Greetings,
We maintain a private cable system for a small retirement community in Hanover PA. We have a mix of satellite and off-air channels. Prior to the digital change, we were able to get an OK off-air signal from the Baltimore stations. Now that conversion is finished, we have chronic troubles with reception of WJZ 13 from Baltimore. Here is link to tvfool
report:
Pre transition, we were using WJZ's analog broadcast RF 13 and signal was OK. During transition, WJZ was broadcasting digital in UHF and all was good.
Since June 2009 transition date, WJZ moved their digital back to CH13 RF space - and we've been fighting it ever since. Signal level on 213MHZ at antenna mast as measured on my Sadelco meter is -24dBmV. Much of the time, signal is fine. Then we get tiling and picture breaks up. Digital demod indicates a 20dB SNR - which should be OK. I suspect that combo of marginal signal and multipath are to blame. All the residents know is that it used to work fine and now it doesn't. And it's my fault!
Hardware setup is as follows:
-Blonder Tongue BTY-10HB single-frequency antenna (for channel 13) roughly 40' above ground level.
-Blonder Tongue CMA-HB VHF preamplifier on mast
Roughly 250' of RG11 to headend
-Blonder Tongue PS-1536 Preamp power supply
-Toner 3-way splitter:
Leg 1 to Drake DAD860 digital demodulator for WJZ (RF13) (converts to baseband, then we re-modulate on our in-house cable plant)
Leg 2 to Blonder Tongue 8VSB to QAM transcoder (we transmit same signal on QAM on our private cable plant)
Leg 3 to a Drake DAD860 digital demodulator for WBAL (RF 11) that is broadcast from the same tower as WJZ. No problems with this channel!
Drake (digital demodulator mfr) says that I should try a newer consumer-grade set-top box to see if newer chipset better deals with multipath. So - any recommendation on a newer set-top box that has tuner that may be better than others? It appears that the set-top box market has fallen off a cliff in the past year...
We are considering a second stacked antenna to help eliminate multi-path, however that's a fairly large nut to crack.
Due to FCC regs, we can't simply get this station off of satellite because we're in a different market area.
So, advice on set-top box and any other suggestions are welcome.
Thanks!
Mike