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when WZBC shuts down...

I have noticed WMBR being spotty as of late. Thats alright, it clears the way for WRPS 88.3 here on the Lexington/Winchester border.
 
ZBC is on the air with only 30 watts making it to the antenna from the Marti. remote readings went from 880 to 40 when the water got in the trasmission line.

You mean the old Burk TC-8 remote control is displaying 0040 for forward power on the Marti PNP1000? I don't know if I'd trust that number...IIRC the Marti's readings get wildly inaccurate at very low levels; that "wattage number" is just a mathematical representation of 0 to 5VDC (I think) and if 0880 is the "normal" 880 watts TPO, then 0040 represents a very low DC voltage on that meter output.

Presumably what's happening is that water in the xmission line is causing arcing and massive reflected power, and the Marti is folding back to protect itself. If it's folded back that much, it's possible the actual output is practically nil. However, I know from experience that even when the Marti is "off", that's just the PA being off. The exciter is still running at a reduced power and there's enough leakage to let WZBC be receivable on car radios as far away as Kirkwood Rd by the Diocese buildings...maybe 1/2 mile away. I know because I used to live there!

The end result, however, is that if the exciter is still actually running "normally" and the PA is effectively folded back to nothing, I could see the equivalent of anywhere from 5 to 30 watts getting out, though. This is one of those cases where the meters could be right even though they're wrong. ::)

As for clear reception even at reduced power...this is where WZBC being on a relatively clear frequency really helps. Yes, they deal with a lot of first-adjacent crud from WICN and WSMA, but save for WRIU...which is pretty darn far away...there's not a lot on 90.3FM near Boston besides WZBC. And a good radio can pick them up a long, long ways away.

And for what it's worth, I'm sure this summer y'all are reeeeeally glad that A/C was installed in the transmitter closet a year or two ago! Especially this week - ugh! ;D
 
aaronread said:
as far away as Kirkwood Rd by the Diocese buildings...maybe 1/2 mile away. I know because I used to live there!

its getting out.. near Legacy Place in Dedham it rapidly drops off. however at full power, near stoughton into brockton it dropps off, so its getting what, 10 extra miles for all that extra wattage?

i'd like to see them put a 20 or 30 foot carbon fiber pole up on top of 2000 Comm Ave (r whatever really tall building visible from across the reservoir)
 
It is the meter on the transmitter front panel that reads 30 watts. That's as high as one can run the power before it goes into VSWR foldback.
 
carmen said:
i'd like to see them put a 20 or 30 foot carbon fiber pole up on top of 2000 Comm Ave (r whatever really tall building visible from across the reservoir)

The top of 2000 Comm. Ave is not a higher elevation above sea level than the B.C. upper campus dorms off Hammond St. on top of "heartbreak hill", where their antenna is on top of Cheverus dorm.

The ground elevation is much lower on that stretch of Comm. Ave than at B.C. upper campus, so even though the apartment building itself is a taller structure than the dorm, the rooftop is a much lower overall elevation than the dorm rooftop.

In fact, if the tower were there, "heartbreak hill" would block the signal to the west, and Chestnut Hill (the hill with private roads between the reservoir on Beacon St. and Route 9) would block the signal to the south. That building, even with a 30 foot tower, would not be higher than those nearby hills, but "heartbreak hill" is.
 
It is the meter on the transmitter front panel that reads 30 watts. That's as high as one can run the power before it goes into VSWR foldback.

That meter, IIRC, draws its readings from the same voltage tap that the remote telemetry panel provides to the Burk TC-8 r/c. So it's just as accurate/inaccurate.
 
Was anything of the old cable salvageable? It's pretty cheap to pick up a one-bay 300w antenna (like maybe $250) and you could set up an aux site at Cheverus.
 
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