Audio Asylum Thread Printer
Get a view of an entire thread on one page
|For Sale Ads|
In Reply to: RE: Are both these stations in the same direction? posted by Timbo in Oz on November 22, 2011 at 17:01:32
WRR FM 101.1 is a 98kW station located in Dallas, TX at 184 degrees from true North at a distance of 61.7 miles with a signal level of -50.3dBm.
The offending station is KWRD 100.7 also a 98kW station at 42 degrees from true North at a distance of 4.7 miles with a signal level of -10.6dBm.
I use an outside Winegard FM only antenna with 13 elements oriented to the WRR location in Dallas. This data was obtained from FM Fool's website based on physical address. You can see that the offending station is quite stout. Without an outside directional antenna picking up WRR is a really difficult task for any tuner. About the only other thing I could do on the RF levels would be to put a balun transformer right behind the tuner, convert to 300 ohm twin lead and put a tunable trap there to try to create a suck-out at 100.7 mHz. I don't currently have the needed 9-180pFd variable capacitor to make the trap. If the trap creates too broad a suck-out it could reduce the signal level of WRR making acceptable noise free reception of the desired station worse than it is currently. It might be worth a try though.
I still think that I need a slight boost in the IF gain and selectivity of my TU-915 by changing at least one of the current IF filters using one of Bill Ammons boards that provides moderate gain plus selectivity, or maybe even an extra stage of filter & gain compared to the existing 3-filter arrangement.
A great FM tuner is expensive- just look at high-end Kenwood, McIntosh, Sansui, Accuphase tuners. Being an inexpensive mod, I would simply install the IF filter kit.
and connected out-of-phase with the main antenna, you'd need a combiner on the mast as well. If you are not using a rotator, there's just the issue of vertical spacing on your existing mast, 6ft being the minimum.
Of course the offender would have to be a station you'll never bother listening to! ;-)
Better IF filters -might- do the job on their own, and the tuner has a wide/narrow switch?
Option 2: ONLY IF you have a truly large loft space with a truly long diagonal in the direction of your WRR!? Getting an even bigger signal from it than any retail Yagi or LPD could manage - even stacked. A rhombic wire made from twin lead, with sides well above (double?) the wavelength at 100Mhz of about 10 feet. The existing Wineguard could then be used for an even deeper notch, or for any other station you've wondered about. When the 3 element would be needed for the notch.
If it were me I'd get the filters, then consider how much quieter and clearer I'd like WRR to be, as well. You'd also know how problematic the offender is after the filters.
I've posted the URL for the rhombic article below.
If you've read this, a response is preferred.
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
Oops! I was wrong on the direction of KWRD 100.7mHz, the angle from true North is 346 degrees, which is essentially off the back side of my Winegard FM only antenna. A recheck using FM Fool shows the signal level at my location of this station is -9dBm, a very stout signal.
Post a Followup:
Post a Message!
This post is made possible by the generous support of people like you and our sponsors: