Search found 662 matches

by glovisol
Sat Jul 13, 2019 6:42 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

More reception examples with non-optimized original cross pallet loop antenna. The peculiar thing, that comes to attention at once, is the low level of backgrund noise: under these conditions, signals at levels of -115 to -120 dBm are easily copied witout problems, even if the S meter shows S1 to S3.
by glovisol
Sat Jul 13, 2019 5:49 pm
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 7391

Re: Evaluating RF filters?

More in-forum references for filter measuremet & evaluation with RSP Spectrum Analyser software: https://www.sdrplay.com/community/viewtopic.php?f=5&t=3943&p=14894&hilit=filter#p14894 https://www.sdrplay.com/community/viewtopic.php?f=5&t=4364&p=14875&hilit=filter#p14875 https://www.sdrplay.com/commu...
by glovisol
Fri Jul 12, 2019 1:37 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

Hi Phil, I slept on it and was even more convinced this morning, so here is my idea, which is probably the re-invention of the wheel, or perhaps there will be 999 reasons why it will not work. I only have to wait until I get back home in August and test it. METHOD FOR PASSIVE BROADBAND MATCHING OF A...
by glovisol
Thu Jul 11, 2019 3:18 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

Phil,

It is not coax at all, it is a short section of electrical twin wire, like zip cord. I wish I had coax here, I have nothing!!

Thank you for your calcs. The picture I see is quite simple:
Antenna loop calc.png
Antenna loop calc.png (11.26 KiB) Viewed 2816 times
by glovisol
Thu Jul 11, 2019 5:57 am
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

Hi Phil & Paul, 1) Very many thanks for the modeling @ 7 Mhz, which is mid-band, as the antenna works fine down to 3.6 and up (best at 14 MHz). The transformer at present is 450 to 1000 Ohm. From your data, at last @ 3.6 MHz, it should be rather 200 to 1000 Ohm, but Z data up to 14 MHz should be nec...
by glovisol
Wed Jul 10, 2019 7:22 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

Hi Paul, I wish to correct my statement on the abnormal difference in sensitivity between the HI Z and the 50 Ohm input. This has been caused by an unsuitable transformer used on the 50 Ohm input, because being far from home I have very limited resources here. I hope to get suitable 50 Ohm transform...
by glovisol
Wed Jul 10, 2019 5:24 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

Hi Paul, Do not worry for the 80+, I will turn 80 in september next....so you are in good company. Detailed instructions with pertinent photos are posted here: https://www.sdrplay.com/community/viewtopic.php?f=8&t=4109&start=20 Just patiently go over the thread until you come to the directions for b...
by glovisol
Wed Jul 10, 2019 1:22 pm
Forum: SDRuno
Topic: Diversity - how does it work?
Replies: 7
Views: 1745

Re: Diversity - how does it work?

To get the HI Z port going would be really tops!!!
by glovisol
Wed Jul 10, 2019 12:45 pm
Forum: SDRuno
Topic: Diversity - how does it work?
Replies: 7
Views: 1745

Re: Diversity - how does it work?

Look here: https://www.sdrplay.com/community/viewtopic.php?f=7&p=16068#p16068 You must go click on SINGLE it will open up so you can click on DIVERSITY. Then it will be all automatic, provided you have two different antennas, one for each 50 Ohm tuner input. You will not believe it, it takes time to...
by glovisol
Wed Jul 10, 2019 12:40 pm
Forum: SDR Antennas
Topic: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna
Replies: 57
Views: 20641

Re: LW-MW-SW Relay Tuned 15' Noise Reducing Vertical Antenna

IMPORTANT Paul I have discovered that I have the best performance using the HI Z input, as I have been doing since yesterday evening and using the following low noise transformer: Toroid core: FT-37-43 (material type 43) Ext. dia.: 0.375" Internal dia.: 0.187" Thickness: 0.125" PRIMARY:5 turns ename...