Search found 662 matches

by glovisol
Wed Sep 12, 2018 1:10 pm
Forum: General
Topic: Testing RSPduo receiver sensitivity with noise generator
Replies: 51
Views: 26505

Re: Testing RSPduo receiver sensitivity with noise generator

Hi Andy,
You are a keen observer, wrong series values with the attenuator in previous post!!. Better performance, easier to make shown here below.

Apologies,

glovisol
by glovisol
Wed Sep 12, 2018 11:32 am
Forum: General
Topic: Testing RSPduo receiver sensitivity with noise generator
Replies: 51
Views: 26505

Re: Testing RSPduo receiver sensitivity with noise generator

I enclose simple schematic of attenuators for noise test. Keep noise generator supply voltage at +10V or less to avoid damage to noise generator board.

ERRATA CORRIGE: SCHEMATIC REMOVED BECAUSE OF WRONG VALUES. RIGHT & BETTER SCHEMATIC IN NEXT POST!!
by glovisol
Sun Sep 09, 2018 6:28 pm
Forum: General
Topic: Test to determine if receive damaged?
Replies: 7
Views: 3391

Re: Test to determine if receive damaged?

Hi Franko, As stated in the original post, the total attenuation you need is in the order of 92 dB: if you concentrate this attenuation in one attenuator, it is very likely that you will have spurious feedthru: this is why I used two 46 dB type "Pi" attenuators in series. Each attenuator (designed f...
by glovisol
Sun Sep 09, 2018 12:07 pm
Forum: General
Topic: Test to determine if receive damaged?
Replies: 7
Views: 3391

Re: Test to determine if receive damaged?

A simple test using an $12 noise generator and two home made attenuators is described here:

https://www.sdrplay.com/community/viewt ... f=5&t=3352

Cheers,

glovisol
by glovisol
Fri Sep 07, 2018 11:27 am
Forum: General
Topic: Ghosts in the system
Replies: 11
Views: 4431

Re: Ghosts in the system

While you listen to the S7/S9 Colorado stations at 14 MHz, the Californian stations transmitting hi power (1.5 kW) are OVERLOADING your WIDEBAND front end, get multiplied by a factor of 2 and you see them as 14 MHz signals. The proof: listen in the 7 MHz band and check that here no signal is above S...
by glovisol
Thu Sep 06, 2018 3:05 pm
Forum: General
Topic: Ghosts in the system
Replies: 11
Views: 4431

Re: Ghosts in the system

Hi Alex, Most likely your problem is system overload: you can see a clear example here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=3436 In the enclosed PC screen: Near overload @ 7 MHz. The S meter was above 9+40, but the PC screen collecting software reduced it while taking the picture E...
by glovisol
Thu Sep 06, 2018 2:41 pm
Forum: General
Topic: REMOTING RSP VIA USB - PROBLEM SOLVED
Replies: 2
Views: 2775

Re: REMOTING RSP VIA USB - PROBLEM SOLVED

DISTINGUITUR.....DISTINGUITUR, this is the most used word of St. Bonaventura da Bagnorea, summus scholastic philosopher of the Catholic Middle Ages. To what lightning danger are you referring to? A) An induced strike on the long wire antenna will be blocked by the balun transformer, whose primary m...
by glovisol
Thu Sep 06, 2018 6:27 am
Forum: General
Topic: HF weak signal reception in presence of noise
Replies: 10
Views: 5311

Re: HF weak signal reception in presence of noise

Hi Mike 2459, You did not state at what frequency you took the readings. Floor noise variation with RF gain changes with frequency: see Table 1 here https://www.sdrplay.com/community/viewtopic.php?f=5&t=3352 where significant measurement conditions are given and data was measured with IF AGC ON. The...
by glovisol
Wed Sep 05, 2018 3:57 pm
Forum: General
Topic: HF weak signal reception in presence of noise
Replies: 10
Views: 5311

Re: HF weak signal reception in presence of noise

NOISE BLANKER EFFECTIVENESS WITH STRONG IMPULSE NOISE Noise blanker adjustement when in presence of strong antenna noise plus impulsive noise is extremely critical, not to say impossible, without resorting to manual gain and keeping RF and IF AGC OFF. On the contrary, with the AGC's OFF, Noise Blank...
by glovisol
Wed Sep 05, 2018 1:23 pm
Forum: General
Topic: Remote RSP via USB/CAT5
Replies: 27
Views: 10660

Re: Remote RSP via USB/CAT5

Hu guys, I judge this info so important I am also posting it in this thread! Today I received an USB2.0 repeater cable manufactured & sold by LogiLink Germany with a length of 10 m. On Ebay I paid EUR 11.00 for the cable + EUr 7.00 for express courier shipment. Connected the cable between the PC USB...