Russian Noise diode/tubes, anyone use these?

[rwgast_lowlevellogicdesin]

Ok well like I said I ordered an airspy, hopefully be here tomorrow, from what I can tell from pictures and reviews it is 24mhz-1.8ghz with almost no spurs(some people say it has none.. idk) and 95-110db of dynamic range, it is made buy the SDR# guys and SDR# comes with a program called spectrum spy that only works with the airspy. Using spectrum spy the model I bought will sweep 1ghz of bandwidth in two seconds, the next one up sweeps a ghz per second.

I plan to do all my RF work using the AirSpy along with satcom would anyone disagree the specs above are pretty decent for a $100 sdr or even SA? The RTL dongles will end up getting a BP filter on each one to do a specific task it can handel, ADSB, ACARS, 800Mhz trunking etc...

For a commercial noise source the BBGen looks very good and affordable, and I am glad someone has confirmed the ebay source isn't worthless, although that BBGen looks nice for an extra 40 bucks. Why exactly do you guys say a comb generator is more useful than a noise generator for filter/antenna work? A comb will just make harmonics and you can obviously see if your filtering said harmonics but with a noise source you can see the actual shape of your filter. I have a lot of different LNA's around some for HD over the air with BP filters built in, some just LNA's for TV with no filters, and some decent RF LNA's. One thing I would really like to do is be able to characterize these, either to see there filtering or to see if they have any issues in certain frequency ranges.

Totally of topic but when you buy an HD over the air antenna what frequency are these tuned for? And secondly I have tons of 50ohm and 75ohm stuff im using in different receiver set ups. Is there a transformer that can be easily wrapped or bought that does 75>50ohm, Im not necessarily concerned with any tiny loss in mismatch but some test gear is just screwy when you attach 75 ohm cable/components.

[uncle_bob]

Hi

Give me a day with it and I'll have data on at least a few thousand spurs. It is better than what you have. The claims they make for it are not believable.

Bob

[Villud]

Diode noise, direct-to-noise for the generation of noise in microwave measuring devices.
The design is in a glass shell, coaxial.

filament voltage (I = 40 mA) (1.4 ± 0.2) V
filament current (1.45 ± 0.15) A
Leakage current between anode and cathode ( U= -200 V) <10mA
slope of the current characteristic of the anode ( U= 135 V) <0.08 mA / V
coefficient of nonlinearity of noise (Lambda= 300 m) <10%
capacitance between the anode and cathode (0.57 ± 0.23) pF
Operating time> 500 h
Criteria for evaluation:
change in the heating voltage in comparison with the initial value <30%
change in the heating current in comparison with the initial norm <10%
Limit operating data
filament voltage is 1.2-1.7V
Anode voltage 140 V
Reverse voltage 200 V
Anode current 40 mA
The steepness of the characteristic (I  = 40 mA) 0.1 mA / V
Power dissipated by anode 5 W
Operating temperature range from -60 to + 70 ° C  ( -76 to 158 F)
http://www.radio-komplekt.ru/im/labels/2%C42%D1%28%E4%EB%FF_%E8%ED%F4%EE%F0%EC%E0%F6%E8%E8%29.pdf



 

[Wolfgang]

Hi, I made few noise sources using the russian tube diodes 2D3B and 2D2S
If you're interested, try

https://electronicprojectsforfun.wordpress.com/making-noise/

for more info.

Greetings
  Wolfgang