significant downgrade in coverage, due to the location and other factors.

Any whistle is caused by some other issue. Diplexing does not cause whistles; when stations are very close on the dial there may be, at most, very narrow bandwidth on both stations. But 630 and 980 are far apart on the dial, so a well designed system should have good bandwidth and no interference.
Click to expand...

David, WWRC and WMAL are 570 and 630 so they are close on the dial (not 980 and 630). I never checked out the signal for WWRC on the East side, but WMAL-AM did sound very narrow on the car radio.
 
GeoffR said:
David, WWRC and WMAL are 570 and 630 so they are close on the dial (not 980 and 630). I never checked out the signal for WWRC on the East side, but WMAL-AM did sound very narrow on the car radio.
Click to expand...

Sorry, I forgot about the flip in calls on 570.

Essentially, to diplex 570 and 630 one has to build a tuner for each that rejects the other and tunes each tower to the desired frequency. It should be flat out +/- 10 kHz, and then roll off very fast. The problem is that it will be hard to get a flat fundamental and such a sharp cut-off without the roll starting off before the 10 kHz point. So practical design considerations will make each of the stations rather narrow band... but heck, it worked for analog phones for a century.

They probably think that since both stations are talk that it does not matter, but the decrease in "crispness" is very fatigue-inducing.
 
Night signal dropped on the eastern shore but surprised I still hear it. I'm not in WMAL's market though, where it counts (and everyone listens to the FM anyways :) )
 
DC is definitely one of those towns where AM has died out years ago. When WTOP stopped broadcasting on 1500, the bell was tolling. When WMAL simulcasted on 105.9 in 2012, it was officially dead.

WMAL was the only AM station (along with 980 and maybe 1500) were really the only two stations that could cover the sprawling DC market...in 1985. It’s grown by leaps and bounds (especially to the South and West) in the past 30 years. Combine that with poor ground conductivity and the usual interference...not good. I frequently end up in the fringe suburbs of Northern VA, and DC AMs are virtually nonexistent—especially after sunset.

When I was out there a couple months ago, there was no hint of WMAL on 630 in the daytime. You could at least flesh out a signal before in the day. WMAL-FM, on the other hand, was crystal clear down there!
 
and it had a whistle on it...
Click to expand...

This is likely due to microprocessor interference.

I have the same issue inside my house on AM 630 and AM 1270 whenever my DVR/cable box is plugged in.

I've owned cars, too, where a "whistle" is heard on multiple low-band AM frequencies.
 
Speaking of WMAL...
Frank Harden, of the long time morning show, Harden and Weaver, died a few months back. Jackson Weaver, the voice of Smokey the Bear, died back in the early 80s.
I didn't see a earlier post about this...sorry if this is old news.
 
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