What is Reddit's opinion of SMA Female to Y Type 2X L MCX Male Right Angle Spliter Combiner Cable Pigtail RG316?

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I just have one of these connected to the SDR's.

https://www.amazon.com/female-right-Spliter-Combiner-pigtail/dp/B015ASUJ48/

Then an SMA-BNC cable to the antenna. Stratux is attached to a window with a suction mount and is powered by a long USB cable to a lighter adaptor.

Interesting. I'll give the laptop test a shot, that's a great idea that I hadn't considered.

I should have clarified - this isn't using any of the stock SDR parts aside from the SDRs themselves. The splitter is this guy.

On the off chance the Y pigtail is bad I also ordered a hardware T combiner for the two pigtails I got with /u/dmurray's antennas.

that's an interesting situation, i won't have all the answers but hopefully i can point you to things you might not know already exist so that you can figure out a good solution.

are you trying to put the dashcam outside? there aren't too many options, but blackvue has truck variants of most of their dashcams. these have longer video cables and are weather proofed.

if you're trying to run wires once for both locations a splitter might help, then you only have to move the dashcam. something like this but with 2 female mcx and 1 male mcx (i couldn't find one with a quick search).

u/helno : any thoughts on how one might use the new UAT with an external antenna? I've used the dual MCX to single SMA splitter (https://www.amazon.com/gp/product/B015ASUJ48/) as suggested in a previous post. With the u.FL-to-SMA pigtail, have you come across a splitter with the different connectors?

Here is what I use. Splitter connects directly to the SDR's and then a single cable straight to the antenna.

https://www.amazon.com/female-right-Spliter-Combiner-pigtail/dp/B015ASUJ48/

https://www.amazon.com/Pigtail-Jumper-coaxial-Quality-Shipping/dp/B00YBQEHRG/

Is this what your looking for:

http://www.amazon.com/gp/product/B015ASUJ48

> Also those split pigtail connectors (http://www.amazon.com/gp/product/B015ASUJ48) bad news? I thought I would save by getting one of those but i'm hearing they might reduce your reception.

It depends. In testing I have done there is phase cancellation within the pigtails if they are connected to something other than their characteristic impedance. Since the dongles do not have a consistent input impedance, they do not match well with the 50 ohm coax splitters. Additionally, the splitter provides minimum isolation between the dongles.

When attached to a good match the splitter will have a 3 dB loss plus cable loss to each port (typically 3.5 dB - 3.7 dB total). Also, the splitter only provides about 6 dB of isolation between the dongles. To see the characterization of a typical cable splitter refer to the Impedance Matching document in Issue 203 on GitHub.

Why is a good match important? If a splitter is attached to a poorly matched termination reflected waves are set up within the splitter. These reflected waves will change in amplitude with the given signal strength and with a phase difference of the incident wave to the reflected wave. For example, if the received signal is at 978 MHz (UAT) and the the dongle impedance at 978 MHz is close to zero Ohms (I’ve measured as low as 10 Ohms with a Network analyzer) up to 100% of the signal will be reflected back to the source 180 degrees out of phase thus cancelling the signal from the antenna. If the coax length from the “Y” or “T” junction (antenna end) of the splitter to the 978 UAT dongle is a multiple of an odd quarter electrical wavelength (1/4, 3/4, 5/4, etc.) and the dongle has a low impedance it will look like an open coax (due to phase cancellation) at 978 MHz from the antenna junction of the splitter to the dongle; even though an ohm meter says there is DC continuity through the coax. This is worse case and in practice the cancellation can be anywhere from 0% to 100% depending on the quality of the dongle’s input impedance, the quality of the coax, and the length of the coax, but most of the time the degradation of the signal is frustratingly somewhere in between.

To paraphrase what ssokol said above YMMV when using a coax splitter.