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Old 2-Jul-2020, 6:17 PM   #6
Retired A/V Tech
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,683
Originally Posted by mikecandu View Post
My plan is to have a totally separate system for VHF only reception, hence a VHF antenna.....Besides that even the " rabbit ears" see something on channel 5.

Hello, Mike

The signal is fairly strong, but the HDHR signal quality must be at least 50% with an SNR of at least 15 dB. The symbol quality must be 100%. That might be difficult on VHF-Low where the noise level is very high, which will reduce the SNR.
My pre-amp arrived today. Its small!!

I'll have to figure out what type of coax connector is needed for it.
The connector is SMA Female. I use an SMA to F adapter cable on my SDR:

There is a warning about powering the amp:
Please note the following precaution since the Bias Tee is installed. When powering the device using either the DC header or the USB connector, +5 VDC will appear on the RF output. If your receiver does not have a DC blocking capacitor on its input or some other form of DC voltage protection, this voltage WILL damage your receiver.
If you find that you need the amp and want to mount it outside, it will need to be in an enclosure. If you use it inside you will not need an enclosure, but it must be powered properly. There is a USB cable available to power the amp:
Micro USB Cable for LNA power

If you power it that way, you must add a DC block at the output of the amp.

The alternate way to power the amp is the same as an ordinary preamp would be powered, with a power inserter between the amp and the tuner.
Attached Images
File Type: jpg mikecanduTVFch5-SS_1.jpg (91.3 KB, 558 views)
File Type: jpg mikecanduTVFgpioLNA_1.jpg (158.2 KB, 557 views)
If you can not measure it, you can not improve it.
Lord Kelvin, 1883

Last edited by rabbit73; 2-Jul-2020 at 6:38 PM.
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