Search found 662 matches

by glovisol
Sat Oct 20, 2018 7:13 am
Forum: General
Topic: RSPduo problem in the 15 m band
Replies: 2
Views: 1795

RSPduo problem in the 15 m band

While working in HF I have always been using the HI Z balanced input. In the last few days, to investigate antenna noise and the NR function, I have started using the Tuner 50 Ohm input as well, using a transformer type balun made with a type 43 Ferrite toroid, 10 mm dia., 10t primary & 4t secondary...
by glovisol
Fri Oct 19, 2018 6:17 pm
Forum: General
Topic: Noise reductor adjustment
Replies: 8
Views: 3587

Re: Noise reductor adjustment

Hi Mike 2459, apologies, you are quite right. It takes 10 seconds approx., but then the action of the slider at 200 is quite noiceable! Thanks. Amended 20/10/18: The NR device has two response times: there is an immediate and very noticeable partial reduction effect, followed by a final adjustment w...
by glovisol
Fri Oct 19, 2018 5:12 pm
Forum: General
Topic: Noise reductor adjustment
Replies: 8
Views: 3587

Re: Noise reductor adjustment

With my RSPduo and RDSuno 1.23 the slider does not seem to work, even if I wait a few seconds. However the noise reduction is very good, as shown in the enclosed PC screens with oscilloscope. Noise is reduced by 12 dB from 80 to 20 mVp.
by glovisol
Fri Oct 19, 2018 2:06 pm
Forum: General
Topic: Noise reductor adjustment
Replies: 8
Views: 3587

Re: Noise reductor adjustment

I omitted to mention I am using the RSPduo with SDRuno.
by glovisol
Fri Oct 19, 2018 2:03 pm
Forum: General
Topic: Noise reductor adjustment
Replies: 8
Views: 3587

Noise reductor adjustment

The Noise Reductor switch (NR) is very effective in removing not only white noise, but even interference tones, etc. when turned ON. However the slide type NR green colour adjustment does not seem to have any effect in whatever position from 0 to 200. In other words the NR noise cancellation effect ...
by glovisol
Wed Oct 17, 2018 8:57 am
Forum: General
Topic: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE
Replies: 13
Views: 7289

Re: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE

EXCESSIVE ANTENNA ATTENUATION EXAMPLE If antenna noise floor with attenuation inserted drops to a level near or below the terminated noise floor, the attenuation should be reduced or removed. In the enclosed screen shot the antenna noise conditions are such that the noise floor has dropped to -125 ...
by glovisol
Wed Oct 17, 2018 8:18 am
Forum: General
Topic: RSP RECEIVER LOW NOISE HF OPERATION WITH LONG WIRE ANTENNAS
Replies: 30
Views: 19451

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

NOISE BLANKER EFFECTIVENESS DEMO The Noise Blanker performance of the RSPduo, according to my experience, is extremely good. On the 80 m band, where impulse noise in daytime is sometimes so strong as to blot out weak signals, the NB totally removes it without affecting receiver's sensitivity. Compa...
by glovisol
Fri Oct 12, 2018 12:06 pm
Forum: General
Topic: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE
Replies: 13
Views: 7289

Re: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE

Here below conversion tables dBm to power in mW and to voltages in uV for Z = 50 / 600 / 1000 Ohm system impedances, using: P = 10^(dbm/10) [mW] V = RADQ ((P*10^3)*Z) [uV] where RADQ is the Excel notation for Square Root Finally it has come to my mind that input attenuation has the additional advant...
by glovisol
Wed Oct 10, 2018 11:37 am
Forum: General
Topic: ASSESSING THE PERFORMANCE OF THE RSP RECEIVER SYSTEM IN HF
Replies: 24
Views: 13254

Re: ASSESSING THE PERFORMANCE OF THE RSP RECEIVER SYSTEM IN HF

The enclosed graph summarises Radio Noise evaluations, data and measurements discussed in this thread.
by glovisol
Tue Oct 09, 2018 7:09 am
Forum: General
Topic: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE
Replies: 13
Views: 7289

Re: OPTIMIZING RSP RECEIVER OPERATION WITH ANTENNA NOISE

In this post I am giving noise results on HF frequency bands averaged over the past september month. Measurements done every day at 21:00 Local time ( 19:00 GMT) BEVERAGE ANTENNA MODEL CHARACTERISTICS & SPECIFICATIONS Antenna location: Monferrato, Piedmont, Italy - wine country - 2.5 km from nearest...