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Thanks!!
I recapped the other mod, and replaced the bigger rectifier diodes, it's noticeably better, and able to program it for UHF frequencies now, but it still has issues with reception, it's still weak, not as weak as it was before but still much weaker than my second mod.. I did order up the three transistors, and the smaller rectifier diodes, I'll try replacing those tomorrow to see if it makes a difference.. With the bowtie I'm able to get reception about a block radius with an area where it's completely dead.. I thought it would go a bit farther with UHF..
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Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet.. Last edited by tvcollector; 02-28-2015 at 07:29 PM. |
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Quote:
Two other things to consider: All antennas are directional to some degree (google radiation pattern of antenna in question, in your case UHF bowtie dipole, to see it), and dipoles have the weakest reception at an angle at which the transmit antenna is pointing at you*. Also the RF power of the BT seems to vary from channel to channel (which is not too surprising given is is hard to make wide band tuned circuits and reflected wave traps completely flat over the whole TV spectrum). *Another side effect of directionality is what IIRC is called polarity mismatch....If the TX and RX dipoles are oriented to face 90 degrees different from each other then minimal signal transfer for the other given conditions will be minimal. I took an antennas elective last year, and despite it being the first time the class was offered and the professor diving way to deep and spending way too much time on the maths of infinitesimal dipoles I did take some useful stuff away from it.
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Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
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