Search found 140 matches

by ON5HB
Sun May 05, 2019 10:49 am
Forum: SDR Antennas
Topic: PA0RDT Antenna
Replies: 11
Views: 4359

Re: PA0RDT Antenna

Beware that the coax is part of the antenna but if not properly isolated from common-mode-currents it can either make it receive badly or receive a lot of electrical noise from buildings nearby. Typical the thing is placed on a wooden stick and the coax isolated at the ground level, but as far away ...
by ON5HB
Thu Apr 25, 2019 7:23 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

The thing is, why do you need to isolate anything? I asked you several times, yet you never answer. I tested with a 50 Ohm splitter on my wideband websdr and signals went down, a lot. Maybe it works for smallband but it does not when using 1-2MHz wide. Also it doesn't work when using 3 bands, like 0...
by ON5HB
Mon Apr 22, 2019 9:38 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

Think with your own head, do not believe in false prophets, trust what you measure and see...I have gone to walk the dog...take it easy. You do not get it do you? SWR is a non-issue. Antenna-analysers are a non-issue too. They do not say anything and they do not build good antenna's. Example, analy...
by ON5HB
Mon Apr 22, 2019 9:01 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

sdrom33 wrote:The right reply is that nobody in his senses would use a 50 Ohm connector on a 75 Ohm coax....come Mike, stop this nonsense and have a peaceful Easter, :D
And what if you do? How much losses does it give?
Will you notice? If so, how much?
And last. Prove it!
by ON5HB
Mon Apr 22, 2019 8:58 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

Funny is, I installed and MFJ SDR-switch the other day, the RSP1A's have the same signal as before, but the Icom7300 dropped by 10~20db in reception. Why did the Icom drop and the RSP1A's didn't? Bas, it is the rsp1a magic....It receives better because it has no mixers... : :oops: In fact where Sdr...
by ON5HB
Mon Apr 22, 2019 8:56 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

Nowhere in the RSP-1A spec sheet is it stated that the RSP-1A has an input impedance of 50Ω. It does say this under the heading: Connectivity: "Single 50Ω RF connector (SMA)" My non-professional knowledge of this topic suggests that circuit impedance is determined primarily by the source (the anten...
by ON5HB
Mon Apr 22, 2019 4:25 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

What do you mean wrong info and specs? It's not a transmitter but a receiver, as such impedance isn't crucial to good workings. Exactly what I wrote. The official published specifications by Sdrplay say: 50 Ohm input impedance. If you write in so many words it is not so, you are being unfair to Sdr...
by ON5HB
Fri Apr 19, 2019 3:55 pm
Forum: SDRplay related
Topic: FOR FM DX Which modell RSP
Replies: 4
Views: 1200

Re: FOR FM DX Which modell RSP

I tried the RSP1A on FM (3m band) and it's absolutely splendid.
by ON5HB
Fri Apr 19, 2019 3:52 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

sdrom33 wrote:It could help to know what splitters you are using. The RSP1a input is rated 50 Ohm, why should it be different? Why should sdrplay give wrong info & specs?
What do you mean wrong info and specs?
It's not a transmitter but a receiver, as such impedance isn't crucial to good workings.
by ON5HB
Thu Apr 18, 2019 4:31 pm
Forum: General
Topic: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz
Replies: 36
Views: 7561

Re: 3 dB HYBRID COUPLER/ISOLATOR FOR ANTENNA SPLITTING 100 KHz -10 MHz

I tested a splitter for the RSP1A. Normal situation is T-connectors to 3x RSP1A. I tried an splitter 5-2500MHz, splitted and the signals went down a lot. This makes me believe that the input of the RSP1A is not 50 Ohm but very high impedance. My splitter made a big impact on the signals, where my de...