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Return to top of page · Post #: 1 · Written at 8:35:11 PM on 29 January 2018.
	Tallar Carl Location: Latham, ACT Member since 21 February 2015 Member #: 1705 Postcount: 2174
Does anyone here have a design for a efficient long distance antenna. Whether it be active loop or other. I would like to know how to get the best signal. Even if its a commercially available kit please.

Return to top of page · Post #: 2 · Written at 3:04:37 PM on 30 January 2018.
	Ian Robertson Location: Belrose, NSW Member since 31 December 2015 Member #: 1844 Postcount: 2476
What frequencies Carl??

Return to top of page · Post #: 3 · Written at 3:07:22 PM on 30 January 2018.
	Tallar Carl Location: Latham, ACT Member since 21 February 2015 Member #: 1705 Postcount: 2174
AM or shortwave. I just wish to get the best out of my antique radios.

Return to top of page · Post #: 4 · Written at 3:55:29 PM on 30 January 2018.
	Johnny Location: Hobart, TAS Member since 31 July 2016 Member #: 1959 Postcount: 563
As long a piece of wire as you can get, then a matching/tuner to the radio. RTH had a passive project which would suit you purposes, and also an active one with as I can remember one transistor RF amp. When I get a chance will try to find these RTH projects. Maybe early 60's or 70's. JJ

Return to top of page · Post #: 5 · Written at 4:35:36 PM on 30 January 2018.
	Ian Robertson Location: Belrose, NSW Member since 31 December 2015 Member #: 1844 Postcount: 2476
I have a big problem with high levels of noise at my place, that seems to emanate from the basement power switchroom for the building. But up at the back fence it's fairly quiet. So I ran some RG59 along the side fence and some hookup wire along the timber back fence (suburban townhouse, backs onto Forest Way). Hookup wire connected to co-ax inner, shield to ground at radio end, inner to antenna. Result: Noise nearly gone, signal strength rolls off as you go up the band. A good result, I can now actually listen to 630 and 702! Previously my S:N on 702 was 0 db (i.e. noise equal to signal - actually it's a bit worse than that), now about 30db. It needs a proper matching transformer and the shield grounded at the antenna end. JJ, I'd be interested in that too, when you find it.

Return to top of page · Post #: 6 · Written at 5:49:11 PM on 30 January 2018.
	Tinkera123 Location: Melbourne, VIC Member since 5 October 2009 Member #: 555 Postcount: 466
Yep, me too, please. ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ Cheers, Ian

Return to top of page · Post #: 7 · Written at 7:34:13 PM on 30 January 2018.
	Tallar Carl Location: Latham, ACT Member since 21 February 2015 Member #: 1705 Postcount: 2174
Sounds like what I need

Return to top of page · Post #: 8 · Written at 8:16:29 PM on 30 January 2018.
	Marcc Location: Wangaratta, VIC Member since 21 February 2009 Member #: 438 Postcount: 5389
The Yaesu 7700 has an antenna attenuator & Impedance matching box. Damn good if you can find one. I do have an RCA pdf on antenna lengths. There is such a thing as a long wire antenna that is too long. I am rural, the Yaesu was operating at one stage on a 50m long wire antenna. Workshop; currently around 20m & that brings in 2CH (with some fading) here 520 Km (as the crow flies: Night). These are extremely elaborate affairs, using farm electric fence (7KV) insulators & 2.5mm fencing wire as the active element. Down-lead is clamped with electric fence line taps, but does have a terminal in the end of the external wire. Seeing that we discontinued the over-head power line I now have its insulators, for any new antenna. Tension in the 50m one was maintained by what is loosely described as halyard & dead weight. That allowed some give when hit by flying objects. Marc

Return to top of page · Post #: 9 · Written at 8:36:42 PM on 30 January 2018.
	Johnny Location: Hobart, TAS Member since 31 July 2016 Member #: 1959 Postcount: 563
OK, A quick look at the index. As regards antenna/aerial tuners/couplers, pre amps, improvements for B/C reception ect. RTH April 1948 pge 35 Aug 1952 pge 36 July 1953 pge 76 Jan1957 pge 40 June 1957 pge 89 EA Jan 1968 pge 40 Oct 1976 pge 63 July 1979 pge 49 Aug 1990 pge 152 Nov 1991 pge 74 (pre amp) Dec 1995 pge 58 (active ant) Nov 1996 pge 58 (AM loop ant) Nov 1998 pge 64 (broadcast band ant tuner) Happy browsing, JJ

Return to top of page · Post #: 10 · Written at 8:44:25 PM on 30 January 2018.
	Johnny Location: Hobart, TAS Member since 31 July 2016 Member #: 1959 Postcount: 563
Additional info, At home for mainly Amateur radio I use a large loop antenna. This is via an open feeder line to balanced tuner, hence to receivers and TX's. Being a totally balanced system it is noise cancelling, and being as large as the block can handle, is vey useful even right down to the broadcast frequencies. JJ

Return to top of page · Post #: 11 · Written at 8:59:47 PM on 30 January 2018.
	STC830 Location: NSW Member since 10 June 2010 Member #: 681 Postcount: 1301
Found these links in June '17. Might be informative. http://vintage-radio.com.au/default.asp?f=2&th=812

Return to top of page · Post #: 12 · Written at 4:45:12 PM on 31 January 2018.
	GTC Location: Sydney, NSW Member since 28 January 2011 Member #: 823 Postcount: 6761
The Yaesu 7700 has an antenna attenuator & Impedance matching box It's the FRT-7700. I have one for my FRG-7700 receiver.

Return to top of page · Post #: 13 · Written at 7:21:44 PM on 7 June 2024.
	STC830 Location: NSW Member since 10 June 2010 Member #: 681 Postcount: 1301
Have found these links for active loop antennas of novel design, and post without comment, apart from that they are wideband, in case anyone is interested. https://active-antenna.eu/tech-docs/3_ActiveAA_Antena_11.pdf http://active-antenna.eu/tech-docs/1_ActiveAA_DandS_20.pdf https://active-antenna.eu/amplifier-kit/faq-aaa-1b/ http://www.lz1aq.signacor.com/docs/wsml/wideband-active-sm-loop-antenna.htm

Return to top of page · Post #: 14 · Written at 2:54:06 PM on 8 June 2024.
	STC830 Location: NSW Member since 10 June 2010 Member #: 681 Postcount: 1301
Will make a comment. I saw a photograph of a radio with a crossed loop antenna in Facebook, Tallar Francis Carls page: https://scontent-syd2-1.xx.fbcdn.net/v/t39.30808-6... This sent me thinking again about an idea I had for a crossed loop antenna somewhat like those used for direction finder. Such antennas also have an interrorgating coil remote from the antenna that rotates to find signals detected by the crossed loops. So a loop antenna that doesn't need mechanical rotation wherever it is mounted. But the links in post 13 are a different idea - mostly how to make a low noise active antenna.

Return to top of page · Post #: 15 · Written at 9:24:30 AM on 9 June 2024.
	STC830 Location: NSW Member since 10 June 2010 Member #: 681 Postcount: 1301
Another loop, this time shielded, and by an Aussie. Humerous, note the arnstrong rotator and claimed vampyre repellant quality. https://users.monash.edu.au/~ralphk/shielded-loop-antenna.html

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