[greggold]

I also experienced radio signal issues today with my Tx16s, but there was no loss of control. Rather I had more jumps in tx power (TPWR) today than usual. My RM Tx12 tx (set to dynamic power on) has a minimum default of TPWR of 25 mw and has less frequent jumps. I am doing a comparison flying the same model using the Tx16 and Tx12 on alternate flights.

I posed this question several says ago on Discord Help and Support and I got some responses including from an expert V-22. My Discord user name is Gregor. This link may access the full conversation:
https://discord.com/channels/59635002219...2615555074

Title:  Dynamic power range on a Radiomaster Tx16s

Is there a way to adjust the dynamic power range on a Radiomaster Tx16s?
I am using edgetx 2.7.1, ands elrs 3.0.1
Packet rate 100Hz full, telem ratio Std (1:32).
At my noisy flying environment the tx defaults to minimum TPWR 10 mw on startup and model launch, but there are frequent jumps to 25 mw, and occasional ones to 50 or 100 mw.
My RM Tx12 has a minimum default of TPWR of 25 mw and does not have frequent jumps.
Can I adjust the Tx16s dynamic range so there is a minimum of 25 mw?

Some points are:
For aircraft a packet rate of 100 Hz full is recommended with telem ratio of 1:32. V-22 says a telem ratio Std (1:32) is fine, it means "Link stats frames are sent ~2x/second, and 1:32 at 100Hz should give you ~3 telemetry frames per second." This means at lower packet rates you can use  better telemetry ratios (1:32) providing more frequent updates for the tx which means quicker power jumps when required, eg interference causes the receiver signal to noise ratio to fall.

A post by sunjun (screenshot attached) says it is easy to adjust the  minimum default of TPWR of 10mw on the Tx16s to 25 mw. V-22 says jumps are a sign the Tx16s is working properly, and there is no need to worry.

This discussion of dynamic power is useful:

https://www.expresslrs.org/software/dyna...mit-power/

I will add some flight logs in a subsequent post.

Flight signal issues today.

I compare flight logs of a single 3D plane at PRCAC field today, one flight with the RM TX16s tx and the other with a Tx12. Both flights use elrs with dynamic power turned on. Packet rate is 100 Hz and telemetry ratio is set to 1:32.

Both flights are a bit over 5 minutes. Notice that most of the parameters are divided by 2, so a value of Tx power (TPWR) of 50 on the graph means 100 mw. There are jumps from 10 mw to 25, to 50, and several jumps to 100 in the Tx16s flight, more than I have previously experienced. I only had 1 jump in all my Tx12 flights, and none in the Tx12 log shown..

Notice that there are 2 RSS (receiver signal strength values), as I am using a RM ER6 rx which has 2 antennas (it is not a true diversity rx). Throughout both flights the RSS and RQly (receiver quality, also known as valid frame rate and link quality) remain at normal levels. Thus RQly remained at 80 or above, and RSS did not go below -80.

The main feature is how low the receiver signal to noise ratio (RSNR) is in the Tx16S, compared to the Tx12. Check and compare the number of measurements that are under 5 (this means the number of measurements that fall under the 10 gridline). In the Tx12, only one measurement was under 5, compared to a large number in the Tx16s.  However a value as low as 1 is acceptable if you are using a lower packet ratio. The Tx16s had 8 measurements of RSNR of 0 or below 0, and this is a trigger for a power jump.

I have many similar logs that show the above difference between the Tx16s and the Tx12. This supports the idea that its the base value of dynamic power of 10 mw on the Tx16 (compared to 25 on the Tx12) that causes the lower RSNR values on the Tx16. I have not yet decided whether it is a good idea to change the base value of dynamic power on the Tx16s to 25mw, as discussed in the previous post.