I've got a Bassline with ELRS receiver which comes fitted with a T antenna. It seems to keep a reliable connection beyond what the 1S Walksnail HD VTX does and plenty for what I want. I've been eyeing up getting a Mobula8 for a few reasons and note that the RX antenna is a simple short length of wire. I'm just wondering if there's much of a performance hit with the short wire antenna rather than the T antenna?

IMO the Bassline is a small outdoor biased quad, the Mob8 a big indoor biased quad, hence the chosen as designed antenna differences.

Personally I'd not be looking to extend the Mob8's range, and suspect its std gear is perfectly adequate for its intended purpose, so perhaps the unstated reasons for wanting one you have push the quad away from its "happy place"?

(24-Jun-2024, 10:29 AM)Scro Wrote: I've got a Bassline with ELRS receiver which comes fitted with a T antenna. It seems to keep a reliable connection beyond what the 1S Walksnail HD VTX does and plenty for what I want. I've been eyeing up getting a Mobula8 for a few reasons and note that the RX antenna is a simple short length of wire. I'm just wondering if there's much of a performance hit with the short wire antenna rather than the T antenna?

Are you asking about the antenna on the ExpressLRS or the antenna on the Walksnail VTX. The ExpressLRS antenna main focus is to receiver signal from your hand set. The Walksnail VTX antenna is to transmit video signal to your goggles on the ground.

ExpressLRS protocol generally has very good range depending on how far you plan to fly. A single T antenna will give you good control from your transmitter for a long way. I fly close distance and I have those tiny ceramic antennas and never had issues. For 400 meters and farther I use two T antennas and my RQly is always very good. You will lose telemetry from the receiver way before you lose control from the handset. 

One easy way to test is to turn on telemetry from the receiver and do a flight log on your transmitter. Then you can actually see the RF signal performance. Besides, if you set the transmitter/handset to use dynamic power the transmitter will automatically bump the transmit power up when the RF signal is losing a lot of packets.

Then the VTX antenna on the Walksnail is a totally different issue. It transmitter on 5.8GHz and to me a good antenna is much more helpful with regards to video quality. Most likely you will lose video image quality before losing control data on your ExpressLRS.

The enamel wire should be fine out to maybe 200-300m with ease and probably more. Just make sure it isn't buried inside the canopy. You should be able to do 200m without breaking a sweat, just make sure you have the rssi dBm warning set correctly (based on the packet rate you are using) and the rssi dBm and LQ elements active in OSD. As ever you know how to test it, fly out to 100m, fly in a circle, check your signal numbers, come back. Do it again but go further this time, say 200m. Then 300m and so forth. When your rssi dBm gets with 10 of the failure point, that's your limit. So I run 150Hz packet rate, so my RSSI dBm warning is set to -100 (limit at 150Hz is -112). If I were to reach -90 I would probably call it the limit as I like to be conservative with things, so I have a lot of wiggle room if something goes wrong.

As to your antenna, replace it with a TrueRC or something else with higher gain if you are worried. I would try a Lollipop or Cherry or if you have lots of spare money something from TrueRC. At the same time replace your goggles antennas with good quality antennas, maybe one patch, one omni, or two patch if you are looking for more range.

If you are flying nearby (in your own neighborhood) and not in a very challenging RF environment, then it should be fine. But those single enamel wires are inferior, even if you don't have them hidden by the boards/carbon fiber. I think the manufacturers use it simply to save cost. With the t-dipole you can also locate the antenna further out in the clear and will have better reception.
If you are concerned with the reception, you can go with a lower packet rate like 150hz and your link will be much more robust, or otherwise if you are comfortable soldering you can replace the antenna with a t-dipole.

I wouldn't worry about your enamel wire at the range that thing should flying at. I've got mine mashed under the VTX and even behind two buildings it never goes below 85% LQ.

Just to be specifically clear, it's the ELRS receiver antenna on the quad that I was referring to, and from the replies so far it would seem the short enameled wire is probably a light, cheap and slightly inferior option, but it may still work fine for relatively short range flying (eg 100-300m or so).

My bassline hardware is currently mounted on a mobula8 frame and this seems to cope with my style of outdoor flying fine generally. I'm finding that the HD video feed (@ 200mW) starts to deteriorate long before the ELRS signal strength drops much so I don't have a lot of feel for how much range the ELRS signal has since I don't want to fly blind.

Just saw on my Mob8 analog version, it actually has the ceramic tower antenna which is potentially better than the wire, but probably there are different versions out there. Most likely you will lose video first, but with the wire antenna I've experienced a rare failsafe while still having video (behind two houses less than 200m away). I suspect some strong wifi routers will still wreak havoc, but back then I was running 500hz. Now I run 150hz and also have a higher power tx, so no failsafes since, but I the LQ still drops in that spot.

The enameled wire antenna will actually outperform the ceramic cube antennas in most cases, and the wire antenna or a simple T-dipole should easily outperform your video link in most cases, as long as you pay attention to the antenna nulls.