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
Search found 662 matches
- Wed Sep 12, 2018 1:10 pm
- Forum: General
- Topic: Testing RSPduo receiver sensitivity with noise generator
- Replies: 51
- Views: 151806
- Wed Sep 12, 2018 11:32 am
- Forum: General
- Topic: Testing RSPduo receiver sensitivity with noise generator
- Replies: 51
- Views: 151806
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!!
ERRATA CORRIGE: SCHEMATIC REMOVED BECAUSE OF WRONG VALUES. RIGHT & BETTER SCHEMATIC IN NEXT POST!!
- Sun Sep 09, 2018 6:28 pm
- Forum: General
- Topic: Test to determine if receive damaged?
- Replies: 7
- Views: 18467
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...
- Sun Sep 09, 2018 12:07 pm
- Forum: General
- Topic: Test to determine if receive damaged?
- Replies: 7
- Views: 18467
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
https://www.sdrplay.com/community/viewt ... f=5&t=3352
Cheers,
glovisol
- Fri Sep 07, 2018 11:27 am
- Forum: General
- Topic: Ghosts in the system
- Replies: 11
- Views: 26097
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...
- Thu Sep 06, 2018 3:05 pm
- Forum: General
- Topic: Ghosts in the system
- Replies: 11
- Views: 26097
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...
- Thu Sep 06, 2018 2:41 pm
- Forum: General
- Topic: REMOTING RSP VIA USB - PROBLEM SOLVED
- Replies: 2
- Views: 11945
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...
- Thu Sep 06, 2018 6:27 am
- Forum: General
- Topic: HF weak signal reception in presence of noise
- Replies: 10
- Views: 28043
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...
- Wed Sep 05, 2018 3:57 pm
- Forum: General
- Topic: HF weak signal reception in presence of noise
- Replies: 10
- Views: 28043
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...
- Wed Sep 05, 2018 1:23 pm
- Forum: General
- Topic: Remote RSP via USB/CAT5
- Replies: 27
- Views: 68497
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...