Search found 662 matches

by glovisol
Fri Aug 17, 2018 6:58 am
Forum: General
Topic: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS
Replies: 30
Views: 20861

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Preliminary tests of front end High Pass filter I enclose two comparisons of reception with and without HP filter on 40 and 20 m. These have been done with a makeshift 15 m long wire antenna and a water pipe ground while on a flat in a sea resort, so they are by no means definitive, but give some i...
by glovisol
Wed Aug 15, 2018 1:35 pm
Forum: General
Topic: SDRuno S-Meter = S5 With No Antenna
Replies: 13
Views: 7579

Re: SDRuno S-Meter = S5 With No Antenna

Hi Mark,

Herewith uploaded same table as in previous post, but for frequencies ABOVE 30 MHz....

Cheers,

glovisol
by glovisol
Wed Aug 15, 2018 1:29 pm
Forum: General
Topic: SDRuno S-Meter = S5 With No Antenna
Replies: 13
Views: 7579

Re: SDRuno S-Meter = S5 With No Antenna

Hi Dick, Just to clear confusion I am enclosing the table showing the relationship between "S" units and received signal strength (power) in dBm. As far as my experience goes, with the RSP2pro and with the RSPduo, the "S" units shown on the meters correspond to the received dBm with faultless precis...
by glovisol
Sat Aug 04, 2018 7:04 pm
Forum: General
Topic: Testing RSPduo receiver sensitivity with noise generator
Replies: 51
Views: 28687

Re: Testing RSPduo receiver sensitivity with noise generator

Hi Martin, I have carefully gone over the literature you suggested and these products are of very good professional quality for receiver sensitivity measurements and for this use they have output levels in the order of -90 dBm. My question is as follows: do you know of any supplier who markets a muc...
by glovisol
Tue Jul 31, 2018 10:30 am
Forum: General
Topic: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS
Replies: 30
Views: 20861

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

Application of the high pass noise filter to build a balanced input for the RSP1A, as anticipated in the previus post. This scheme allows for best ground separation. One side of the balun's input is connected to the antenna's ground. Connection between antenna and balun may be also done using a bala...
by glovisol
Mon Jul 30, 2018 5:37 am
Forum: General
Topic: hardware reset, or is my RSP2 bricked?
Replies: 4
Views: 2787

Re: hardware reset, or is my RSP2 bricked?

It looks very unlikely to me that water among USB terminals could damage the RSP2 USB interface, unless you were drinking salt water. You should check the laptop PSU for possible mains leakthru to laptop's common ground, also extremely unlikely. I would open a ticket with SDRplay tech assistance: it...
by glovisol
Sun Jul 29, 2018 3:00 pm
Forum: General
Topic: Some more receive only transformer info
Replies: 0
Views: 2286

Re: Some more receive only transformer info

The post by Nulluser00, who dug up very interesting technical information on antenna transformers, gives me the opportunity to further comment on the relationships among: - low noise coupling between antenna and receiver, - wide band coupling between antenna and receiver - receiver's dynamic range a...
by glovisol
Sat Jul 28, 2018 6:52 am
Forum: General
Topic: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS
Replies: 30
Views: 20861

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

High pass n = 6 calculated filter performance is shown below. Attenuation in blue & return loss in red.
by glovisol
Fri Jul 27, 2018 11:16 am
Forum: General
Topic: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS
Replies: 30
Views: 20861

Re: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS

The advantages of the high pass noise filter can be extended to receivers equipped with the 50 Ohm input only. The uploaded schematic is for an umbalanced 50 Ohm input / 50 Ohm output. Balanced antenna input can still be achieved by placing a balun at the filter's input and isolating the grounds, as...
by glovisol
Thu Jul 26, 2018 7:21 am
Forum: General
Topic: Testing RSPduo receiver sensitivity with noise generator
Replies: 51
Views: 28687

Re: Testing RSPduo receiver sensitivity with noise generator

Hi Martin,

Please accept my compliments and thanks for your most interesting and informative post. You opened up a vista on available noise and measurement devices completely unknown to me and probably to many others using this Forum.

Thanks again,

glovisol