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Radio Road Which tuner to get and getting the most from it. Thank God, for the radio! |
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Radio Road Which tuner to get and getting the most from it. Thank God, for the radio! |
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In Reply to: overpowering BAD station nearby!! posted by jsjazz on November 11, 2006 at 05:48:06:
1 A longish one pointed at the LI station on 88.3, and t'other say a 3 to 6 element - DIY yagi - cut FOR 88.1 and pointed at the local 88.1 transmitter.(You could also add a high Q stub to the larger antenna - that is tuned to 88.1 - to tune it out a bit NB this option may affect 88.3! the second antenna idea could too but it is less likely - in theory!)
????
1a
you connect the second 'tenna out of phase - at the combiner - using 300 ohm ribbon to there - secondary 'tenna signal is out of phase at that connection (OOP) and can cancel a lot of the 88.1meg signal (remaining?) in the combined downlead....... Where1c you - could - ADD a very sharp passive in-line filter if such can be built. NB these are all notchy/bandpass filters set to <250k wide and centred on 88.1meg. IE hairpins!
If you will never listen 'to 88.1' you need not bother to make it's filter switchable. NB being able to invert from one OOP cndiyion to the other to get 88.1 or to combine them in-phase, may be an issue for you3 NB An active filter inside the tuner before the front end, might be able to be sharper and do less damage to the desired signal. SWAG!?
4 DOES yr tuner has the option of switching to a 'narrow' bandwidth / I.F. setting. If it does - and you don't normally use it where you have moved to give it a try, that ought to kill what is left for the tuner's front end. IF not look to tweaking below.
If your tuner doesn't I would suggest a used good-sounding one that does, aligned and tweaked for RF and sound - including 'matched' and 'tighter' filters in the 'narrow' circuit.
5. I nearly forgot - do investigate the polarities of transmission of the two stations (and their transmitted power#). Such information can help with the cancelling antenna idea as the polarities MAY not be the same - some non-matching combinations OUGHT to be easier to cancel.
6. An active mast-head active circuit with a STEEEP bandpass filter - and even a teeny bit of gain at 88.3- might be cheaper than an OOP antenna 2 but a much longer antenna is, IMO, essential.
7. do measure the arc in degrees between the two stations and include it in a documentation of your problem. draw a map - if you can. OR onto a map. #? will help with guesses at field strenghts of both stations at yr place / the gain disparities. Okay?
8. Talk to Ed at APS.
of course your budget is your issue.
Happy to provide advice.
URL's for Yagi formulae?
Articles on narrow-band YAGIS are in the ARRL handbooks/yearbooks in libraries. as transmitting antennas have the same dimensions as do receiving antennas.
WarmestTimbo in Oz
The Skyptical Mensurer and Audio Scrounger'Still not saluting.'
Read about and view system at:
http://www.theanalogdept.com/tim_bailey.htm
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Follow Ups
- It would be possible to use two FM antennas and some careful filtering - Timbo in Oz 16:02:55 11/12/06 (0)
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