Anybody try one of these out yet?
Nooelec Lana - Ultra Low-Noise Amplifier (LNA) Module for RF & Software Defined Radio (SDR)
- Thread starter 737mech
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I would think you would be inviting interference from commercial broadcast or cellular systems with something that broad banded.
I just received this along with the DC block from nooelec to use with my Tram 1410 discone and HPII. Connecting this right at the antenna would require extra connectors, 5VDC to the preamp, and a weatherproof box for all ot it. I’m not convinced after all this was done that I would notice any improvement from connecting it right at three HPII.
When it is connected, I believe the HPII is being overloaded. Hardly any traffic but when it is removed, normal traffic resumes.
Tried turning on the HPII attenuator which helped but the best signal was with the LNA in a drawer.
When it is connected, I believe the HPII is being overloaded. Hardly any traffic but when it is removed, normal traffic resumes.
Tried turning on the HPII attenuator which helped but the best signal was with the LNA in a drawer.
slicerwizard
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You have to have a low noise floor (i.e. be out in the boonies) to use LNAs like that. Then they'll help somewhat with marginal signals.
Its +20dB of gain is way too much. I expect they will have many unhappy returns, or perhaps its their way of getting uninformed buyers to later purchase an inline 10dB attenuator they will later introduce and charge another $35. I can imagine the marketing line for it…no power needed!
Ubbe
Member
You can never use a 20dB amplifier without attenuating the signal. Its specs say 27dB gain at 50Mhz and 20dB at 400MHz.
You'll have to use a variable 0-20dB attenuator and listen to a weak signal in analog mode and adjust the attenuator to lowest noise. If the gain are too low it will create noise and if the gain is too much it will start to overload by adding noise. If the gain are set even higher it will start to create intermod and you will hear signals from other frequencies being mixed together or totally block reception. There's a fine balance that needs to be set and using filters will always help, like a FM broadcast one and perhaps a pager filter for 150Mhz and cellular for 700Mhz.
You should be able to get a CATV variable attenuator with F connectors for $15 and Scannermaster got one with BNC for $50, which is a bit too much.
/Ubbe
You'll have to use a variable 0-20dB attenuator and listen to a weak signal in analog mode and adjust the attenuator to lowest noise. If the gain are too low it will create noise and if the gain is too much it will start to overload by adding noise. If the gain are set even higher it will start to create intermod and you will hear signals from other frequencies being mixed together or totally block reception. There's a fine balance that needs to be set and using filters will always help, like a FM broadcast one and perhaps a pager filter for 150Mhz and cellular for 700Mhz.
You should be able to get a CATV variable attenuator with F connectors for $15 and Scannermaster got one with BNC for $50, which is a bit too much.
/Ubbe
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